Effect of bremazocine, a kappa-opioid receptor agonist, on inositol phosphate formation in isolated iris-ciliary bodies.
The goal of the current study was to examine the effect of the kappa-opioid agonist, bremazocine (BRE), on inositol phosphate (IP) formation in the rabbit iris-ciliary body (ICB). Concentrations of BRE (10(-7) to 10(-5) M) augmented levels of IP. Incubation of ICBs with BRE (10(-6) M) produced a time-dependent increase in IP levels that peaked at 60 s and declined to basal levels by 5 min. The increase in IP levels produced by BRE (10(-6) M) was inhibited by the kappa-opioid receptor antagonist, nor-binaltorphimine (nor-BNI, 10(-7) to 10(-5) M) and by activation of PKC with PDBu (10(-7) M). These results demonstrate that kappa-opioid receptor activation by BRE in the rabbit ICB is linked to IP production. Thus, opioid agonist-induced increases in IP activity could play a role in BRE-induced increases in atrial natriuretic peptide release and alterations in aqueous humor dynamics.
Department of Pharmacology/Toxicology, Morehouse School of Medicine, Atlanta, Ga, USA. carnesj@msm.edu
Juanita
J
Dortch-Carnes
David E
DE
Potter
D000818:Animals; D001575:Benzomorphans / Q000494:pharmacology*; D002924:Ciliary Body / Q000187:drug effects* / Q000378:metabolism*; D066298:In Vitro Techniques; D007295:Inositol Phosphates / Q000096:biosynthesis*; D007498:Iris / Q000187:drug effects* / Q000378:metabolism*; D011817:Rabbits; D017473:Receptors, Opioid, kappa / Q000819:agonists* / Q000502:physiology
D001575:Benzomorphans; D007295:Inositol Phosphates; D017473:Receptors, Opioid, kappa; C027248:bremazocine