[Ventrobulbular hypotensive action of muscimol].
Muscimol, a rigid analogue of GABA has been injected in the CNS of urethane anesthetized, normotensive cats. Injected either intracisternally (1 or 2 microgram/kg, 0.05 ml) or directly by microinjection in a restricted ventrolateral region of the brain stem (0.5 or 1 microgram/kg, 0.5 microliter), muscimol induced hypotension and bradycardia. These central cardiovascular effects of muscimol were antagonized by bicuculline, a "specific" GABA antagonist agent. These data emphasize the involvement of gabergic mechanisms in the central cardiovascular control, at least in the ventrolateral part of the medulla oblongata.
D000818:Animals; D001919:Bradycardia / Q000139:chemically induced / Q000503:physiopathology*; D001933:Brain Stem / Q000187:drug effects / Q000503:physiopathology*; D002415:Cats; D005260:Female; D007022:Hypotension / Q000139:chemically induced / Q000503:physiopathology*; D008297:Male; D009118:Muscimol / Q000494:pharmacology*; D010080:Oxazoles / Q000494:pharmacology*
D010080:Oxazoles; D009118:Muscimol
Action hypotensive ventrobulbaire du muscimol.