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Pharmacology 9 by springer-verlag 1980 presynaptic actions of 4-aminopyridine and t-aminobutyric acid on rat sympathetic ganglia in vitro.
| Content Provider | CiteSeerX |
|---|---|
| Author | Galvan, M. Grafe, P. Bruggencate, G. Ten |
| Abstract | Summary. Responses to bath-applications f 4-amino-pyridine (4-AP) and y-aminobutyric acid (GABA) were recorded intracellularly from neurones in the rat isol-ated superior cervical ganglion. 4-aminopyridine (0.1- 1.0 mmol/1) usually induced spontaneous action potentials and excitatory postsyn-aptic potentials (EPSPs), which were blocked by hexamethonium. Membrane potential was unchanged; spike duration was slightly increased. Vagus nerve B-and C-fibre potentials were prolonged. In 4-AP solution (0.1- 0.3 mmol/1), GABA (0.1 mmol/1), 3-aminopropanesulphonic ac dor mus-cimol evoked "bursts " of spikes and EPSPs in addition to a neuronal depolarization. These "bursts", which were not elicited by glycine, glutamate, taurine or (+)-baclofen, were completely antagonised by hexa-methonium, tetrodotoxin or bicuculline metho-chloride. It is concluded that: (a)4-AP has a potent pre-synaptic action on sympathetic ganglia; (b) presynaptic actions of GABA can be recorded postsynaptically in the presence of 4-AP; and (c) the presynaptic GABA-receptors revealed in this condition are similar to those on the postsynaptic membrane. |
| File Format | |
| Access Restriction | Open |
| Subject Keyword | Presynaptic Action T-aminobutyric Acid Rat Sympathetic Ganglion Postsynaptic Membrane Presynaptic Gaba-receptors Rat Isol-ated Superior Cervical Ganglion Potent Pre-synaptic Action Membrane Potential Y-aminobutyric Acid 3-aminopropanesulphonic Ac Dor Mus-cimol Excitatory Postsyn-aptic Potential 4-ap Solution Spike Duration B-and C-fibre Potential Neuronal Depolarization Spontaneous Action Potential Sympathetic Ganglion |
| Content Type | Text |
