Transfected rat mu opioid receptors (rMOR1 and rMOR1B) stimulate phospholipase C and Ca2+ mobilization.
The mu opioid agonist DAMGO increases intracellular Ca2+ concentration and inositol triphosphate formation in Chinese hamster ovary cells stably expressing the mu opioid receptors rMOR1 and rMOR1B, a recently isolated isoform of rMOR1. The increase in intracellular Ca2+ concentration is due solely to mobilization from internal stores. Both the DAMGO-induced stimulation of inositol triphosphate and increase in intracellular Ca2+ concentration is similar for both variants with an EC50 of about 1 microM, which is about an order of magnitude less efficient than the inhibition of adenylyl cyclase (EC50 = 150 microM).
Zimprich
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A
Department of Physiology, University of Munich, Germany.
Simon
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T
Höllt
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V
D000067956:Adenylyl Cyclase Inhibitors; D000818:Animals; D016466:CHO Cells; D002118:Calcium / Q000378:metabolism*; D006224:Cricetinae; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D004745:Enkephalins / Q000494:pharmacology*; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D051381:Rats; D017450:Receptors, Opioid, mu / Q000819:agonists*; D014162:Transfection; D010738:Type C Phospholipases / Q000378:metabolism*
D000067956:Adenylyl Cyclase Inhibitors; D004745:Enkephalins; D017450:Receptors, Opioid, mu; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D015544:Inositol 1,4,5-Trisphosphate; D010738:Type C Phospholipases; D002118:Calcium