|
|
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
The Pharmacology of Efferent Synapses in the Lateral-Line System of Xenopus Laevis
1 Department of Zoology, University of Cambridge
1. The nature of the transmitter substance released at the lateral-line efferent synapses was investigated by histochemical techniques in Xenopus and Acerina and by pharmacological methods in Xenopus.
2. The bases of lateral-line hair-cells and fine fibres in the lateral-line nerves reacted positively for acetylcholinesterase in Acerina and to a lesser extent in Xenopus.
3. Acetylcholine (10-6M, and acetyl-
-methyl choline (5 x 10-6M), which has a muscarinic action, caused strong reversible inhibition of afferent impulses when pipetted on to the undersides of lateral-line stitches. Carbachol (5 x 10-4 to 5 x 10-5M) caused a smaller reversible inhibition of spontaneous afferent impulses, but other nicotinic substances (propionylcholine and buterylcholine) had no effect.
4. Physostigmine (5 x 10-5M) prolonged inhibition of afferent impulses by electrical stimulation of efferent fibres, but atropine (5 x 10-6M) blocked it.
5. Calcium and magnesium interact at the efferent synapses in a way similar to that found at the amphibian neuromuscular junction.
6. Arguments are put forward to support the hypothesis that acetylcholine is released at lateral-line efferent synapses.
Submitted on October 20, 1970
This article has been cited by other articles:
![]() |
J. M. McIntosh, P. V. Plazas, M. Watkins, M. E. Gomez-Casati, B. M. Olivera, and A. B. Elgoyhen A Novel {alpha}-Conotoxin, PeIA, Cloned from Conus pergrandis, Discriminates between Rat {alpha}9{alpha}10 and {alpha}7 Nicotinic Cholinergic Receptors J. Biol. Chem., August 26, 2005; 280(34): 30107 - 30112. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Dawkins, S. L. Keller, and W. F. Sewell Pharmacology of Acetylcholine-Mediated Cell Signaling in the Lateral Line Organ Following Efferent Stimulation J Neurophysiol, May 1, 2005; 93(5): 2541 - 2551. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Dawkins and W. F. Sewell Afferent Synaptic Transmission in a Hair Cell Organ: Pharmacological and Physiological Analysis of the Role of the Extended Refractory Period J Neurophysiol, August 1, 2004; 92(2): 1105 - 1115. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. P. Bailey and W. F. Sewell Calcitonin Gene-Related Peptide Suppresses Hair Cell Responses to Mechanical Stimulation in the Xenopus Lateral Line Organ J. Neurosci., July 1, 2000; 20(13): 5163 - 5169. [Abstract] [Full Text] [PDF] |
||||