Dual effect of [D-Pen(2), D-Pen(5)]enkephalin on ion transport in guinea pig colon.
Effects of the delta-opioid receptor ligand, [D-Pen(2), D-Pen(5)]enkephalin (DPDPE) on basal and endothelin-1-induced ion secretion in guinea pig colon were investigated. Muscle-stripped segments of guinea pig colon were mounted in Ussing flux chambers and changes in the short-circuit current (I(sc)) were monitored continuously. DPDPE significantly reduced baseline I(sc) at a low dose, 1 nM; however DPDPE increased I(sc) at 10 and 100 microM. Endothelin-1 stimulated ion secretion that was unaltered in tissues pretreated with DPDPE. In guinea pig colon, delta-opioid receptor activation evoked both a proabsorptive and prosecretory response.
Gauthier
C
C
Department of Pharmacology and Experimental Therapeutics, Louisiana State University Medical Center, New Orleans, LA 70112, USA.
Reddix
R
R
D000701:Analgesics, Opioid / Q000494:pharmacology*; D000818:Animals; D003106:Colon / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D004594:Electrophysiology; D019332:Endothelin-1 / Q000494:pharmacology; D020881:Enkephalin, D-Penicillamine (2,5)- / Q000494:pharmacology*; D006168:Guinea Pigs; D066298:In Vitro Techniques; D017136:Ion Transport / Q000187:drug effects; D008297:Male
D000701:Analgesics, Opioid; D019332:Endothelin-1; D020881:Enkephalin, D-Penicillamine (2,5)-