Substance P as a neuromodulator of cerebellar cholinergic systems.
Substance P in low concentrations (10(-7)M) activates rat cerebellar neurons (in slices), while in high concentrations (10(-6)and 10(-5)M) this compound causes a biphasic response (excitation-inhibition). Substance P probably acts as the excitatory neurotransmitter in the cerebellum and produces modulatory effects (triggering and facilitation) on cerebellar cholinergic structures. Substance P reactivates cholinergic excitatory processes, while acetylcholine prevents substance P-induced inhibitory phase. The data suggest that the modulatory effects of substance P are realized via the feedback mechanisms.
Vlasova
I G
IG
Department of Normal Physiology, Patrice Lumumba People's Friendship University, Moscow, Russia.
Dolgopol'skii
A L
AL
D000109:Acetylcholine / Q000378:metabolism / Q000494:pharmacology; D000818:Animals; D002531:Cerebellum / Q000187:drug effects / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004594:Electrophysiology; D018377:Neurotransmitter Agents / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology*; D011689:Purkinje Cells / Q000187:drug effects / Q000502:physiology; D051381:Rats; D011950:Receptors, Cholinergic / Q000378:metabolism*; D013373:Substance P / Q000378:metabolism / Q000494:pharmacology / Q000502:physiology*
D018377:Neurotransmitter Agents; D011950:Receptors, Cholinergic; D013373:Substance P; D000109:Acetylcholine