title: Lack of algesic effect of substance P on paravascular pain receptors.
abstract: 1. Substance P (synthetic or extracted for intestine or central nervous system) is devoid of an algesic effect on paravascular pain receptors. 2. The algesic effect of a AP-containing acetone HCl-extract from spinal cord is explained by its high content of potassium ions. 3. SP-containing preparations which include an ammonium sulphate precipitation in the extraction procedure are algesic due to content of this salt. 4. SP-containing extract from intestine were found to be contaminated with a bradykinin-like peptide of high algesic potency. 5. These findings are discussed with regard to the restricted value of earlier results about central actions of SP-containing tissue extracts and with regard to the role of SP as a possible neurotransmitter.
mesh_terms: D000818:Animals; D001921:Brain / Q000502:physiology; D002417:Cattle; D004386:Duodenum / Q000187:drug effects; D005260:Female; D007082:Ileum / Q000187:drug effects; D066298:In Vitro Techniques; D007422:Intestines / Q000502:physiology; D009619:Nociceptors / Q000187:drug effects*; D011453:Prostaglandins / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D013116:Spinal Cord / Q000502:physiology; D013373:Substance P / Q000032:analysis / Q000494:pharmacology*; D014020:Tissue Extracts; D014590:Uterine Contraction / Q000187:drug effects
chemical_list: D011453:Prostaglandins; D014020:Tissue Extracts; D013373:Substance P