אנו מודים לד&quot;ר Sanika Chirwa לסקירה ביקורתית של כתב היד הזה. עבודה זו נתמכה על ידי המכון הלאומי לבריאות (DA026947, DA021471, וNS071122).

1. ציוד ואספקה <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> הר כלוב פאראדיי בחלק העליון של טבלת הרטט אנטי (TMI) כדי להקטין את רעש הרקע. </li><li style=";text-align:right;direction:rtl"> המערכת בו זמנית תיקון מהדק amperometry ההקלטה דורשת מיקרוסקופ הפוך עם אופטיקה DIC מצוין ועדשת מרחק עבודה ארוכה. חבר את המיקרוסקופ מגדלור לסוללה של מכונית. מקור אור זה DC עבור המערכת יהיה עוד יותר להקטין את הרעש החשמלי. </li><li style=";text-align:right;direction:rtl"> micromanipulators ההידראולי (Siskiyou) רעש ירידה נוסף. בתצורה שלנו, אנו משתמשים בידי מניפולטור זכות להקלטת התא כולו, ונתן לשמאל amperometry. </li></ol> 2. הכן אלקטרודות להקלטה <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> משוך אלקטרודות תיקון באמצעות pipettes קוורץ על חולץ P-2000 (סאטר). המשיכה שלנו נמשכת כ 5 שניות, עם שני מחזורי חום. זמן חום זה הביא התנגדות עקבית (3-4 MΩ) בpipettes תיקון התאים השלמים שלנו. </li><li style=";text-align:right;direction:rtl"> מלא את האלקטרודה עםפתרון פיפטה המכיל דופמין 2 המ&quot;מ ולהתקינה על מניפולטור הנכון. עטוף את המכל מחזיק פתרון פיפטה מכיל DA עם רדיד אלומיניום. שמור על קרח. דופמין הוא oxidizable. שמירה על הפתרון בקרח, מוגן מפני אור תקטין את שיעור החמצון של דופמין. </li><li style=";text-align:right;direction:rtl"> בעדינות להסיר את האלקטרודה ProCFE (דגן) רעש נמוכה סיבי פחם amperometric מתיבת האחסון, למלא עם כספית, הר על מתאם amperometric (כמתואר באיור 1), ולאחר מכן לעלות על maniupulator הנכון. הגן על קצה סיב פחמן מניזק על ידי מחזיק בקצה המרוחק של סיבי הפחם. בדוק את האלקטרודה עם מיקרוסקופ מעבדה על מנת להבטיח את הקצה הוא נקי ושלם. </li><li style=";text-align:right;direction:rtl"> בדוק את התקינות של האלקטרודה amperometric ידי לשים את האלקטרודה בצלחת פטרי תחתית כוס המכילה את הפתרון חיצוני. הקלט נוכחי בסיסית בהיעדר דופמין. הוסף 10 μl של פתרון DA 1mm למנה. מחדש האלקטרודה amperometric טובמייתרי גידול בזרם החמצונים. חזור על שלב זה בהתחלה ובסופו של כל ניסוי כדי לוודא את האלקטרודה amperometric עובדת כראוי. </li></ol> 3. הכן את התרבות העצבית הראשונית של נוירונים או תאי דופמין הונדסו טרנספורטר דופאמין בצלחות פטרי תחתית זכוכית <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> לשטוף בעדינות את התאים או נוירונים הדופמין שלוש פעמים עם פתרון חיצוני חם. </li><li style=";text-align:right;direction:rtl"> הר צלחת פטר תחתית הזכוכית על במת מיקרוסקופ. </li></ol> 4. דמיינו תא ולבצע את הניסוי <ol style=";text-align:right;direction:rtl"><li style=";text-align:right;direction:rtl"> מצא את נקודת המיקוד הנכונה בבירור לדמיין את התאים. הנח לחץ חיובי על האלקטרודה התיקון. ואז, בעדינות להביא את שתי אלקטרודות לתוך הפתרון, וקרוב לתא. </li><li style=";text-align:right;direction:rtl"> מקם את האלקטרודה amperometric ליד התא (בצד שמאל), והאלקטרודה התיקון בצד ימין. </li><li style=";text-align:right;direction:rtl"> להשיג חותם gigaohm בתא עם אלקטרודה התיקון. קרע החותם עם יניקהלהשיג תצורת תא כולו. </li><li style=";text-align:right;direction:rtl"> אפשר 5-8 דקות לדיאליזה של פתרון פנימי המכיל דופמין לתא. </li><li style=";text-align:right;direction:rtl"> השתמש צעד מתח רצוי או פרוטוקול רמפה. במקביל תרכשו נתונים משני פיפטה התיקון והאלקטרודה amperometric למדוד זרמי תא שלמים ולהפוך הובלה של דופאמין דרך טרנספורטר דופאמין בעוד פוטנציאל הקרום נשלט באמצעות פיפטה התיקון. </li></ol>

<ol>
	<li>Michael, A. C., Ikeda, M., Justice, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanisms+contributing+to+the+recovery+of+striatal+releasable+dopamine+following+MFB+stimulation.">Mechanisms contributing to the recovery of striatal releasable dopamine following MFB stimulation.</a> Brain Res. 421, 325-335 (1987).</li><li>Gonon, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Prolonged+and+extrasynaptic+excitatory+action+of+dopamine+mediated+by+D1+receptors+in+the+rat+striatum+in+vivo.">Prolonged and extrasynaptic excitatory action of dopamine mediated by D1 receptors in the rat striatum in vivo.</a> J. Neurosci. 17, 5972-5978 (1997).</li><li>Sulzer, D., Pothos, E. N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regulation+of+quantal+size+by+presynaptic+mechanisms.">Regulation of quantal size by presynaptic mechanisms.</a> Rev. Neurosci. 11, 159-212 (2000).</li><li>Napolitano, A., Cesura, A. M., Da Prada, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+monoamine+oxidase+and+catechol+O-methyltransferase+in+dopaminergic+neurotransmission.">The role of monoamine oxidase and catechol O-methyltransferase in dopaminergic neurotransmission.</a> J. Neural. Transm. Suppl. 45, 35-45 (1995).</li><li>Sulzer, D., Maidment, N. T., Rayport, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amphetamine+and+other+weak+bases+act+to+promote+reverse+transport+of+dopamine+in+ventral+midbrain+neurons.">Amphetamine and other weak bases act to promote reverse transport of dopamine in ventral midbrain neurons.</a> J. Neurochem. 60, 527-535 (1993).</li><li>Salahpour, A., 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=Increased+amphetamine-induced+hyperactivity+and+reward+in+mice+overexpressing+the+dopamine+transporter.">Increased amphetamine-induced hyperactivity and reward in mice overexpressing the dopamine transporter.</a> Proc. Natl. Acad. Sci. U.S.A. 105, 4405-4410 (2008).</li><li>Khoshbouei, H., Wang, H., Lechleiter, J. D., Javitch, J. A., Galli, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amphetamine-induced+dopamine+efflux.+A+voltage-sensitive+and+intracellular+Na+-dependent+mechanism.">Amphetamine-induced dopamine efflux. A voltage-sensitive and intracellular Na+-dependent mechanism.</a> J. Biol. Chem. 278, 12070-12077 (2003).</li><li>Goodwin, J. S., 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=Amphetamine+and+methamphetamine+differentially+affect+dopamine+transporters+in+vitro+and+in.">Amphetamine and methamphetamine differentially affect dopamine transporters in vitro and in.</a> , 284-2978 (2009).</li><li>Kahlig, K. M., 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=Amphetamine+induces+dopamine+efflux+through+a+dopamine+transporter+channel.">Amphetamine induces dopamine efflux through a dopamine transporter channel.</a> Proc. Natl. Acad. Sci. U.S.A. 102, 3495-3500 (2005).</li><li>Swant, J., Chirwa, S., Stanwood, G., Khoshbouei, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methamphetamine+reduces+LTP+and+increases+baseline+synaptic+transmission+in+the+CA1+region+of+mouse+hippocampus.">Methamphetamine reduces LTP and increases baseline synaptic transmission in the CA1 region of mouse hippocampus.</a> PLoS One. 5, e11382 (2010).</li><li>Gnegy, M. E., 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=Intracellular+Ca2++regulates+amphetamine-induced+dopamine+efflux+and+currents+mediated+by+the+human+dopamine+transporter.">Intracellular Ca2+ regulates amphetamine-induced dopamine efflux and currents mediated by the human dopamine transporter.</a> Mol. Pharmacol. 66, 137-143 (2004).</li></ol>

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מתח מהדק וamperometry סימולטני מציעים את היתרונות הבאים. כל סוגי התאים נגישים וניתן להשתמש בו להקלטה. זיהוי של תאים או נוירונים בי את ההקלטות נעשות הוא פשוט וברור. בפרט, אם התא מסומן fluorescently ידי הוספת תג ניאון לחלבון של עניין הנסיין יכול לבחור בקלות לתא המטרה או תא העצב. התצ?...

<table border="1" style=";text-align:right;direction:rtl"><tbody><tr><td></td><td></td><td></td><td> ציוד </td></tr><tr><td> נגד רעידות שולחן w / פאראדיי כלוב </td><td> טכנית ייצור חברה </td><td> 63-500 סדרה </td><td> אנו משתמשים במודל 63-543 </td></tr><tr><td> הפוך מיקרוסקופ ניקון TE-2000 </td><td> ניקון </td><td> הופסק </td><td> עכשיו אקליפס Ti </td></tr><tr><td> שני מגברי רעש נמוכים axopatch 200 מיליארדים </td><td> התקנים מולקולריים </td><td></td><td> 800-635-5577 </td></tr><tr><td> 203 headstage 1-CV BU </td><td> התקנים מולקולריים </td><td></td><td> 800-635-5578 </td></tr><tr><td> 1-HL-U בעל פיפטה </td><td> התקנים מולקולריים </td><td></td><td> 800-635-5579 </td></tr><tr><td> Digidata 1440A / D ממיר </td><td> התקנים מולקולריים </td><td></td><td> 800-635-5580 </td></tr><tr><td> שני Siskyou המניפולטורים, עזבוונתן זכות </td><td> Siskiyou </td><td> MX6600R MX6600L </td><td> 877-313-6418 </td></tr><tr><td> ליזר פיפטה חולץ </td><td> סאטר מכשירים </td><td> P-2000 </td><td> 888-883-0128 </td></tr><tr><td> האלקטרודה רעש נמוכה סיבי פחם amperometric </td><td> ProCFE </td><td></td><td> <a href="http://www.dagan.com" target="_blank">www.dagan.com</a> </td></tr><tr><td> רעש הנמוכה קוורץ פיפטה </td><td> סאטר מכשירים </td><td> QF100-70-7.5 </td><td> 888-883-0128 </td></tr><tr><td> סוללה במכונית 12-וולט </td><td></td><td></td><td> זמין באופן נרחב </td></tr><tr><td> מטען סוללה לרכב </td><td></td><td></td><td> זמין באופן נרחב </td></tr><tr><td></td><td></td><td></td><td> מגיב </td></tr><tr><td> נתרן כלורי (NaCl) </td><td> סיגמא </td><td> S7653 </td><td></td></tr><tr><td> HEPES </td><td> סיגמא </td><td> H3375 </td><td></td></tr><tr><td> דקסטרוז </td><td> סיגמא </td><td> G7528 </td><td></td></tr><tr><td> מגנזיום סולפט (MgSO 4) </td><td> סיגמא </td><td> M2643 </td><td></td></tr><tr><td> אשלגן זרח monobasic (KH 2 PO 4) </td><td> סיגמא </td><td> P5655 </td><td></td></tr><tr><td> אשלגן כלורי (KCl) </td><td> סיגמא </td><td> P9333 </td><td></td></tr><tr><td> dihydrate סידן כלוריד (CaCl 2 • 2H 2 0) </td><td> סיגמא </td><td> 223506 </td><td></td></tr><tr><td> hexahydrate מגנזיום כלוריד (MgCl 2 • 6H 2 0) </td><td> סיגמא </td><td> M2670 </td><td></td></tr><tr><td> EGTA </td><td> סיגמא </td><td> E0396 </td><td></td></tr></tbody></table>

single cell measurement of dopamine release with simultaneous voltage-clamp and amperometry

לאחר השחרור ל, דופמין המרווח הסינפטי מפעיל תכונות הביולוגיות שלו דרך יעדיה לפני ואחרי-הסינפטי 1. אות דופמין הוא הופסק על ידי דיפוזיה 2-3, אנזימים תאיים 4, ומובילים בממברנה 5. טרנספורטר דופאמין, הממוקם בחריץ שperi-הסינפטית של הנוירונים דופאמין מנקה את האמינים ישוחררו באמצעות שטף דופמין פנימה (ספיגה). טרנספורטר דופאמין יכול לעבוד גם בכיוון הפוך כדי לשחרר אמינים מבפנים החוצה בתהליך שנקרא תחבורה או זרימה של דופמין 5 כלפי חוץ. . יותר מ 20 שנים לפני זולצר et al דיווח טרנספורטר דופאמין יכול לפעול בשני מצבי פעילות: קדימה (ספיגה) והפוך (זרימה) 5. הנוירוטרנסמיטר משתחרר דרך הזרימה דרך טרנספורטר יכול להזיז כמות גדולה של דופמין למרחב החוץ התאי, והוכח לשחק תפקיד מרכזי בויסות דופמין h התאיomeostasis 6. כאן אנו מתארים כיצד מהדק תיקון זמני והקלטת amperometry יכולים לשמש למדידת דופמין שוחרר באמצעות מנגנון הזרימה עם רזולוצית זמן האלפית השנייה, כאשר פוטנציאל הממברנה נשלט. לשם כך, בהווה ובאותות חמצונים כל תאים (amperometric) נמדדים בו זמנית באמצעות מגבר 200B Axopatch (התקנים מולקולריים, עם סט נמוך לעבור Bessel מסנן ב1000 הרץ להקלטה נוכחית כל תאים). לamperometry הקלטת האלקטרודה סיבי פחמן מחובר למגבר שני (Axopatch 200B) וממוקמת בסמוך לממברנת הפלזמה ונערכה ב700 mV. הזרמים כל התא וחמצונים (amperometric) ניתן להקליט ויחסים נוכחי מתח יכולים להיות שנוצרו באמצעות פרוטוקול צעד מתח. בניגוד לכיול amperometric הרגיל, שדורש המרה לריכוז, הנוכחי הוא דיווח ישירות ללא התחשבות בנפח 7 היעילים. לפיכך, את הנתונים המתקבלמייצג גבול תחתון לזרימת דופאמין כי חלק המשדר הפסיד לפתרון התפזורת.

מהדק תיקון משולב עם amperometry יכול למדוד DA זרימת 2A מתח תלוי DAT בתיווך. איור מציג תצורת נציג ניסיוני והקלטה של DA זרימת DAT בתיווך כאשר הסביבה התאית ופוטנציאל הקרום הם הדקו ע&quot;י פיפטה תיקון כל תאים. באמצעות טכניקה זו, תאים לבטא חלבוני YFP-DAT הם מתח הדק עם פיפט...

Watch this Scientific Journal Video about Single Cell Measurement of Dopamine Release with Simultaneous Voltage-clamp and Amperometry at JoVE.com

Single Cell Measurement of Dopamine Release with Simultaneous Voltage-clamp and Amperometry

טכניקת amperometric מודדת שחרור דופאמין מתא בודד על ידי גילוי נוכחי חמצונים המיוצרים על ידי חמצון דופמין ספונטני. מהדק המתח סימולטני ומתודולוגיה amperometry לחשוף את מערכת היחסים בין מכניסטית &quot;הפעילות&quot; הכוללת של טרנספורטר דופאמין ותפקיד הרגולציה של פעילות זו על ההובלה ההפוכה של דופמין.

מדידת תא בודדה של שחרור דופמין במתח-clamp וAmperometry סימולטני

After its release into the synaptic cleft, dopamine exerts its biological properties via its pre- and post-synaptic targets1. The dopamine signal is ...

single-cell-measurement-dopamine-release-with-simultaneous-voltage

Research

JoVE Journal

Neuroscience

13.7K Views.  University of Florida. טכניקת amperometric מודדת שחרור דופאמין מתא בודד על ידי גילוי נוכחי חמצונים המיוצרים על ידי חמצון דופמין ספונטני. מהדק המתח סימולטני ומתודולוגיה amperometry לחשוף את מערכת היחסים בין מכניסטית "הפעילות" הכוללת של טרנספורטר דופאמין ותפקיד הרגולציה של פעילות זו על ההוב...

Video: Single Cell Measurement of Dopamine Release with Simultaneous Voltage-clamp and Amperometry

Functional Mapping with Simultaneous MEG and EEG

We use magnetoencephalography (MEG) and electroencephalography (EEG) to locate and determine the temporal evolution in brain areas involved in the processing of simple sensory stimuli. We will use somatosensory stimuli to locate the hand somatosensory areas, auditory stimuli to locate the auditory cortices, visual stimuli in four quadrants of the visual field to locate the early visual areas. These type of experiments are used for functional mapping in epileptic and brain tumor patients to locate eloquent cortices. In basic neuroscience similar experimental protocols are used to study the orchestration of cortical activity. The acquisition protocol includes quality assurance procedures, subject preparation for the combined MEG/EEG study, and acquisition of evoked-response data with somatosensory, auditory, and visual stimuli. We also demonstrate analysis of the data using the equivalent current dipole model and cortically-constrained minimum-norm estimates. Anatomical MRI data are employed in the analysis for visualization and for deriving boundaries of tissue boundaries for forward modeling and cortical location and orientation constraints for the minimum-norm estimates.

We use magnetoencephalography (MEG) and electroencephalography (EEG) to map brain areas involved in the processing of simple sensory stimuli.

מיפוי פונקציונלית עם מג סימולטני EEG

We use magnetoencephalography (MEG) and electroencephalography (EEG) to locate and determine the temporal evolution in brain areas involved in the ...

Presynaptic Dopamine Dynamics in Striatal Brain Slices with Fast-scan Cyclic Voltammetry

Extensive research has focused on the neurotransmitter dopamine because of its importance in the mechanism of action of drugs of abuse (e.g. cocaine and amphetamine), the role it plays in psychiatric illnesses (e.g. schizophrenia and Attention Deficit Hyperactivity Disorder), and its involvement in degenerative disorders like Parkinson's and Huntington's disease. Under normal physiological conditions, dopamine is known to regulate locomotor activity, cognition, learning, emotional affect, and neuroendocrine hormone secretion. One of the largest densities of dopamine neurons is within the striatum, which can be divided in two distinct neuroanatomical regions known as the nucleus accumbens and the caudate-putamen. The objective is to illustrate a general protocol for slice fast-scan cyclic voltammetry (FSCV) within the mouse striatum. FSCV is a well-defined electrochemical technique providing the opportunity to measure dopamine release and uptake in real time in discrete brain regions. Carbon fiber microelectrodes (diameter of ~ 7 &mu;m) are used in FSCV to detect dopamine oxidation. The analytical advantage of using FSCV to detect dopamine is its enhanced temporal resolution of 100 milliseconds and spatial resolution of less than ten microns, providing complementary information to in vivo microdialysis.

Using fast-scan cyclic voltammetry to measure electrically evoked presynaptic dopamine dynamics in striatal brain slices.

דופמין Dynamics Presynaptic בתוך פרוסות המוח striatal עם Voltammetry סריקה מהירה מחזורי

Extensive research has focused on the neurotransmitter dopamine because of its importance in the mechanism of action of drugs of abuse (e.g. cocaine and ...

Single-cell Profiling of Developing and Mature Retinal Neurons

Highly specialized, but exceedingly small populations of cells play important roles in many tissues. The identification of cell-type specific markers and gene expression programs for extremely rare cell subsets has been a challenge using standard whole-tissue approaches. Gene expression profiling of individual cells allows for unprecedented access to cell types that comprise only a small percentage of the total tissue1-7. In addition, this technique can be used to examine the gene expression programs that are transiently expressed in small numbers of cells during dynamic developmental transitions8.
This issue of cellular diversity arises repeatedly in the central nervous system (CNS) where neuronal connections can occur between quite diverse cells9. The exact number of distinct cell types is not precisely known, but it has been estimated that there may be as many as 1000 different types in the cortex itself10. The function(s) of complex neural circuits may rely on some of the rare neuronal types and the genes they express. By identifying new markers and helping to molecularly classify different neurons, the single-cell approach is particularly useful in the analysis of cell types in the nervous system. It may also help to elucidate mechanisms of neural development by identifying differentially expressed genes and gene pathways during early stages of neuronal progenitor development.
As a simple, easily accessed tissue with considerable neuronal diversity, the vertebrate retina is an excellent model system for studying the processes of cellular development, neuronal differentiation and neuronal diversification. However, as in other parts of the CNS, this cellular diversity can present a problem for determining the genetic pathways that drive retinal progenitors to adopt a specific cell fate, especially given that rod photoreceptors make up the majority of the total retinal cell population11. Here we report a method for the identification of the transcripts expressed in single retinal cells (Figure 1). The single-cell profiling technique allows for the assessment of the amount of heterogeneity present within different cellular populations of the retina2,4,5,12. In addition, this method has revealed a host of new candidate genes that may play role(s) in the cell fate decision-making processes that occur in subsets of retinal progenitor cells8. With some simple adjustments to the protocol, this technique can be utilized for many different tissues and cell types.

A method for the isolation of single retinal cells and subsequent amplification of their cDNAs is described. Single-cell transcriptomics reveals the degree of cellular heterogeneity present in a tissue and uncovers new marker genes for rare cell populations. The accompanying protocol can be adjusted to suit many different cell types.

מתא בודד פרופיל של נוירונים רשתית מתפתחות מבוגרים

Highly specialized, but exceedingly small populations of cells play important roles in many tissues. The identification of cell-type specific markers and ...

Optical Recording of Suprathreshold Neural Activity with Single-cell and Single-spike Resolution

Signaling of information in the vertebrate central nervous system is often carried by populations of neurons rather than individual neurons. Also propagation of suprathreshold spiking activity involves populations of neurons. Empirical studies addressing cortical function directly thus require recordings from populations of neurons with high resolution. Here we describe an optical method and a deconvolution algorithm to record neural activity from up to 100 neurons with single-cell and single-spike resolution. This method relies on detection of the transient increases in intracellular somatic calcium concentration associated with suprathreshold electrical spikes (action potentials) in cortical neurons. High temporal resolution of the optical recordings is achieved by a fast random-access scanning technique using acousto-optical deflectors (AODs)1. Two-photon excitation of the calcium-sensitive dye results in high spatial resolution in opaque brain tissue2. Reconstruction of spikes from the fluorescence calcium recordings is achieved by a maximum-likelihood method. Simultaneous electrophysiological and optical recordings indicate that our method reliably detects spikes (&gt;97% spike detection efficiency), has a low rate of false positive spike detection (&lt; 0.003 spikes/sec), and a high temporal precision (about 3 msec) 3. This optical method of spike detection can be used to record neural activity in vitro and in anesthetized animals in vivo3,4.

Understanding the function of the vertebrate central nervous system requires recordings from many neurons because cortical function arises on the level of populations of neurons. Here we describe an optical method to record suprathreshold neural activity with single-cell and single-spike resolution, dithered random-access scanning. This method records somatic fluorescence calcium signals from up to 100 neurons with high temporal resolution. A maximum-likelihood algorithm deconvolves the underlying suprathreshold neural activity from the somatic fluorescence calcium signals. This method reliably detects spikes with high detection efficiency and a low rate of false positives and can be used to study neural populations in vitro and in vivo.

הקלטה אופטית של פעילות עצבית suprathreshold עם רזולוצית תא בודד ויחיד ספייק

Signaling of information in the vertebrate central nervous system is often carried by populations of neurons rather than individual neurons. Also ...

Simultaneous Electroencephalography, Real-time Measurement of Lactate Concentration and Optogenetic Manipulation of Neuronal Activity in the Rodent Cerebral Cortex

Although the brain represents less than 5% of the body by mass, it utilizes approximately one quarter of the glucose used by the body at rest1. The function of non rapid eye movement sleep (NREMS), the largest portion of sleep by time, is uncertain. However, one salient feature of NREMS is a significant reduction in the rate of cerebral glucose utilization relative to wakefulness2-4. This and other findings have led to the widely held belief that sleep serves a function related to cerebral metabolism. Yet, the mechanisms underlying the reduction in cerebral glucose metabolism during NREMS remain to be elucidated.
	One phenomenon associated with NREMS that might impact cerebral metabolic rate is the occurrence of slow waves, oscillations at frequencies less than 4 Hz, in the electroencephalogram5,6. These slow waves detected at the level of the skull or cerebral cortical surface reflect the oscillations of underlying neurons between a depolarized/up state and a hyperpolarized/down state7. During the down state, cells do not undergo action potentials for intervals of up to several hundred milliseconds. Restoration of ionic concentration gradients subsequent to action potentials represents a significant metabolic load on the cell8; absence of action potentials during down states associated with NREMS may contribute to reduced metabolism relative to wake.
	Two technical challenges had to be addressed in order for this hypothetical relationship to be tested. First, it was necessary to measure cerebral glycolytic metabolism with a temporal resolution reflective of the dynamics of the cerebral EEG (that is, over seconds rather than minutes). To do so, we measured the concentration of lactate, the product of aerobic glycolysis, and therefore a readout of the rate of glucose metabolism in the brains of mice. Lactate was measured using a lactate oxidase based real time sensor embedded in the frontal cortex. The sensing mechanism consists of a platinum-iridium electrode surrounded by a layer of lactate oxidase molecules. Metabolism of lactate by lactate oxidase produces hydrogen peroxide, which produces a current in the platinum-iridium electrode. So a ramping up of cerebral glycolysis provides an increase in the concentration of substrate for lactate oxidase, which then is reflected in increased current at the sensing electrode. It was additionally necessary to measure these variables while manipulating the excitability of the cerebral cortex, in order to isolate this variable from other facets of NREMS.
	We devised an experimental system for simultaneous measurement of neuronal activity via the elecetroencephalogram, measurement of glycolytic flux via a lactate biosensor, and manipulation of cerebral cortical neuronal activity via optogenetic activation of pyramidal neurons. We have utilized this system to document the relationship between sleep-related electroencephalographic waveforms and the moment-to-moment dynamics of lactate concentration in the cerebral cortex. The protocol may be useful for any individual interested in studying, in freely behaving rodents, the relationship between neuronal activity measured at the electroencephalographic level and cellular energetics within the brain.

A procedure is described for manipulating the activity of cerebral cortical pyramidal neurons optogenetically while the electroencephalogram, electromyogram, and cerebral lactate concentration are monitored. Experimental recordings are performed on cable-tethered mice while they undergo spontaneous sleep/wake cycles. Optogenetic equipment is assembled in our laboratory; recording equipment is commercially available.

Electroencephalography סימולטני, מדידה בזמן אמת של הריכוז לקטט ומניפולצית Optogenetic של פעילות עצבית בקליפת המוח המכרסמת

Although the brain represents less than 5% of the body  by mass, it utilizes approximately one quarter of the glucose used by the body  at rest1. The ...

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.

גירוי מוחי עמוק עם fMRI סימולטני במכרסמים

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

Preparation of Neuronal Co-cultures with Single Cell Precision

Microfluidic embodiments of the Campenot chamber have attracted great interest from the neuroscience community. These interconnected co-culture platforms can be used to investigate a variety of questions, spanning developmental and functional neurobiology to infection and disease propagation. However, conventional systems require significant cellular inputs (many thousands per compartment), inadequate for studying low abundance cells, such as primary dopaminergic substantia nigra, spiral ganglia, and Drosophilia melanogaster neurons, and impractical for high throughput experimentation. The dense cultures are also highly locally entangled, with few outgrowths (&#60;10%) interconnecting the two cultures. In this paper straightforward microfluidic and patterning protocols are described which address these challenges: (i) a microfluidic single neuron arraying method, and (ii) a water masking method for plasma patterning biomaterial coatings to register neurons and promote outgrowth between compartments. Minimalistic neuronal co-cultures were prepared with high-level (&#62;85%) intercompartment connectivity and can be used for high throughput neurobiology experiments with single cell precision.

Protocols for single neuron microfluidic arraying and water masking for the in-chip plasma patterning of biomaterial coatings are described. Highly interconnected co-cultures can be prepared using minimal cell inputs.

הכנת עצבית שיתוף תרבויות עם Precision תא בודד

Microfluidic embodiments of the Campenot chamber have attracted great interest from the neuroscience community. These interconnected co-culture platforms ...

Simultaneous Detection of c-Fos Activation from Mesolimbic and Mesocortical Dopamine Reward Sites Following Naive Sugar and Fat Ingestion in Rats

This study uses cellular c-fos activation to assess effects of novel ingestion of fat and sugar on brain dopamine (DA) pathways in rats. Intakes of sugars and fats are mediated by their innate attractions as well as learned preferences. Brain dopamine, especially meso-limbic and meso-cortical projections from the ventral tegmental area (VTA), has been implicated in both of these unlearned and learned responses. The concept of distributed brain networks, wherein several sites and transmitter/peptide systems interact, has been proposed to mediate palatable food intake, but there is limited evidence empirically demonstrating such actions. Thus, sugar intake elicits DA release and increases c-fos-like immunoreactivity (FLI) from individual VTA DA projection zones including the nucleus accumbens (NAC), amygdala (AMY) and medial prefrontal cortex (mPFC) as well as the dorsal striatum. Further, central administration of selective DA receptor antagonists into these sites differentially reduce acquisition and expression of conditioned flavor preferences elicited by sugars or fats. One approach by which to determine whether these sites interacted as a distributed brain network in response to sugar or fat intake would be to simultaneous evaluate whether the VTA and its major mesotelencephalic DA projection zones (prelimbic and infralimbic mPFC, core and shell of the NAc, basolateral and central-cortico-medial AMY) as well as the dorsal striatum would display coordinated and simultaneous FLI activation after oral, unconditioned intake of corn oil (3.5%), glucose (8%), fructose (8%) and saccharin (0.2%) solutions. This approach is a successful first step in identifying the feasibility of using cellular c-fos activation simultaneously across relevant brain sites to study reward-related learning in ingestion of palatable food in rodents.

The goal of this study is to identify reward-related distributed brain networks by delineating a reliable immunohistological technique using cellular c-fos activation to measure simultaneous changes in dopamine pathways and terminal sites after novel ingestion of fat and sugar in rats.

זיהוי סימולטני של הפעלת ג-Fos מאתרים זכו דופמין Mesolimbic ו Mesocortical בעקבות סוכר נאיבי בליעת שומן אצל חולדות

This study uses cellular c-fos activation to assess effects of novel ingestion of fat and sugar on brain dopamine (DA) pathways in rats. Intakes of sugars ...

Electrophysiological Method for Whole-cell Voltage Clamp Recordings from Drosophila Photoreceptors

Whole-cell voltage clamp recordings from Drosophila melanogaster photoreceptors have revolutionized the field of invertebrate visual transduction, enabling the use of D. melanogaster molecular genetics to study inositol-lipid signaling and Transient Receptor Potential (TRP) channels at the single-molecule level. A handful of labs have mastered this powerful technique, which enables the analysis of the physiological responses to light under highly controlled conditions. This technique allows control over the intracellular and extracellular media; the membrane voltage; and the fast application of pharmacological compounds, such as a variety of ionic or pH indicators, to the intra- and extracellular media. With an exceptionally high signal-to-noise ratio, this method enables the measurement of dark spontaneous and light-induced unitary currents (i.e.&#160;spontaneous and quantum bumps) and macroscopic Light-induced Currents (LIC) from single D. melanogaster photoreceptors. This protocol outlines, in great detail, all the key steps necessary to perform this technique, which includes both electrophysiological and optical recordings. The fly retina dissection procedure for the attainment of intact and viable ex vivo isolated ommatidia in the bath chamber is described. The equipment needed to perform whole-cell and fluorescence imaging measurements are also detailed. Finally, the pitfalls in using this delicate preparation during extended experiments are explained.

Electrophysiological Method for Whole-cell Voltage Clamp Recordings from Drosophila Photoreceptors

Whole-cell recordings from Drosophila melanogaster photoreceptors enable the measurement of spontaneous dark bumps, quantum bumps, macroscopic responses to light, and current-voltage relationships under various conditions. In combination with D. melanogaster genetic manipulation tools, this method enables the study of the ubiquitous inositol-lipid signaling pathway and its target, the TRP channel.

שיטה אלקטרו-קולית לקולקציית מתח מלא<em&gt; תסיסנית</em&gt; פוטורספטורים

Whole-cell voltage clamp recordings from Drosophila melanogaster photoreceptors have revolutionized the field of invertebrate visual transduction, ...

Levator Auris Longus Preparation for Examination of Mammalian Neuromuscular Transmission Under Voltage Clamp Conditions

This protocol describes a technique to record synaptic transmission from the neuromuscular junction under current-clamp and voltage-clamp conditions. An ex vivo preparation of the levator auris longus (LAL) is used because it is a thin muscle that provides easy visualization of the neuromuscular junction for microelectrode impalement at the motor endplate. This method allows for the recording of spontaneous miniature endplate potentials and currents (mEPPs and mEPCs), nerve-evoked endplate potentials and currents (EPPs and EPCs), as well as the membrane properties of the motor endplate. Results obtained from this method include the quantal content (QC), number of vesicle release sites (n), probability of vesicle release (prel), synaptic facilitation and depression, as well as the muscle membrane time constant (&#964;m) and input resistance. Application of this technique to mouse models of human disease can highlight key pathologies in disease states and help identify novel treatment strategies. By fully voltage-clamping a single synapse, this method provides one of the most detailed analyses of synaptic transmission currently available.

Levator Auris Longus Preparation for Examination of Mammalian Neuromuscular Transmission Under Voltage Clamp Conditions

The protocol described in this paper uses the mouse levator auris longus (LAL) muscle to record spontaneous and nerve-evoked postsynaptic potentials (current-clamp) and currents (voltage-clamp) at the neuromuscular junction. Use of this technique can provide key insights into mechanisms of synaptic transmission under normal and disease conditions.

מרים Auris הארוך הכנה לקראת בחינת בתרבית של התמסורת Neuromuscular בתנאים קלאמפ מתח

This protocol describes a technique to record synaptic transmission from the neuromuscular junction under current-clamp and voltage-clamp conditions. An ...