eoe sub articles

EoE Sub Articles

All procedures involving animal models have been reviewed by the local institutional animal care committee and the JoVE veterinary review board.
1. Staircase Test (Figure 1)
<ol>
	<li>Acquisition Phase&#8203;
	<ol>
		<li>One day prior to the training familiarize the animals with the pellets used in the Staircase test.
		<ol>
			<li>Optional: To increase the animal&#39;s motivation use a dietary restriction (10-15 g of standard laboratory chow to maintain body weight at 90% of the free feeding level). However, this is not obligatory to achieve a positive training effect. This study was conducted without food restriction.</li>
		</ol>
		</li>
		<li>Prepare a clear plastic glass staircase box (height: 34.5 cm, length: 35.5 cm, width: 12 cm, and narrow compartment 6 cm) by cleaning the box with a 0.1% acetic acid solution. NOTE: The staircase box is a two-compartment box with a raised platform and two stairs in the narrow compartment. The left steps on the stairs in the narrow compartment can be reached only with the left paw, and the right steps only with the right paw. 
		NOTE: &#160;The standard staircase boxes consist of two compartments with a lid. If they are to be used for experiments with rats stimulated via cable, use a high box without a lid.</li>
		<li>Remove the staircase and fill the wells on each step with eight 45 mg pellets.</li>
		<li>Insert the staircase and put eight additional pellets on the heightened platform.</li>
		<li>Place the rat in the transport box.</li>
		<li>Transport the rat from the home cage to the staircase box using the transport box.</li>
		<li>Place the rat in the staircase box (Figure 2).</li>
		<li>After five minutes, remove the animal from the staircase box and put it back into the home cage using the transport box.</li>
		<li>Note how many pellets were eaten from the platform and (eventually) from the right and left staircases.</li>
		<li>Refill the staircase by filling the wells on each step with eight 45 mg pellets.</li>
		<li>Clean the staircase box with a 0.1% acetic acid solution and place the additional pellets on the platform.</li>
		<li>Repeat this procedure (acquisition phase) three days in a row. 
		NOTE: &#160;All experiments described were performed on male Sprague Dawley rats. The duration of the different training modules can differ in rats of different strains, sexes, and vender.</li>
	</ol>
	</li>
	<li>Free Choice Test
	<ol>
		<li>Clean the staircase box with a 0.1% acetic acid solution.</li>
		<li>Remove the staircase and fill the wells on each step with eight 45 mg pellets.</li>
		<li>Place the rat in the transport box.</li>
		<li>Transport the rat from the home cage to the staircase box using the transport box.</li>
		<li>Place the rat in the staircase box.</li>
		<li>After five minutes, remove the animal from the staircase box and put it back into the home cage using the transport box. 
		Note how many pellets were eaten from the right and left staircase.</li>
		<li>NOTE: If the animals still have problems with grasping pellets, add some more on the platform where they can be easily reached.</li>
		<li>Refill the staircase by filling the wells on each step with eight 45 mg pellets.</li>
		<li>Clean the staircase box with a 0.1% acetic acid solution for the next animal.</li>
		<li>Repeat this procedure (free choice phase) three days in a row. 
		NOTE: The presented results were obtained by training conducted without a resting period between modules. Some groups prefer a resting day for consolidation, to support the training process.</li>
	</ol>
	</li>
	<li>Forced Choice Test&#8203;
	<ol>
		<li>Clean the staircase box with a 0.1% acetic acid solution.</li>
		<li>Remove the staircase and fill the wells on each step on the left staircase with eight (first three days of the module) or four (consecutive three days of the module) 45 mg pellets.
		<ol>
			<li>Perform the forced choice test on the side, where the impairment will occur. 
			NOTE: We perform the Parkinson&#39;s lesion on the right hemisphere and therefore train selectively the left paw.</li>
		</ol>
		</li>
		<li>Place the rat in the transport box.</li>
		<li>Transport the rat from the home cage to the staircase box using the transport box.</li>
		<li>Place the rat in the staircase box.</li>
		<li>After five minutes, remove the animal from the staircase box and put it back into the home cage using the transport box.</li>
		<li>Note how many pellets were eaten from the left staircase.</li>
		<li>Refill the staircase by filling the wells on each step with eight or four 45 mg pellets (the number of pellets depends on the training day).</li>
		<li>Clean the staircase box with a 0.1% acetic acid solution for the next animal.</li>
		<li>Repeat this procedure (forced choice phase) six days in a row.</li>
	</ol>
	</li>
	<li>Data Acquisition
	<ol>
		<li>Perform the experiment as described for the forced choice module (four pellets in each well on the left staircase) on two consecutive days. Calculate the success rate (number of pellets eaten) as a mean of the two days.</li>
	</ol>
	</li>
</ol>

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Staircase box witout lid</td>
			<td>Glas Keil, Germany</td>
			<td></td>
			<td>custom made</td>
		</tr>
		<tr>
			<td>Dustless precision pellets, 45 mg</td>
			<td>Bio Serv</td>
			<td>F0021</td>
			<td></td>
		</tr>
	</tbody>
</table>

staircase test for motor function assessment in a hemiparkinsonian rat

Source: Rattka, M, et al., <a href="https://app.jove.com/v/53951">A Novel Approach to Assess Motor Outcome of Deep Brain Stimulation Effects in the Hemiparkinsonian Rat: Staircase and Cylinder Test.</a> J. Vis. Exp. (2016).
This video demonstrates the staircase test to assess motor function in a hemiparkinsonian rat with a right brain lesion. The lesion disrupts dopamine signaling, impairing left paw control, which results in more pellets remaining on the left stairs, indicating motor dysfunction.

<img alt="Figure 1" src="/files/ftp_upload/23195/23195_Figure1.jpg" /> 
Figure 1: Staircase test setup. The staircase box arranged with pellets on the left staircase. (A) side view, (B) view from above.
<img alt="Figure 2" src="/files/ftp_upload/23195/23195_Figure2.jpg" /> 
Figure 2: Staircase test. A hemiparkinsonian rat during staircase test.
(NOTE: crop t...

Staircase Test for Motor Function Assessment in a Hemiparkinsonian Rat

Source: Rattka, M, et al., A Novel Approach to Assess Motor Outcome of Deep Brain Stimulation Effects in the Hemiparkinsonian Rat: Staircase and Cylinder ...

Take a two-compartment staircase box featuring a raised platform and a socket for stairs on both sides.
Arrange the food pellets on the platform and both the stairs and insert it inside the box.
Introduce a rat with hemiparkinsonism, a condition with a lesion in the right hemisphere of the brain.
The rat reaches toward the pellets and uses both paws to grasp the food.
The right hemisphere of the brain regulates the movements on the left side of the body.
The lesion in the right hemisphere damages dopamine-producing neurons, decreasing dopamine or excitatory neurotransmitter levels and reducing signal transmission to the neighboring neurons.
This impairs the motor control of the left paw&#39;s movement.
As a result, the rat prefers using the right paw more than the left one.
Remove the rat and count the remaining pellets on both stairs. More pellets on the left stairs indicate impaired motor function of the rat&#39;s left paw.

staircase-test-for-motor-function-assessment-in-a-hemiparkinsonian-rat

Research

JoVE Encyclopedia of Experiments

Neuroscience

Neuropathology

Neuromuscular Disorders

25 visualizações. Source: Rattka, M, et al., A Novel Approach to Assess Motor Outcome of Deep Brain Stimulation Effects in the Hemiparkinsonian Rat: Staircase and Cylinder Test. J. Vis. Exp. (2016). This video demonstrates the staircase test to assess motor function in a hemiparkinsonian rat with a right brain lesion. The lesion disrupts dopamine signaling, impairing left paw control, which results in more pellets remaining on the left stairs, indicating motor dysfunction. 

Vídeo: Staircase Test for Motor Function Assessment in a Hemiparkinsonian Rat - Conceito

Controlling Parkinson's Disease With Adaptive Deep Brain Stimulation

Adaptive deep brain stimulation (aDBS) has the potential to improve the treatment of Parkinson&#39;s disease by optimizing stimulation in real time according to fluctuating disease and medication state. In the present realization of adaptive DBS we record and stimulate from the DBS electrodes implanted in the subthalamic nucleus of patients with Parkinson&#39;s disease in the early post-operative period. Local field potentials are analogue filtered between 3 and 47 Hz before being passed to a data acquisition unit where they are digitally filtered again around the patient specific beta peak, rectified and smoothed to give an online reading of the beta amplitude. A threshold for beta amplitude is set heuristically, which, if crossed, passes a trigger signal to the stimulator. The stimulator then ramps up stimulation to a pre-determined clinically effective voltage over 250 msec and continues to stimulate until the beta amplitude again falls down below threshold. Stimulation continues in this manner with brief episodes of ramped DBS during periods of heightened beta power.
Clinical efficacy is assessed after a minimum period of stabilization (5 min) through the unblinded and blinded video assessment of motor function using a selection of scores from the Unified Parkinson&#39;s Rating Scale (UPDRS). Recent work has demonstrated a reduction in power consumption with aDBS as well as an improvement in clinical scores compared to conventional DBS. Chronic aDBS could now be trialed in Parkinsonism.

Adaptive deep brain stimulation (aDBS) is effective for Parkinson&#8217;s disease, improving symptoms and reducing power consumption compared to conventional deep brain stimulation (cDBS). In aDBS we track a local field potential biomarker (beta oscillatory amplitude) in real time and use this to control the timing of stimulation.

Controlar a doença de Parkinson com Adaptive Estimulação Cerebral Profunda

Adaptive deep brain stimulation (aDBS) has the potential to improve the treatment of Parkinson&#39;s disease by optimizing stimulation in real time ...

JoVE Journal

Medicina

Deep Brain Stimulation with Simultaneous fMRI in Rodents

In order to visualize the global and downstream neuronal responses to deep brain stimulation (DBS) at various targets, we have developed a protocol for using blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) to image rodents with simultaneous DBS. DBS fMRI presents a number of technical challenges, including accuracy of electrode implantation, MR artifacts created by the electrode, choice of anesthesia and paralytic to minimize any neuronal effects while simultaneously eliminating animal motion, and maintenance of physiological parameters, deviation from which can confound the BOLD signal.&#160;Our laboratory has developed a set of procedures that are capable of overcoming most of these possible issues. For electrical stimulation, a homemade tungsten bipolar microelectrode is used, inserted stereotactically at the stimulation site in the anesthetized subject. In preparation for imaging, rodents are fixed on a plastic headpiece and transferred to the magnet bore. For sedation and paralysis during scanning, a cocktail of dexmedetomidine and pancuronium is continuously infused, along with a minimal dose of isoflurane; this preparation minimizes the BOLD ceiling effect of volatile anesthetics. In this example experiment, stimulation of the subthalamic nucleus (STN) produces BOLD responses which are observed primarily in ipsilateral cortical regions, centered in motor cortex. Simultaneous DBS and fMRI allows the unambiguous modulation of neural circuits dependent on stimulation location and stimulation parameters, and permits observation of neuronal modulations free of regional bias. This technique may be used to explore the downstream effects of modulating neural circuitry at nearly any brain region, with implications for both experimental and clinical DBS.

This protocol describes a standard method for simultaneous functional magnetic resonance imaging and deep brain stimulation in the rodent. The combined use of these experimental tools allows for the exploration of global downstream activity in response to electrical stimulation at virtually any brain target.

Estimulação Cerebral Profunda com fMRI simultâneo em Roedores

In order to visualize the global and downstream neuronal responses to deep brain stimulation (DBS) at various targets, we have developed a protocol for ...

Neurociência

In vivo Positron Emission Tomography to Reveal Activity Patterns Induced by Deep Brain Stimulation in Rats

Deep brain stimulation (DBS) is an invasive neurosurgical technique based on the application of electrical pulses to brain structures involved in the patient&#39;s pathophysiology. Despite the long history of DBS, its mechanism of action and appropriate protocols remain unclear, highlighting the need for research aiming to solve these enigmas. In this sense, evaluating the in vivo effects of DBS using functional imaging techniques represents a powerful strategy to determine the impact of stimulation on brain dynamics. Here, an experimental protocol for preclinical models (Wistar rats), combined with a longitudinal study [18F]-fluorodeoxyclucose positron emission tomography (FDG-PET), to assess the acute consequences of DBS on brain metabolism is described. First, animals underwent stereotactic surgery for bilateral implantation of electrodes into the prefrontal cortex. A post-surgical computerized tomography (CT) scan of each animal was acquired to verify electrode placement. After one week of recovery, a first static FDG-PET of each operated animal without stimulation (D1) was acquired, and two days later (D2), a second FDG-PET was acquired while animals were stimulated. For that, the electrodes were connected to an isolated stimulator after administering FDG to the animals. Thus, animals were stimulated during the FDG uptake period (45 min), recording the acute effects of DBS on brain metabolism. Given the exploratory nature of this study, FDG-PET images were analyzed by a voxel-wise approach based on a paired T-test between D1 and D2 studies. Overall, the combination of DBS and imaging studies allows describing the neuromodulation consequences on neural networks, ultimately helping to unravel the conundrums surrounding DBS.

In vivo Positron Emission Tomography to Reveal Activity Patterns Induced by Deep Brain Stimulation in Rats

We describe a preclinical experimental method to evaluate metabolic neuromodulation induced by acute deep brain stimulation with in vivo FDG-PET. This manuscript includes all experimental steps, from stereotaxic surgery to the application of the stimulation treatment and the acquisition, processing, and analysis of PET images.

In vivo Tomografia por emissão de pósitrons para revelar padrões de atividade induzidos pela estimulação cerebral profunda em ratos

Deep brain stimulation (DBS) is an invasive neurosurgical technique based on the application of electrical pulses to brain structures involved in the ...

Staircase Test for Motor Function Assessment in a Hemiparkinsonian Rat

Transcrição

Staircase Test for Motor Function Assessment in a Hemiparkinsonian Rat

Controlar a doença de Parkinson com Adaptive Estimulação Cerebral Profunda

Estimulação Cerebral Profunda com fMRI simultâneo em Roedores

In vivo Tomografia por emissão de pósitrons para revelar padrões de atividade induzidos pela estimulação cerebral profunda em ratos