Sex-specific concentrations of plasma proteins in rats determined by sex hormones in perinatal life.

The present investigation examined the relationship between concentrations of plasma proteins in oestrogen-primed adult rats and sex hormone concentrations in neonatal life. alpha 2-acute phase globulin (alpha 2-AP) and female specific protein (FP) were found to be higher in adult females than in adult males. Androgen administration in females on the first day of life declined permanently these protein concentrations, while neonatal castration in males on the first or third day of life resulted in a permanent increase in FP concentration. Both the alpha 2-AP and FP response in adulthood to hormonal stimulation is dependent on the androgen level during a critical neonatal organization period.