HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Supplemental Figures All Versions of this Article: 98/6/3349    most recent 00898.2007v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (9) Citing Articles via Google Scholar Google Scholar Articles by Renden, R. Articles by von Gersdorff, H. Search for Related Content PubMed PubMed Citation Articles by Renden, R. Articles by von Gersdorff, H.

Synaptic Vesicle Endocytosis at a CNS Nerve Terminal: Faster Kinetics at Physiological Temperatures and Increased Endocytotic Capacity During Maturation

The Vollum Institute, Oregon Health and Science University, Portland, Oregon

Submitted 10 August 2007; accepted in final form 6 October 2007

Synaptic vesicle membrane must be quickly retrieved and recycled after copious exocytosis to limit the depletion of vesicle pools. The rate of endocytosis at the calyx of Held nerve terminal has been measured directly using membrane capacitance measurements from immature postnatal day P7–P10 rat pups at room temperature (RT: 23–24°C). This rate has an average time constant of tens of seconds and becomes slower when the amount of exocytosis (measured as capacitance jump) increases. Such slow rates seem paradoxical for a synapse that can operate continuously at high-input frequencies. Here we perform time-resolved membrane capacitance measurements from the mouse calyx of Held in brain stem slices at physiological temperature (PT: 35–37°C), and also from more mature calyces after the onset of hearing (P14–P18). Our results show that the rate of endocytosis is strongly temperature dependent, whereas the endocytotic capacity of a nerve terminal is dependent on developmental stage. At PT we find that endocytosis accelerates due to the addition of a kinetically fast component (time constant: = 1–2 s) immediately after exocytosis. Surprisingly, we find that at RT the rate of endocytosis triggered by short (1- to 5-ms) or long (10-ms) depolarizing pulses in P14–P18 mice are similar ( 15 s). Furthermore, this rate is greatly accelerated at PT ( 2 s). Thus endocytosis becomes faster and less saturable during synaptic maturation, making the calyceal terminal more capable of sustaining prolonged high-frequency transmitter release.

This article has been cited by other articles:

				M. A. Gaffield, L. Tabares, and W. J. Betz The spatial pattern of exocytosis and post-exocytic mobility of synaptopHluorin in mouse motor nerve terminals J. Physiol., March 15, 2009; 587(6): 1187 - 1200. [Abstract] [Full Text] [PDF]

				X. Lou, S. Paradise, S. M. Ferguson, and P. De Camilli Selective saturation of slow endocytosis at a giant glutamatergic central synapse lacking dynamin 1 PNAS, November 11, 2008; 105(45): 17555 - 17560. [Abstract] [Full Text] [PDF]

				M. H. Hennig, M. Postlethwaite, I. D. Forsythe, and B. P. Graham Interactions between multiple sources of short-term plasticity during evoked and spontaneous activity at the rat calyx of Held J. Physiol., July 1, 2008; 586(13): 3129 - 3146. [Abstract] [Full Text] [PDF]