Temporal gene expression is restored concomitantly with germ cells in the experimentally regressed rat testis

Jacquetta M. Trasler, Acacia A. Alcivar, Caleb A. Awoniyi, Rosemary Santulli, Barry R. Zirkin, Norman B. Hecht

Research output: Contribution to journalArticlepeer-review

Abstract

The present study was designed to examine the effect of hypophy- sectomy and subsequent testosterone administration on germ cell num-bers and germ cell- and Sertoli cell-specific mRNA levels in adult rats. Rats were hypophysectomized and 4 weeks later received 24-cm testos-terone-containing polydimethylsiloxane (PDS) implants. Sham-hypo- physectomized rats received an empty PDS implant. At 0 and 3 days, and at 1, 2, 4, and 8 weeks, rats were killed. One testis from each rat (n = 4/group) was used to prepare total RNA; the other testis was used to enumerate stage VII-VIII germ cells. cDNA probes for germ cell and Sertoli cell products were used to monitor germ cell- and Sertoli cell- specific mRNAs on Northern blots. Four weeks after hypophysectomy (0 days), preleptotene and pachytene spermatocytes and round and elongating spermatids were reduced in number to 54%, 12%, 1%, and 0%, respectively, of the control values. Testosterone administration caused a time-dependent increase in germ cell numbers; after 8 weeks of testosterone treatment, preleptotene and pachytene spermatocytes and round and elongating spermatids were 75%, 79%, 74%, and 22%, respectively, of control values. Lactate dehydrogenase-C, phosphoglyc- erate kinase-2, protamine-1, and sulfated glycoprotein-2 mRNA levels (on a per μg RNA basis) were 34%, 34%, less than 1%, and 580% of control values, respectively, 4 weeks after hypophysectomy and 79%, 87%, 61%, and 192% of control values, respectively, after 8 weeks of testosterone treatment. Pachytene spermatocyte and round spermatid numbers increased, while Sertoli cell sulfated glycoprotein-2 mRNA levels decreased, with respect to 4 week hypophysectomy values, as early as 3 days after implantation of testosterone capsules. In contrast, germ cell (lactate dehydrogenase-C, phosphoglycerate kinase-2, and protamine-1) mRNA levels increased to the greatest extent between 1-4 weeks after the start of testosterone treatment and, after a short lag period, reflected increases in germ cell type and number. The results indicate that cell-specific mRNAs appear concomitantly with germ cell reappearance in a time-dependent manner in the testes of testosterone- treated hypophysectomized adult rats.

Original languageEnglish (US)
Pages (from-to)297-304
Number of pages8
JournalEndocrinology
Volume131
Issue number1
DOIs
StatePublished - Jul 1992

ASJC Scopus subject areas

  • Endocrinology

Fingerprint Dive into the research topics of 'Temporal gene expression is restored concomitantly with germ cells in the experimentally regressed rat testis'. Together they form a unique fingerprint.

Cite this