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) All Versions of this Article: 565/3/743    most recent jphysiol.2005.087296v1 Services Email this article to a friend Similar articles in this journal 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 Google Scholar Google Scholar Articles by Teng, H. Articles by Wilkinson, R. S Search for Related Content PubMed PubMed Citation Articles by Teng, H. Articles by Wilkinson, R. S

¹ Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, USA

At the snake neuromuscular junction, low temperature (LT, 5–7°C) blocks clathrin-mediated endocytosis (CME) while exocytosis is largely unaffected. Thus compensatory endocytosis that normally follows transmitter release is inhibited, or ‘delayed’ until the preparation is warmed to room temperature (RT). This delay was exploited to observe how changes in bulk [Ca²⁺]_i directly affect CME. Motor terminals were loaded with fura-2 to monitor [Ca²⁺]_i. With brief stimulation at LT, [Ca²⁺]_i transiently increased but returned to baseline (63 nM) in < 8 min. After 15 min at LT, [Ca²⁺]_i was altered by incubating preparations in the Ca²⁺ ionophore ionomyocin. Preparations were then warmed to RT to initiate delayed endocytosis, which was quantified as uptake of the fluorescent optical probe sulforhodamine 101. Endocytosis was more rapid when [Ca²⁺]_i increased; the rate at 300 nM Ca²⁺ was double that under basal conditions. Thus the rate of CME – isolated from stimulation, transmitter release, and other forms of endocytosis – is directly influenced by intraterminal Ca²⁺.

(Received 23 March 2005; accepted after revision 26 April 2005; first published online 28 April 2005)
Corresponding author R. S. Wilkinson: Department of Cell Biology and Physiology, Washington University School of Medicine, 660 South Euclid Ave., Box 8228, St. Louis, MO 63110, USA. Email: wilk{at}wustl.edu

This article has been cited by other articles:

				R. Renden and H. von Gersdorff Synaptic Vesicle Endocytosis at a CNS Nerve Terminal: Faster Kinetics at Physiological Temperatures and Increased Endocytotic Capacity During Maturation J Neurophysiol, December 1, 2007; 98(6): 3349 - 3359. [Abstract] [Full Text] [PDF]