Retinoid-Sensitive Steps in Steroidogenesis in Fetal and Neonatal Rat Testes: In Vitro and In Vivo Studies
| Autor: | Romain Lambrot, M. Lelievre-Pegorier, Gabriel Livera, J.M. Saez, Catherine Pairault, Virginie Rouiller-Fabre, René Habert |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Male
medicine.medical_specialty medicine.drug_class Retinoic acid Gestational Age Tretinoin Biology Rats Sprague-Dawley chemistry.chemical_compound Fetus Organ Culture Techniques Pregnancy In vivo Internal medicine Testis medicine Animals Testosterone RNA Messenger Retinoid Base Sequence Leydig cell Vitamin A Deficiency Retinol Leydig Cells Steroid 17-alpha-Hydroxylase Cell Differentiation DNA Cell Biology General Medicine Luteinizing Hormone Rats medicine.anatomical_structure Endocrinology Animals Newborn Reproductive Medicine chemistry Female Ex vivo |
| Zdroj: | Biology of Reproduction. 70:1814-1821 |
| ISSN: | 1529-7268 0006-3363 |
| DOI: | 10.1095/biolreprod.103.021451 |
| Popis: | Retinoic acid (RA) was recently shown to modify testosterone secretion of the fetal testis in vitro. We characterized this effect by culturing rat testes explanted at various ages, from Fetal Day 14.5 to Postnatal Day 3. In basal medium, RA inhibited, in a dose-dependent manner, both basal and acute LH-stimulated testosterone secretion by testes explanted on Fetal Days 14.5, 15.5, and 16.5. It had no effect on testes from older animals. The negative effect of RA did not result from a diminution in the number of Leydig cells but from a decrease in P450c17 mRNA levels and in LH-stimulated cAMP production. However, the RA-induced decrease in P450C17 mRNA levels was also observed with neonatal testes, suggesting that this enzymatic step is no longer rate limiting at this developmental stage. To study the physiological relevance of RA effects, we used fetuses and neonates issued from mothers fed a vitamin A-deficient (VAD) diet, resulting in a threefold decrease of plasma retinol concentration. On Fetal Day 18.5 and on Posnatal Day 3, testosterone secretion by the testis ex vivo was significantly increased in VAD animals. This shows that the endogenous retinol inhibits differentiation and/or function of fetal Leydig cells before Fetal Day 18.5 and is required for the normal regression of fetal Leydig cell function that occurs after Fetal Day 18.5. In conclusion, our results show that retinoids play a negative role on the steroidogenic activity during the differentiation of rat fetal Leydig cells. |
| Databáze: | OpenAIRE |
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