Name: a rat model of central fatigue using a modified multiple platform method
Uploaded: 2018-08-14T13:30:00
Description: Watch this Scientific Journal Video about A Rat Model of Central Fatigue Using a Modified Multiple Platform Method at JoVE.com

This work was supported by Natural Science Foundation of Beijing (No.7162124), and Xin-ao Foundation for Beijing University of Chinese Medicine.

All the animals were maintained in accordance with the guidelines by the Chinese legislation on the ethical use and care of laboratory animals.
1. Pre-modeling Preparation
<ol>
	<li>Laboratory preparation
	<ol>
		<li>Run the UV lamp for at least 30 min before the experiment.</li>
		<li>Control the lab temperature at 25 &#177; 3 &#176;C, and relative humidity around 30%.</li>
		<li>Turn on the lab light at 6:00 and turn it off at 18:00 to establish a 12 h/12 h light/dark cycl...

<ol>
	<li>Ishii, A., Tanaka, M., Yamano, E., Watanabe, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+neural+substrates+of+physical+fatigue+sensation+to+evaluate+ourselves:+a+magnetoencephalography+study.">The neural substrates of physical fatigue sensation to evaluate ourselves: a magnetoencephalography study.</a> Neuroscience. 261, 60-67 (2014).</li><li>Dalsgaard, M. K., Secher, N. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Brain+at+Work:+A+Cerebral+Metabolic+Manifestation+of+Central+Fatigue?.">The Brain at Work: A Cerebral Metabolic Manifestation of Central Fatigue?.</a> Journal of Neuroscience Research. 85 (15), 3334-3339 (2007).</li><li>Chaudhuri, A., Behan, P. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fatigue+in+neurological+disorders.">Fatigue in neurological disorders.</a> The Lancet. 363, 978-988 (2004).</li><li>Baston, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Exercise-induced+central+fatigue:+a+review+of+the+literature+with+implications+for+dance+science+research.">Exercise-induced central fatigue: a review of the literature with implications for dance science research.</a> Journal of Dance Medicine &amp; Science. 17 (2), 53-62 (2013).</li><li>Yamashita, M., Yamamoto, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tryptophan+and+Kynurenic+Acid+May+Produce+an+Amplified+Effect+in+Central+Fatigue+Induced+by+Chronic+Sleep+Disorder.">Tryptophan and Kynurenic Acid May Produce an Amplified Effect in Central Fatigue Induced by Chronic Sleep Disorder.</a> International Journal of Tryptophan Research. 7, 9-14 (2014).</li><li>Lee, S. W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+impact+of+duration+of+one+bout+treadmill+exercise+on+cell+proliferation+and+central+fatigue+in+rats.">The impact of duration of one bout treadmill exercise on cell proliferation and central fatigue in rats.</a> Journal of Exercise Rehabilitation. 9 (5), 463-469 (2013).</li><li>Su, k. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rutin,+a+flavonoid+and+principal+component+of+saussurea+involucrata,+attenuates+physical+fatigue+in+a+forced+swimming+mouse+model.">Rutin, a flavonoid and principal component of saussurea involucrata, attenuates physical fatigue in a forced swimming mouse model.</a> International Journal of Medical Sciences. 11 (5), 528-537 (2014).</li><li>Hashemi, F., Laufer, R., Szegi, P., Csomor, V., Kal &#225;sz, H., Tekes, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=HPLC+determination+of+brain+biogenic+amines+following+treatment+with+bispyridinium+aldoxime+K203.">HPLC determination of brain biogenic amines following treatment with bispyridinium aldoxime K203.</a> Acta Physiologica Hungarica. 101 (1), 40-46 (2014).</li><li>Machado, R. B., Hipo'lide, D. C., Benedito-Silva, A. A., Tufik, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sleep+deprivation+induced+by+the+modified+multiple+platform+technique:+quantification+of+sleep+loss+and+recovery.">Sleep deprivation induced by the modified multiple platform technique: quantification of sleep loss and recovery.</a> Brain Research. 1004 (1-2), 45-51 (2004).</li><li>Alzoubi, K. H., Khabour, O. F., Tashtoush, N. H., AI-Azzam, S. I., Mhaidat, N. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+the+Effect+of+Pentoxifylline+on+Sleep-Deprivation+Induced+Memory+Impairment.">Evaluation of the Effect of Pentoxifylline on Sleep-Deprivation Induced Memory Impairment.</a> Hippocampus. 23 (9), 812-819 (2013).</li><li>Pires, G. N., Tufik, S., Andersen, M. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Grooming+analysis+algorithm:+Use+in+the+relationship+between+sleep+deprivation+and+anxiety-like+behavior.">Grooming analysis algorithm: Use in the relationship between sleep deprivation and anxiety-like behavior.</a> Progress in Neuro-Psychopharmacology and Biological Psychiatry. 41, 6-10 (2013).</li><li>Yamashita, M., Yamamoto, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Establishment+of+a+rat+model+of+central+fatigue+induced+by+chronic+sleep+disorder+and+excessive+brain+tryptophan.">Establishment of a rat model of central fatigue induced by chronic sleep disorder and excessive brain tryptophan.</a> Japanese Journal of Cognitive Neuroscience. 15, 67-74 (2013).</li><li>Arai, M., Yamazaki, M., Inoue, K., Fushiki, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effects+of+intracranial+injection+of+transforming+growth+factor-beta+relevant+to+central+fatigue+on+the+waking+electroencephalogram+of+rats+Comparison+with+effects+of+exercise.">Effects of intracranial injection of transforming growth factor-beta relevant to central fatigue on the waking electroencephalogram of rats Comparison with effects of exercise.</a> Progress in Neuro-Psychopharmacology and Biological Psychiatry. 26 (2), 307-312 (2002).</li><li>Han, C. X., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distinct+behavioral+and+brain+changes+after+different+durations+of+the+modified+multiple+platform+method+on+rats:+An+animal+model+of+central+fatigue.">Distinct behavioral and brain changes after different durations of the modified multiple platform method on rats: An animal model of central fatigue.</a> PloS One. 12 (5), e0176850 (2017).</li><li>Tang, X., Yang, L., Sanford, L. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Individual+variation+in+sleep+and+motor+activity+in+rats.">Individual variation in sleep and motor activity in rats.</a> Behavioural Brain Research. 180 (1), 62-68 (2007).</li><li>Stanford, S. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Open+Field+Test:+reinventing+the+wheel.">The Open Field Test: reinventing the wheel.</a> Journal of Psychopharmacology. 21 (2), 134-135 (2007).</li><li>Ahn, S. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Basal+anxiety+during+an+open+field+test+is+correlated+with+individual+differences+in+contextually+conditioned+fear+in+mice.">Basal anxiety during an open field test is correlated with individual differences in contextually conditioned fear in mice.</a> Animal Cells and Systems. 17 (3), 154 (2013).</li><li>Costa, A. A., Morato, S., Roque, A. C., Tin &#243;s, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+computational+model+for+exploratory+activity+of+rats+with+different+anxiety+levels+in+elevated+plus-maze.">A computational model for exploratory activity of rats with different anxiety levels in elevated plus-maze.</a> Journal of Neuroscience Methods. 236, 44-50 (2014).</li><li>Liu, Z., Wu, Y., Liu, T., Li, R., Xie, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Serotonin+regulation+in+a+rat+model+of+exercise-induced+chronic+fatigue.">Serotonin regulation in a rat model of exercise-induced chronic fatigue.</a> Neuroscience. 349, 27-34 (2017).</li><li>Foley, T. E., Fleshner, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Neuroplasticity+of+dopamine+circuits+after+exercise:+implications+for+central+fatigue.">Neuroplasticity of dopamine circuits after exercise: implications for central fatigue.</a> NeuroMolecular Medicine. 10 (2), 67-80 (2008).</li><li>Leite, L. H., Rodrigues, A. G., Soares, D. D., Marubayashi, U., Coimbra, C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Central+fatigue+induced+by+losartan+involves+brain+serotonin+and+dopamine+content.">Central fatigue induced by losartan involves brain serotonin and dopamine content.</a> Medicine &amp; Science in Sports &amp; Exercise. 42 (8), 1469-1476 (2010).</li></ol>

The MMPM is originally designed for sleep deprivation9. Rats are launched into a water tank with platforms fixed on the bottom. Driven by the instinctive fear of water, rats remain standing on the platforms and no sleep occurs. The study shows that different hours of sleep deprivation lead to various changes in rat behavior and mood, including recognition impairment10, negative emotions11, and central fatigue. Some researchers prove that chronic slee...

Fatigue is one of the main factors that threaten human health1. In the past decades, various researches have proved that fatigue is peripherally-triggered but centrally-driven, and always accompanied with emotional and cognitive disorders. Italian physiologist A. Mosso first proposed the word Central Fatigue2. It is generally defined as limited voluntary activity and cognition impairment due to dysfunction of impulse transmission in the central nervous system (CNS)3. Compared with peripheral muscle fatigue, central fatigue emphasizes changes in the CNS, as well as the consequent emotional/behavioral disturbances, including depression, anxiety, cognition impairment, and memory loss. One study shows that many factors can induce central fatigue, among which excessive physical activity and mental stress are quite indispensable4. As for the pathogenesis, theories like the tryptophan-kynurenine pathway hypothesis5 explain changes in certain pathways; however, more in-depth studies are still required&#160;to reveal the central-peripheral correlations of central fatigue.
As the underlying mechanism of central fatigue is still unclear, an effective animal model is quite important for further research. The existing fatigue models are mostly induced by excessive exercise, like treadmills6 and weight-loaded swimming7, with little concern on mental factors. To better simulate the development of central fatigue, our group developed a rat model with the MMPM. During the modeling process, rats remain standing on the narrow platforms in the Multiple Platform box for long hours including part of the sleep time. Different from excessive exercise models, the MMPM model uses partial sleep deprivation as a mental factor in consideration of the complex pathogenesis of central fatigue.
For model evaluation, we use the OFT and EPM tests to determine anxiety mood and voluntary activity. The ES test is performed to measure the peripheral muscle performance. In addition, we take the rat&#39;s brain and detect dopamine (DA)/serotonin (5-HT) content in both hypothalamuses to observe the central neurotransmitter differences.
The protocol presented below is designed to model central fatigue induced by repeated physical activity and lack of sleep, mimicking a common condition in human life. However, by adjusting the model duration, it can be used in many other fields, like in sleep observation and stress studies. In future research, we hope that this model will help discover more CNS changes and their connection with the peripheral system, to reveal the pathogenesis mechanism of central fatigue.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>multiple platform sleep deprivation water tank</td>
			<td>Customization,it is provided by the neuroimmunological laboratory of Beijing University of Chinese Medicine</td>
			<td></td>
			<td>110cm x 60cm x 40cm. There are 15 plastic small platforms at the bottom. The small platform is 6.5cm in diameter and 8cm high</td>
		</tr>
		<tr>
			<td>Wistar rats</td>
			<td>Beijing Weitong Lihua Experimental Animal Technology Company</td>
			<td>license number SYXK (Beijing) 2016-0011</td>
			<td>Use 32 Wistar healthy male rats ,8 week old (200-210 g)</td>
		</tr>
		<tr>
			<td>Agilent 1100LC high performance liquid chromatograph&#160;</td>
			<td>Agilent</td>
			<td>&#160;G1379A, G1311A, G1313A , G1316A&#160;</td>
			<td>&#160;G1379A, G1311A type chromatographic pump, G1313A automatic sampler, G1316A column temperature box</td>
		</tr>
		<tr>
			<td>DECADE II SDC electrochemical detector</td>
			<td>Dutch ANTEC company</td>
			<td></td>
			<td>glassy carbon electrode, Ag/AgCl reference electrode, workstations (Clarity CHS)</td>
		</tr>
		<tr>
			<td>Biofuge Stratos high-speed refrigeration centrifuge</td>
			<td>HERAEUS</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>VCX130 ultrasonic fracturing instrument</td>
			<td>SONICS</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>ACS-ZEAS electronic scale</td>
			<td>Phos technology development, Beijing.</td>
			<td></td>
			<td>The weight of the weighing rats can be accurate to 0.1g.</td>
		</tr>
		<tr>
			<td>Open Field Box</td>
			<td>Customization,it is provided by the neuroimmunological laboratory of Beijing University of Chinese Medicine</td>
			<td></td>
			<td>wooden box of open field&#160; 100 cm by 100 cm x 40 cm, inside wall and bottom as the gray.The bottom is divided into 25 equal area squares, each of which is 20cm x 20cm, and the 16 grids along the outer wall are the external ones, and the other 9 grids are central.The camera is mounted above the median.</td>
		</tr>
		<tr>
			<td>Elevated Plus-maze</td>
			<td>Beijing zhongshi dechuang technology development co. LTD.</td>
			<td></td>
			<td>The open arms and close&#160; arms of the cross are composed of 30cm x 5cm x 15cm, and the central area is 5cm x 5cm, with a camera mounted above the center and 45cm high.</td>
		</tr>
		<tr>
			<td>rat swimming bucket.</td>
			<td>Zhenhua biological instrument equipment co., LTD. Anhui,China.</td>
			<td></td>
			<td>The volume of plastic drum is 70cm x 30cm x 110cm, which is used for swimming in rats.</td>
		</tr>
		<tr>
			<td>Thermometer</td>
			<td>Shiya instrument co., LTD., changzhou,China.</td>
			<td></td>
			<td>Control water temperature</td>
		</tr>
		<tr>
			<td>Small water pump</td>
			<td>Xincheng technology co., LTD., chengdu,China.</td>
			<td></td>
			<td>Used for water tank and swimming behavior.</td>
		</tr>
		<tr>
			<td>Ethovition3.0 behavioral software.</td>
			<td>Nuldus,Netherlands</td>
			<td></td>
			<td>Measurement analysis of rat behavior videos.</td>
		</tr>
	</tbody>
</table>

a rat model of central fatigue using a modified multiple platform method

In this article, we introduced a rat model of central fatigue using the modified multiple platform method (MMPM). The Multiple Platform box was designed as a water tank with narrow platforms on the bottom. The model rats were put into the tank and stood on the platforms for 14 h (18:00 - 8:00) per day for a consecutive 21 days, with a blank control group set for contrast. At the end of modeling, rats in the model group showed an obvious fatigued appearance. To assess the model, we performed several behavioral tests, including the open field test (OFT), the elevated plus maze (EPM) test, and the exhaustive swimming (ES) test. The results showed that anxiety, spatial cognition impairment, poor muscle performance, and declined voluntary activity presented in model rats confirm the diagnosis of&#160;central fatigue. Changes of the central neurotransmitters also verified the result. In conclusion, the model successfully simulated central fatigue, and future study with the model may help reveal the pathological mechanism of the disease.

We describe a rat model of central fatigue using MMPM. 24 Wistar rats are randomly divided into the control group and the model group, with 12 rats in each group. The model apparatus is designed as a water tank with narrow platforms on the bottom (Figure 1). Model Rats stand on the platforms for 14 h per day, including partial sleep time, for 21 days (Figure 2).
Behavio...

Watch this Scientific Journal Video about A Rat Model of Central Fatigue Using a Modified Multiple Platform Method at JoVE.com

A Rat Model of Central Fatigue Using a Modified Multiple Platform Method

Here, we present a protocol to introduce a rat model of central fatigue using the modified multiple platform method (MMPM).

In this article, we introduced a rat model of central fatigue using the modified multiple platform method (MMPM). The Multiple Platform box was designed ...

This method can help answer key questions in the model construction of central fatigue. For example, how to produce fatigue from both physical and psychological aspects and how to assess it. The main advantage of this technique is to compound mental factors with modified multiple platform method to better simulate the onset of central fatigue.We first came up with the idea when we noticed the close association between intermittent sleep deprivation and central fatigue. We tried different hours and days of deprivation to induce central fatigue, and finally, found that 14 hours over 21 days was the right pattern. The model shows good validity in central fatigue, and it can be used in future studies to help review the underlying mechanism of the disease.Begin by constructing an opaque plastic tank without a cover. Fix 15 circular platforms on the bottom of the tank, which orderly distribute in three rows and five columns. Leave enough space between each platform, roughly 13 centimeters between rows and 10 centimeters between columns.Install a faucet in the water outlet on the lateral side of the tank. Finally, make an iron-wire netting cover for the tank, with a food box hanging on it. Begin by numbering the rats'tail roots with a marker.Weigh the rats, excluding the extremely light or heavy ones, and divide the rest randomly into the model and control groups. Put the rats gently into the clean cages, and allow them to acclimate to the lab for at least three days. Provide sufficient water and food supply.Begin by placing the tank on a flat service, then fill with seven centimeters of warm water, approximately one centimeter below the platform flat. Then put one day's worth of fodder and water into the food box, and hang it on the cover. Next, take the model group of rats out of the cage by the tail, and put them gently into the tank.Launch all the rats in the water instead of the platforms to motivate their fear of water. Make sure that every rat gets a platform to stand on, while rats of the control group stay in their original cages with sufficient food and water. Next, cover the tank and monitor the rats.After 14 hours, take the model rats out of the tank, and dry their hair with a dryer. Remark the rats'tails if it fades. Then, return the rat to the original cage with food and water.Finally, flush out the tank and open the faucet to out-flow the sewage. Then, sterilize the tank with a 75%ethanol spray. Open-field test results indicate that, compared with the control group, there is a significant decrease in both rearing movement and average velocity of voluntary activity in model rats.The elevated-plus maze test shows that 21 days of modeling decreased both entries and duration in the open arm significantly compared to the control group, while there was an increase in those in the close arm. The exhaustive swimming test indicated that the swimming duration of the model group is significantly shorter than the control group. Lastly, these results indicate that dopamine in the hypothalamus, as well as the ratio of dopamine to serotonin, significantly decreases in the model group compared to the control group, while serotonin content increases significantly.After watching this video, you should have a good understanding of how to build a multiple platform tank and apply it in your central fatigue model. This is a non-invasive model, which is easy to master. While trying this model, it is critical to keep an eye on the rest, as they are quite aggressive in the first two weeks, and the injury may occur.Though this model aims to provide insight into central fatigue, it can also be applied to other diseases by compounding factors or adjusting model durations, such as navigation fatigue and depression.

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Research

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Neuroscience

Optic Nerve Transection: A Model of Adult Neuron Apoptosis in the Central Nervous System

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. 
The optic nerve can be accessed within the orbit of the eye and completely transected (axotomized), cutting the axons of the entire RGC population. Optic nerve 
transection is a reproducible model of apoptotic neuronal cell death in the adult CNS 1-4. This model is particularly attractive because the vitreous
 chamber of the eye acts as a capsule for drug delivery to the retina, permitting experimental manipulations via intraocular injections. The diffusion of chemicals 
through the vitreous fluid ensures that they act upon the entire RGC population. Moreover, RGCs can be selectively transfected by applying short interfering RNAs 
(siRNAs), plasmids, or viral vectors to the cut end of the optic nerve 5-7 or injecting vectors into their target, the superior colliculus 8. 
This allows researchers to study apoptotic mechanisms in the desired neuronal population without confounding effects on other bystander neurons or surrounding glia. 
An additional benefit is the ease and accuracy with which cell survival can be quantified after injury. The retina is a flat, layered tissue and RGCs are localized in 
the innermost layer, the ganglion cell layer. The survival of RGCs can be tracked over time by applying a fluorescent tracer (3% Fluorogold) to the cut end of the 
optic nerve at the time of axotomy, or by injecting the tracer into the superior colliculus (RGC target) one week prior to axotomy. The tracer is retrogradely transported, labeling 
the entire RGC population. Because the ganglion cell layer is a monolayer (one cell thick), RGC densities can be quantified in flat-mounted tissue, without the need 
for stereology. Optic nerve transection leads to the apoptotic death of 90% of injured RGCs within 14 days postaxotomy 9-11. RGC apoptosis has a 
characteristic time-course whereby cell death is delayed 3-4 days postaxotomy, after which the cells rapidly degenerate. This provides a time window for 
experimental manipulations directed against pathways involved in apoptosis.

Optic Nerve transection is a widely used model of adult CNS injury. Ninety percent of retinal ganglion cells (RGCs) whose axons are completely transected (axotomy) die within 14 days after axotomy. This model is easily amenable to experimental manipulations and highly reproducible.

Retinal ganglion cells (RGCs) are CNS neurons that output visual information from the retina to the brain, via the optic nerve. 
The optic nerve can be ...

A Novel Method of Drug Administration to Multiple Zebrafish (Danio rerio) and the Quantification of Withdrawal

Anxiety testing in zebrafish is often studied in combination with the application of pharmacological substances. In these studies, fish are routinely netted and transported between home aquaria and dosing tanks. In order to enhance the ease of compound administration, a novel method for transferring fish between tanks for drug administration was developed. Inserts that are designed for spawning were used to transfer groups of fish into the drug solution, allowing accurate dosing of all fish in the group. This increases the precision and efficiency of dosing, which becomes very important in long schedules of repeated drug administration. We implemented this procedure for use in a study examining the behavior of zebrafish in the light/dark test after administering ethanol with differing 21 day schedules. In fish exposed to daily-moderate amounts of alcohol there was a significant difference in location preference after 2 days of withdrawal when compared to the control group. However, a significant difference in location preference in a group exposed to weekly-binge administration was not observed. 
This protocol can be generalized for use with all types of compounds that are water-soluble and may be used in any situation when the behavior of fish during or after long schedules of drug administration is being examined. The light/dark test is also a valuable method of assessing withdrawal-induced changes in anxiety.

A Novel Method of Drug Administration to Multiple Zebrafish Danio rerio and the Quantification of Withdrawal

A novel method for reducing variability when exposing fish to drugs is explained. Fish exposed to various patterns of ethanol exposure were found to have altered anxiety levels during withdrawal in a light/dark scototaxic assay.

Anxiety testing in zebrafish is often studied in combination with the application of pharmacological substances. In these studies, fish are routinely ...

Regioselective Biolistic Targeting in Organotypic Brain Slices Using a Modified Gene Gun

Transfection of DNA has been invaluable for biological sciences and with recent advances to organotypic brain slice preparations, the effect of various heterologous genes could thus be investigated easily while maintaining many aspects of in vivo biology. There has been increasing interest to transfect terminally differentiated neurons for which conventional transfection methods have been fraught with difficulties such as low yields and significant losses in viability. Biolistic transfection can circumvent many of these difficulties yet only recently has this technique been modified so that it is amenable for use in mammalian tissues.
New modifications to the accelerator chamber have enhanced the gene gun&#39;s firing accuracy and increased its depths of penetration while also allowing the use of lower gas pressure (50 psi) without loss of transfection efficiency as well as permitting a focused regioselective spread of the particles to within 3 mm. In addition, this technique is straight forward and faster to perform than tedious microinjections. Both transient and stable expression are possible with nanoparticle bombardment where episomal expression can be detected within 24 hr and the cell survival was shown to be better than, or at least equal to, conventional methods. This technique has however one crucial advantage: it permits the transfection to be localized within a single restrained radius thus enabling the user to anatomically isolate the heterologous gene&#39;s effects. Here we present an in-depth protocol to prepare viable adult organotypic slices and submit them to regioselective transfection using an improved gene gun.

Recent improvements in organotypic brain slice preparations have permitted their exploitation for biotechnological applications. Organotypic slices maintain local structural characteristics of in vivo biology, including functional synaptic connections. Here we present a regioselective biolistic delivery method to label and genetically manipulate these slices.

Transfection of DNA has been invaluable for biological sciences and with recent advances to organotypic brain slice preparations, the effect of various ...

A Method of Nodose Ganglia Injection in Sprague-Dawley Rat

Afferent signaling via the vagus nerve transmits important general visceral information to the central nervous system from many diverse receptors located in the organs of the abdomen and thorax. The vagus nerve communicates information from stimuli such as heart rate, blood pressure, bronchopulmonary irritation, and gastrointestinal distension to the nucleus of solitary tract of the medulla. The cell bodies of the vagus nerve are located in the nodose and petrosal ganglia, of which the majority are located in the former. The nodose ganglia contain a wealth of receptors for amino acids, monoamines, neuropeptides, and other neurochemicals that can modify afferent vagus nerve activity. Modifying vagal afferents through systemic peripheral drug treatments targeted at the receptors on nodose ganglia has the potential of treating diseases such as sleep apnea, gastroesophageal reflux disease, or chronic cough. The protocol here describes a method of injection neurochemicals directly into the nodose ganglion. Injecting neurochemicals directly into the nodose ganglia allows study of effects solely on cell bodies that modulate afferent nerve activity, and prevents the complication of involving the central nervous system as seen in systemic neurochemical treatment. Using readily available and inexpensive equipment, intranodose ganglia injections are easily done in anesthetized Sprague-Dawley rats.

Afferent vagal signaling transmits important information to central nervous system from receptors located in organs of the abdomen and thorax. The nodose ganglia of vagus nerves contain many types of receptors that modulate vagal activity. This protocol describes a method of local injections of neurochemicals into the nodose ganglia.

Afferent signaling via the vagus nerve transmits important general visceral information to the central nervous system from many diverse receptors located ...

Dynamic Quantitative Sensory Testing to Characterize Central Pain Processing

Central facilitation and modulation of incoming nociceptive signals play an important role in the perception of pain. Disruption in central pain processing is present in many chronic pain conditions and can influence responses to specific therapies. Thus, the ability to precisely describe the state of central pain processing has profound clinical significance in both prognosis and prediction. Because it is not practical to record neuronal firings directly in the human spinal cord, surrogate behavior tests become an important tool to assess the state of central pain processing. Dynamic QST is one such test, and can probe both the ascending facilitation and descending modulation of incoming nociceptive signals via TS and CPM, respectively. Due to the large between-individual variability in the sensitivity to noxious signals, standardized TS and CPM tests may not yield any meaningful data in up to 50% of the population due to floor or ceiling effects. We present methodologies to individualize TS and CPM so we can capture these measures in a broader range of individuals than previously possible. We have used these methods successfully in several studies at the lab, and data from one ongoing study will be presented to demonstrate feasibility and potential applications of the methods.

By assessing pain in response to repetitive or different types of standardized stimuli, dynamic quantitative sensory testing (QST) can reveal changes in the central processing of pain. We present methods to optimize and individualize two dynamic QST measures: temporal summation (TS) and conditioned pain modulation (CPM).

Central facilitation and modulation of incoming nociceptive signals play an important role in the perception of pain. Disruption in central pain ...

Measuring Progressive Neurological Disability in a Mouse Model of Multiple Sclerosis

After intracerebral infection with the Theiler's Murine Encephalomyelitis Virus (TMEV), susceptible SJL mice develop a chronic-progressive demyelinating disease, with clinical features similar to the progressive forms of multiple sclerosis (MS). The mice show progressive disability with loss of motor and sensory functions, which can be assessed with multiple apparatuses and protocols. Among them, the Rotarod performance test is a very common behavioral test, its advantage being that it provides objective measurements, but it is often used assuming that it is straightforward and simple. In contrast to visual scoring systems used in some models of MS, which are highly subjective, the Rotarod test generates an objective, measurable, continuous variable (i.e., length of time), allowing almost perfect inter-rater concordances. However, inter-laboratory reliability is only achieved if the various testing parameters are replicated. In this manuscript, recommendations of specific testing parameters, such as size, speed, and acceleration of the rod; amount of training given to the animals; and data processing, are presented for the Rotarod test.

An optimized testing protocol is presented in this paper for the Rotarod performance test, used for measuring progressive neurological disability in TMEV-infected mice.

After intracerebral infection with the Theiler's Murine Encephalomyelitis Virus (TMEV), susceptible SJL mice develop a chronic-progressive demyelinating ...

A Volumetric Method for Quantification of Cerebral Vasospasm in a Murine Model of Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is a subtype of hemorrhagic stroke. Cerebral vasospasm that occurs in the aftermath of the bleeding is an important factor determining patient outcome and is therefore frequently taken as a study endpoint. However, in small animal studies on SAH, quantification of cerebral vasospasm is a major challenge. Here, an ex vivo method is presented that allows quantification of volumes of entire vessel segments, which can be used as an objective measure to quantify cerebral vasospasm. In a first step, endovascular casting of the cerebral vasculature is performed using a radiopaque casting agent. Then, cross-sectional imaging data are acquired by micro computed tomography. The final step involves 3-dimensional reconstruction of the virtual vascular tree, followed by an algorithm to calculate center lines and volumes of the selected vessel segments. The method resulted in a highly accurate virtual reconstruction of the cerebrovascular tree shown by a diameter-based comparison of anatomical samples with their virtual reconstructions. Compared with vessel diameters alone, the vessel volumes highlight the differences between vasospastic and non-vasospastic vessels shown in a series of SAH and sham-operated mice.

The goal of this article is to present a method that allows a 3-dimensional reconstruction of the cerebrovascular tree in mice after micro computed tomography and determination of volumes of entire vessel segments that can be used to quantify cerebral vasospasm in murine models of subarachnoid hemorrhage.

Subarachnoid hemorrhage (SAH) is a subtype of hemorrhagic stroke. Cerebral vasospasm that occurs in the aftermath of the bleeding is an important factor ...

Direct Injection of a Lentiviral Vector Highlights Multiple Motor Pathways in the Rat Spinal Cord

Introducing proteins of interest into cells in the nervous system is challenging due to innate biological barriers that limit access to most molecules. Injection directly into spinal cord tissue bypasses these barriers, providing access to cell bodies or synapses where molecules can be incorporated. Combining viral vector technology with this method allows for introduction of target genes into nervous tissue for the purpose of gene therapy or tract tracing. Here a virus engineered for highly efficient retrograde transport (HiRet) is introduced at the synapses of propriospinal interneurons (PNs) to encourage specific transport to neurons in the spinal cord and brainstem nuclei. Targeting PNs takes advantage of the numerous connections they receive from motor pathways such as the rubrospinal and reticulospinal tracts, as well as their interconnection with each other throughout spinal cord segments. Representative tracing using the HiRet vector with constitutively active green fluorescent protein (GFP) shows high fidelity details of cell bodies, axons and dendritic arbors in thoracic PNs and in reticulospinal neurons in the pontine reticular formation. HiRet incorporates well into brainstem pathways and PNs but shows age dependent integration into corticospinal tract neurons. In summary, spinal cord injection using viral vectors is a suitable method for introduction of proteins of interest into neurons of targeted tracts.

This protocol demonstrates injection of a retrogradely transportable viral vector into rat spinal cord tissue. The vector is taken up at the synapse and transported to the cell body of target neurons. This model is suitable for retrograde tracing of important spinal pathways or targeting cells for gene therapy applications.

Introducing proteins of interest into cells in the nervous system is challenging due to innate biological barriers that limit access to most molecules. ...

Dissection and Isolation of Murine Glia from Multiple Central Nervous System Regions

The methods presented here demonstrate laboratory procedures for the dissection of four different regions of the central nervous system (CNS) from murine neonates for the isolation of glial subpopulations. The purpose of the procedure is to dissociate microglia, oligodendrocyte progenitor cells (OPCs), and astrocytes from cortical, cerebellar, brainstem, and spinal cord tissue to facilitate further in vitro analysis. The CNS region isolation procedures allow for the determination of regional heterogeneity among glia in multiple cell culture systems. Rapid CNS region isolation is performed, followed by the mechanical removal of meninges to prevent meningeal cell contamination of glia. This protocol combines gentle tissue dissociation and plating on a specified matrix designed to preserve cell integrity and adherence. Isolating mixed glia from multiple CNS regions provides a comprehensive analysis of potentially heterogenous glia while maximizing the use of individual experimental animals. Additionally, following dissociation of regional tissue, mixed glia are further divided into multiple cell types including microglia, OPCs, and astrocytes for use in either single cell type, cell culture plate inserts, or co-culture systems. Overall, the demonstrated techniques provide a comprehensive protocol of broad applicability for careful dissection of four individual CNS regions from murine neonates and includes methods for the isolation of three individual glia cell types to examine regional heterogeneity in any number of in vitro cell culture systems or assays.

Here we present a protocol for in vitro isolation of multiple glial cell populations from a mouse CNS. This method allows for the segregation of regional microglia, oligodendrocyte precursor cells, and astrocytes to study the phenotypes of each in a variety of culture systems.

The methods presented here demonstrate laboratory procedures for the dissection of four different regions of the central nervous system (CNS) from murine ...

A Hydrophobic Tissue Clearing Method for Rat Brain Tissue

Hydrophobic tissue clearing methods are easily adjustable, fast, and low-cost procedures that allows for the study of a molecule of interest in unaltered tissue samples. Traditional immunolabeling procedures require cutting the sample into thin sections, which restricts the ability to label and examine intact structures. However, if brain tissue can remain intact during processing, structures and circuits can remain intact for the analysis. Previously established clearing methods take significant time to completely clear the tissue, and the harsh chemicals can often damage sensitive antibodies. The iDISCO method quickly and completely clears tissue, is compatible with many antibodies, and requires no special lab equipment. This technique was initially validated for the use in mice tissue, but the current protocol adapts this method to image hemispheres of control and transgenic rat brains. In addition to this, the present protocol also makes several adjustments to preexisting protocol to provide clearer images with less background staining. Antibodies for Iba-1 and tyrosine hydroxylase were validated in the HIV-1 transgenic rat and in F344/N control rats using the present hydrophobic tissue clearing method. The brain is an interwoven network, where structures work together more often than separately of one another. Analyzing the brain as a whole system as opposed to a combination of individual pieces is the greatest benefit of this whole brain clearing method.

Here we present a hydrophobic tissue clearing method that allows for the viewing of target molecules as part of intact brain structures. This technique has now been validated for F344/N control and HIV-1 transgenic rats of both sexes.

Hydrophobic tissue clearing methods are easily adjustable, fast, and low-cost procedures that allows for the study of a molecule of interest in unaltered ...