%0 Journal Article %A ZARRINDAST, MR %A REZAYAT, M %A ZOLFAGHARPOOR, MR %T EFFECTS OF CCK RECEPTOR AGONISTS AND ANTAGONISTS ON MORPHINE-INDUCED ANTINOCICEPTION IN MICE %J Medical Journal of the Islamic Republic Of Iran %V 14 %N 3 %U http://mjiri.iums.ac.ir/article-1-1652-en.html %R %D 2000 %K CCK agents, morphine, antinociception, mice, %X In the present study the effects of both CCK receptor agonists and antagonists on antinociception induced by morphine in the tail-flick test have been evaluated. M orphine induced dose-dependent antinociception in mice. The response of morphine was potentiated by sulfated cholecystokinin-8 (CCK-8S) but not by unsulfated cholecystokinin-8 (CCK-8U). The CCK receptor antagonists MK-329 and L-365, 260 decreased the potentiation of morphine antinociception induced by CCK-8S.•The antagonists even decreased the response induced by morphine in the pre5ence ofCCK-8U. High doses ofMK-329 and L-365, 260 also potentiated morphine's antinociception. Single administration of the CCK receptor agonists CCK-8 and CCK-8U or CCK receptor antagonists did not elicit any response in the tail-flick test. It is concluded that CCK receptor mechanisms are involved in the modulation of pain response and/or morphine antinociception. %> http://mjiri.iums.ac.ir/article-1-1652-en.pdf %P 261-266 %& 261 %! CCK and Morphine's Antinociception %9 Original Research: Basic Science in Medicine %L A-10-298-847 %+ From the Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Tehran, I.R. Iran. %G eng %@ 1016-1430 %[ 2000