EARLY POSTNATAL TREATMENT WITH TRANSFORMING-GROWTH-FACTOR-ALPHA DOES NOT ALTER NONREPRODUCTIVE BEHAVIOR

Estrogen acting during the critical developmental period has been post ulated to defeminize and possibly masculinize male sexual behavior. Tr ansforming growth factor alpha (TGF alpha) also may be involved, becau se this growth factor, at least partly, mediates the mitotic effects o f estrogen on target tissues. Male transgenic mice overexpressing TGF alpha have elevated serum estradiol (E2) levels and they exhibit femin ization of many nonreproductive actions, suggesting that either TGF al pha and/or E2, or both, participate in the control of some nonreproduc tive behavior. Male and female CD-1 mice were treated with 4 mu g of r ecombinant human TGF alpha or 2-4 mu g E2 during the first 3 days of l ife. Although early TGF alpha treatment accelerates physical developme nt and influences the growth of the uterus and mammary gland, it faile d to have any effect on behavior, either in male or female mice. Early E2 treatment significantly lengthened immobility time in the swim tes t and reduced voluntary alcohol intake among the male mice. No changes in locomotor activity or aggressive behavior were noted. The expressi on of TGF alpha mRNA in the brainstem of adult male mice was not alter ed following neonatal TGF alpha or E2 treatment. However, neonatal exp osure to TGF alpha caused a moderate elevation in TGF alpha mRNA expre ssion in the female brainstem. Our results indicate that in male, but not in female mice, an excess of E2 during early life affects some non reproductive behavior. Furthermore, early treatment with recombinant h uman TGF alpha does not alter nonreproductive behavior in mice. (C) 19 97 Elsevier Science Inc.