Theophylline abolishes the light peak in perfused cat eyes.
Theophylline, a phosphodiesterase inhibitor, was applied to the arterially perfused cat eye in vitro. At a concentration of 850 microM, theophylline abolished the light peak of the DC-ERG and led to a 20% increase in perfusate flow to the eye. The effects were reversible. An experimentally-induced increase in flow per se by 20% resulted in a slight enhancement of the light peak. The data suggest the involvement of cyclic nucleotides in the generation of the light peak. Theophylline also caused a decrease in the standing potential of the eye, an increase in the b-wave amplitude, and a decrease in the c-wave amplitude in a dose-dependent and reversible manner.
D000818:Animals; D002415:Cats; D000242:Cyclic AMP / Q000502:physiology; D004596:Electroretinography; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology*; D010775:Photic Stimulation; D010857:Pigment Epithelium of Eye / Q000187:drug effects*; D013806:Theophylline / Q000494:pharmacology*
D010726:Phosphodiesterase Inhibitors; D013806:Theophylline; D000242:Cyclic AMP