Substance P antagonist (spantide) suppresses the compound action potentials of the rat sciatic nerve in vitro.
We examined the effects of substance P, [D-Arg1, D-Trp7, 9, Leu1 1] substance P (spantide) and lidocaine on the compound action potentials (APcs) of the rat sciatic nerve in vitro. Substance P had no effect but spantide suppressed the APcs of both A- and C-fibers in a dose-dependent manner and this suppression was reversible at 10(-4) M but irreversible at 10(-3) M. Lidocaine also suppressed the APcs reversibly but spantide was more potent than lidocaine. There seemed to be differences in the suppressing mechanism between the two drugs.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D066298:In Vitro Techniques; D008012:Lidocaine / Q000494:pharmacology; D009412:Nerve Fibers / Q000187:drug effects / Q000502:physiology; D009431:Neural Conduction / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D012584:Sciatic Nerve / Q000187:drug effects / Q000502:physiology*; D013373:Substance P / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors* / Q000494:pharmacology
D013373:Substance P; C042867:spantide; D008012:Lidocaine