JN Fuel your research with LabChart
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Neurophysiol 60: 2196-2210, 1988;
0022-3077/88 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Pawson, P. A.
Right arrow Articles by Chase, R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Pawson, P. A.
Right arrow Articles by Chase, R.

Journal of Neurophysiology, Vol 60, Issue 6 2196-2210, Copyright © 1988 by APS

ARTICLES

The development of transmission at an identified molluscan synapse. I. The emergence of synaptic plasticities

P. A. Pawson and R. Chase
Department of Biology, McGill University, Montreal, Quebec, Canada.

1. A monosynaptic, chemical synapse exists between two identified neurons in the subesophageal ganglia of the pulmonate mollusc, Achatina fulica. The snail undergoes a direct development, i.e., there is no intervening metamorphic period. The presynaptic (V2) and postsynaptic (RPr1) cells are two of the largest neurons found in the ganglia. The development of transmission at this synapse was studied from the last one-third of embryonic life to adulthood. 2. Synaptic transmission was studied by eliciting an action potential in V2 and recording the resultant excitatory postsynaptic potential (EPSP) in RPr1. In a train of repetitive stimuli, the ratio of the mean amplitude of the second EPSP to that of the first EPSP (EPSP2/EPSP1) is always greater than 1, indicating that short-term facilitation is present at all developmental ages studied. Following the initial short-term facilitation, embryonic synapses undergo a profound synaptic depression. Postembryonically there is a progressive increase in the amount of frequency facilitation with age, suggesting that the synapse shows a developmental trend towards an increased capacity for transmitter release. 3. In contrast to the progressive growth of frequency facilitation, the amplitude of the first EPSP in a series of responses (EPSP1) is not significantly related to age. 4. When transmitter release is reduced to approximately 25% of normal levels by a low-Ca2+/high-Mg2+ saline, the synaptic depression that is observed in the younger synapses disappears and is replaced by an adult-like frequency facilitation. 5. The adult synapse displays a phenomenon similar to posttetanic potentiation, which we refer to as the "retention of frequency facilitation." If an initial train of 150 stimuli at 0.2 Hz is followed by a second, identical train after an interval of 1 h, the postsynaptic response is greater during the second train than during the first. This phenomenon only becomes apparent in the second month after hatching, indicating that this separate synaptic plasticity develops at a different rate than does frequency facilitation.


This article has been cited by other articles:


Home page
 J. Neurosci.Home page
A. Reyes and B. Sakmann
Developmental Switch in the Short-Term Modification of Unitary EPSPs Evoked in Layer 2/3 and Layer 5 Pyramidal Neurons of Rat Neocortex
J. Neurosci., May 15, 1999; 19(10): 3827 - 3835.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online