Is gender difference in postnatal thyroid growth associated with specific expression patterns of androgen and estrogen receptors?

Variations in sex steroids bioavailability were linked to the gender difference in the growth of thyroid glands of neonatal rats. In the present study we tested androgen receptor (AR) and estrogen receptor (ER) concentrations by ligand binding assay, and expression of their genes by RT-PCR and Western blot in the thyroid glands of neonatal rats. AR concentration remained elevated from postnatal day (PND) 10 onwards in males, whereas it decreased by PND 20 in females.

Mechanism underlying transient gestational-onset hypothyroidism-induced impairment of posttesticular sperm maturation in adult rats.

Objective: To understand the mechanism underlying gestational-onset hypothyroidism-induced male infertility.

Design: Controlled laboratory study.

Setting: Research laboratory in a university department of endocrinology.

Gestational and neonatal-onset hypothyroidism alters androgen receptor status in rat prostate glands at adulthood.

Background: Infertility associated with congenital and early childhood hypothyroidism is an important reproductive health problem in men. Nevertheless, the exact mechanism underlying hypothyroidism-induced changes in the prostate gland, an androgen-dependent organ that contributes a significant portion of the seminal plasma remains obscure. The present study tested the hypothesis "transient gestational- or neonatal-onset hypothyroidism may have duration dependent and lobe specific effect on androgen receptor (AR) status in the prostate glands of adult rats.