Effects of anticholinergic drugs on rabbit efferent phrenic discharges.
In conscious, vagotomized, curarized, and artificially-ventilated rabbits, the efferent phrenic discharges were recorded. When scopolamine, atropine, pirenzepine or AF-DX 116 (11-2[[2-[(diethylamino)methyl]-1-piperidinyl]acetyl]-5,11-dihydro- 6H[2,3-6] [1,4]benzodiazepine-6-one) was injected into the cerebello-medullary cistern, the frequency and voltage of phrenic discharges were decreased (P less than 0.05) by scopolamine (0.5 mg.kg-1) and pirenzepine (0.5 mg.kg-1), but were increased (P less than 0.01) by atropine (0.05 mg.kg-1) and AF-DX 116 (0.1 mg.kg-1). It is probable that scopolamine inhibits the respiratory center by blocking the M1 cholinergic receptors while atropine excites the respiratory center blocking the M2 cholinergic receptors.
Bian
C F
CF
Department of Neuropharmacology, Xuzhou Medical College, China.
Zhou
J
J
Hong
X M
XM
Yin
X X
XX
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D004594:Electrophysiology; D005260:Female; D007276:Injections, Intraventricular; D008297:Male; D010791:Phrenic Nerve / Q000187:drug effects* / Q000502:physiology; D010890:Pirenzepine / Q000031:analogs & derivatives / Q000494:pharmacology; D011817:Rabbits; D012125:Respiratory Center / Q000187:drug effects; D012601:Scopolamine / Q000494:pharmacology*; D014628:Vagotomy
D010890:Pirenzepine; D001285:Atropine; D012601:Scopolamine; C048593:otenzepad