Uptake, turnover and release of norepinephrine in pigmented and albino rat eye.

The uptake, turnover and release of norepinephrine were studied in the rat eye as a function of its pigmentation. The endogenous norepinephrine level was increased in eyes with melanic pigments and the exogenous amine uptake was decreased. In the coloured eye, two sites for norepinephrine uptake and release were present. Desipramine did not inhibit in the same manner the amine in the albino and pigmented eye. No variation was found in the norepinephrine biosynthesis for the two races of rats. The release rate of exogenous amine was higher in the pigmented rat eye.