Effects of isofloxythepin enantiomers on prolactin secretion and postdecapitation convulsions in rats.

Racemic isofloxythepin and its enantiomers (0.05-1.0 mg/kg) administered subcutaneously increased serum prolactin levels in a dose-dependent manner in rats. The potencies of the drugs were equal for this variable. They (0.05-1.0 mg/kg, SC) also decreased dose-dependently the incidence and duration of postdecapitation convulsions, the convulsions being abolished at 1.0 mg/kg in all groups. Although (-)-enantiomer had slightly stronger effects than those of raceme and (+)-enantiomer, there were no great differences in their inhibitory effects on postdecapitation convulsions. The results indicate that isofloxythepin enantiomers in addition to raceme increase serum prolactin levels and inhibit postdecapitation convulsions and that they seem to have similar potency in blocking of dopamine receptors and alpha 1-adrenoceptors.