Substance P antagonist inhibits vasomotor responses elicited from ventral medulla in rat.
Application of kainic acid to the ventral medulla in rats leads to increases in blood pressure and heart rate. These responses can be attenuated or reversed by infusion of the substance P antagonist--(D-Pro2,D-Trp7,9)-substance P into the spinal subarachnoid space. Kainic acid elicits normal pressor responses from rats that have been treated intracisternally with the serotonin neurotoxin 5,7-dihydroxytryptamine. These results suggest that the substance P-like neurons of the ventral medulla may play a role in maintaining vasomotor tone.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D007608:Kainic Acid / Q000633:toxicity; D008526:Medulla Oblongata / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D013116:Spinal Cord / Q000187:drug effects; D013373:Substance P / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects*
D013373:Substance P; D007608:Kainic Acid