The specific inhibition of 11-cis-retinyl palmitate formation in the frog eye by diaminophenoxypentane, an inhibitor of rhodopsin regeneration.

The antischistosomal drug 1,5-di-(p-aminophenoxy) pentane (DAPP), an inhibitor of rhodopsin regeneration in the vertebrate retina, is shown to completely block the production of 11-cis-retinyl palmitate in the frog eye. An untreated frog generates a large amount of 11-cis-retinyl palmitate during 1-2 days in the dark after a strong bleach. Also, it is demonstrated that DAPP can deplete the stores of 11-cis-retinyl palmitate in the dark-adapted frog eye. The specificity of DAPP's inhibition of dark-adaptation is explored, and the usefulness of employing retinotoxic drugs to investigate the physiology and biochemistry of rhodopsin regeneration is discussed.