Abstract
To investigate whether hyperprolactinemia directly affects rat testicular steroidogenesis, we examined the effects of prolactin (PRL) on microsomal 3β-hydroxysteroid dehydrogenase (3β-HSD), 17-hydroxylase (17-OH), 17,20-desmolase (17,20-D), 17-ketosteroid reductase (17-KSR) and aromatase enzyme activities. Adult hypophysectomized, gonadotropin-treated Fisher rats were rendered hyperprolactinemic by isografting pituitaries under the kidney capsule. The controls received skeletal muscle. All rats were sacrificed 7 days later and serum PRL was measured in each animal. PRL levels were 198 ± 14 ng/ml in the hyperprolactinemic rats and 4.3 ± 0.6 ng/ml in the controls (P<0.001). The testes were resected, pooled according to PRL levels, and microsomes were prepared from each pool. The activities of the 3β-HSD, 17-OH, 17,20-D, 17-KSR and aromatase were measured using as substrates 14C dehydroepiandrosterone, progesterone, 17-hydroxyprogesterone, androstenedione and testosterone, respectively. Hyperprolactinemia was associated with significant decreases in 3β-HSD, 17-OH, 17,20-D, 17-KSR and aromatase activities when compared to controls (P<0.005). We conclude that prolactin may have a direct effect on rat testicular steroidogenesis which appears to be independent of changes in gonadotropin secretion.
Original language | English (US) |
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Pages (from-to) | 47-48 |
Number of pages | 2 |
Journal | Hormone and Metabolic Research |
Volume | 17 |
Issue number | 1 |
DOIs | |
State | Published - 1985 |
Externally published | Yes |
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism
- Biochemistry
- Endocrinology
- Clinical Biochemistry
- Biochemistry, medical