S. Palmero et al., TRIIODOTHYRONINE DIRECTLY AFFECTS RAT SERTOLI-CELL PROLIFERATION AND DIFFERENTIATION, Journal of Endocrinology, 145(2), 1995, pp. 355-362
The addition of physiological concentrations II nM) of tri-iodothyroni
ne (T-3) to the culture medium of Sertoli cells from prepubertal (8-da
y-old) rats stimulated both protein synthesis (+55%) and lactate (+50%
) production, while it inhibited DNA synthesis (-30/35%) and aromatase
activity (-45/50%); insignificant T-3-dependent effects were observed
in cultured Sertoli cells from midpubertal (28-day-old) rats. These d
ata suggest an age-dependent role for thyroid hormone in promoting and
maintaining Sertoli cell differentiation at puberty; moreover, the ho
rmone is involved in the regulation of Sertoli cell proliferation. The
present study validates the role of Sertoli cells as a specific targe
t for T-3 action at the testis level; it also demonstrates the existen
ce of an early and critical direct influence of thyroid hormone on Ser
toli cell proliferation and functional maturation.