A modulatory role of central cholinergic transmission in control of the 10-Hz rhythm in sympathetic nerve discharge.
In 43 urethane-anesthetized or decerebrate, baroreceptor-denervated cats, spectral analysis showed that most of the power in sympathetic nerve discharge (SND) was at frequencies < 6 Hz. In 18 of these cats, physostigmine (100 micrograms/kg i.v.) induced a 10-Hz rhythm in inferior cardiac SND that was eliminated by atropine sulfate (0.25 mg/kg i.v.; n = 6). In contrast, the naturally occurring 10-Hz rhythm that appeared in SND in other experiments was atropine-insensitive (n = 6). The data indicate that central muscarinic cholinergic transmission is not essential for the naturally occurring 10-Hz rhythm. Nonetheless, facilitation of cholinergic transmission can induce a 10-Hz rhythm.
Orer
H S
HS
Department of Pharmacology and Toxicology, Michigan State University, East Lansing 48824-1317.
Barman
S M
SM
Zhong
S
S
Gebber
G L
GL
D000818:Animals; D001285:Atropine / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D002415:Cats; D003655:Decerebrate State; D003714:Denervation; D006321:Heart / Q000187:drug effects / Q000294:innervation*; D006339:Heart Rate / Q000187:drug effects; D008636:Mesencephalon; D010830:Physostigmine / Q000494:pharmacology*; D011311:Pressoreceptors / Q000502:physiology*; D013233:Stellate Ganglion / Q000187:drug effects / Q000502:physiology*; D009435:Synaptic Transmission / Q000187:drug effects*
D001285:Atropine; D010830:Physostigmine