Pharmacological properties of the homomeric alpha 7 receptor.
The pharmacological properties of the alpha-bungarotoxin sensitive alpha 7 neuronal nicotinic acetylcholine receptor (nAChR) were studied upon reconstitution in Xenopus oocytes. Channels formed by alpha 7 are about 10-fold more sensitive to nicotine and cytisine than to ACh but are little, if at all, activated by the ganglionic agonist 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP). Tubocurarine (TC) was found to act as a non-competitive inhibitor, whereas dihydro-beta-erythroidine (DH beta E) behaves as a pure competitive inhibitor whose blockade is fast and fully reversible. In addition, the alpha 7 receptor displays a poor sensitivity to methonium salts. The pharmacological properties of the alpha 7 channels are readily distinguishable from those of other identified neuronal nicotinic receptors.
Bertrand
D
D
Department of Physiology, CMU, Geneva, Switzerland.
Bertrand
S
S
Ballivet
M
M
D000109:Acetylcholine / Q000494:pharmacology; D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D001392:Azocines; D004079:Dihydro-beta-Erythroidine / Q000494:pharmacology; D004246:Dimethylphenylpiperazinium Iodide / Q000494:pharmacology; D006584:Hexamethonium Compounds / Q000494:pharmacology; D009538:Nicotine / Q000494:pharmacology; D009865:Oocytes / Q000187:drug effects; D011807:Quinolizines; D011950:Receptors, Cholinergic; D011978:Receptors, Nicotinic / Q000187:drug effects*; D014403:Tubocurarine / Q000494:pharmacology; D014981:Xenopus; D000093843:Quinolizidine Alkaloids
D000109:Acetylcholine; D000470:Alkaloids; D001392:Azocines; D004079:Dihydro-beta-Erythroidine; D004246:Dimethylphenylpiperazinium Iodide; D006584:Hexamethonium Compounds; D009538:Nicotine; D011807:Quinolizines; D011950:Receptors, Cholinergic; D011978:Receptors, Nicotinic; D014403:Tubocurarine; C004712:cytisine; D000093843:Quinolizidine Alkaloids