Inflammatory responses induced by substance P in rat paw.

摘要: Substance P (SP) injection in the plantar region of rat hind paw caused a dose related inflammation, which reached peak within 10 min and declined after 60 min. Low doses (0.25-0.063 mg/kg) SP-antagonists like (D-Pro2, D-Trp7,9)-SP D-Phe7, D-Trp9)-SP pretreatment significantly inhibited SP induced oedema, while higher (0.5-1 showed agonistic effects. Pretreatment with diphenhydramine alone or along low was highly significant blocking this latter combination being more effective than former. acute capsaicin produced synergestic effect on chronic oedema. The results indicate involvement histamine possible therapeutic importance mediated inflammatory type responses.