Date of Award
University or Center
Clark Atlanta University(CAU)
Dr. David E. Potter
This study examined the ocular actions of an opioid agonist. Experiments were performed to evaluate the effects of DPDPE ([D-pen2, D-pen5] enkephalin), a delta opioid agonist on: 1) intraocular pressure (IOP) in rabbits; 2) cAMP accumulation in rabbit iris ciliary bodies (ICBs); 3) 3H-norepinephrine (NE) overflow from electrically stimulated sympathetic nerves in ICBs. DPDPE Lowerd IOP in normal rabbits but not in sympathectomized (SX) eyes. Naloxone did not inhibit the effect of DPDPE on IOP in normal rabbits. DPDPE inhibited 3H-NE overflow and suppressed cAMP accumulation in ICBs. The presence of naltrindole, a delta receptor antagonist, did not prevent the suppression of cAMP levels by DPDPE. Pertussis toxin (PTX) did not prevent the inhibition of cAMP levels by DPDPE. The data suggest that the lowering of IOP by DPDPE is mediated at both pre- (neuronal) and postjunctional (ciliary body) sites and may involve an atypical opioid receptor. In addition, the actions of DPDPE in the anterior segment may involve a PTXinsensitive G protein.
Wang, Duanran, "Opioid-induced ocular hypotension: actions at pre- and postjunctional sites" (1994). ETD Collection for AUC Robert W. Woodruff Library. 1002.