THYROID-HORMONE RECEPTOR-BETA MESSENGER-RNA EXPRESSION IN SERTOLI CELLS ISOLATED FROM PREPUBERTAL TESTIS

A polymerase chain reaction (PCR)-based assay was used to evaluate the expression of thyroid hormone receptor beta mRNA in Sertoli cells iso lated from both prepubertal rat and piglet testes. The expression of a n mRNA coding for the functional thyroid hormone receptor beta isoform , as established by the PCR assay, agrees with the presence of specifi c tri-iodothyronine (T-3) -binding sites in the Sertoli cell nuclei of both species, as previously evaluated by displacement analysis. The r esults ratify the existence of a functional T-3 receptor in the prepub ertal testis and confirm the Sertoli cell as a specific target for thy roid hormone action on the developing testis.