Effect of neonatal triiodothyronine (T3) treatment (hormonal imprinting) on the sexual behavior of adult rats.

Neonatal treatment with triiodothyronine increased the mounting and decreased the intromission of male rats. Number of inactive rats and number of ejaculations were not changed. In females a non-significant increase of Meyerson index was observed. Considering earlier results, the experiment demonstrates that neonatal T3 treatment can influence different receptors for life. The results also supports earlier observations on the sexual behavioral effect of perinatal treatment with molecules being structurally different from steroids however able to bind to receptors of the steroid receptor superfamily.