Neonatal Inhibition of Androgen Activity Alters the Programming of Body Weight and Orexinergic Peptides Differentially in Male and Female Rats

The study examined the effects of neonatal inhibition of androgen activity on body weight and orexinergic peptides in male and female rats. It found that blocking androgen receptors or testosterone metabolic pathways during the first five days of life led to a significant decrease in body weight in females by postnatal day 90, but not in males. Inhibition of aromatase reduced hypothalamic AgRP mRNA levels in males, while inhibition of 5α-reductase decreased hypothalamic AgRP and orexin mRNA levels in females. Both food intake and visceral fat were affected in both sexes depending on the inhibited testosterone pathway. These findings highlight the differential impact of androgens on energy metabolism and hypothalamic peptide systems during early development in male and female rats.