3H-imipramine binding in human platelets: a study in normal twins

3H-imipramine binding was determined in freshly prepared intact platelets from 17 monozygotic (MZ) and 15 dizygotic (DZ) twin pairs, all of them male, adult, drug-free, and healthy volunteers. Sixteen males served as controls for determination of intraindividual variation of binding parameters. Both MZ and DZ twin pairs exhibited high intraclass correlations of Bmax values, but DZ twins were nearly as similar as MZ pairs. Interindividual variation of binding parameters is not large enough to reveal a significant genetic control.