title: Effects of a substance P analogue with antagonist properties ([D-Arg1, D-Trp7,9, Leu11]substance P) on spontaneous activity of the adrenal sympathetic nerve and its evoked reflex discharges in response to somatic afferent stimulation.
abstract: The present study was designed to test the effect of a substance P (SP) antagonist, [D-Arg1, D-Trp7,9, Leu11]substance P (Spantide), on spontaneous efferent activity of adrenal sympathetic nerve and the two A- and C-sympathetic reflex components evoked in adrenal sympathetic nerve by stimulation of myelinated A- and unmyelinated C-afferent nerve fibers of a hindlimb nerve, respectively, in anesthetized rats. The spontaneous adrenal nerve activity and both of the A- and C-sympathetic reflex components were proportionally reduced by intrathecal application of the SP antagonist (0.038-0.76 nmol), although the same doses did not affect A- and C-somatic reflex components. These data suggest that the SP antagonist has a greater effect on SP-containing neurons related to the generation of spontaneous activity of sympathetic neurons and somato-sympathetic reflex pathways than on SP-containing primary somatic afferent nerves and somato-somatic reflex pathways.
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000311:Adrenal Glands / Q000294:innervation*; D000320:Adrenergic Fibers / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D004558:Electric Stimulation; D066298:In Vitro Techniques; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012023:Reflex, Monosynaptic / Q000187:drug effects*; D013373:Substance P / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D013497:Sural Nerve / Q000187:drug effects / Q000502:physiology
chemical_list: D013373:Substance P; C042867:spantide