Diametric effects of bacterial endotoxin lipopolysaccharide on adrenal and Leydig cell steroidogenic acute regulatory protein
| Autor: | Thorsten Diemer, Karen H. Hales, Maretha E. Roberts, Birinder K. Shankar, Dale B. Hales, Salil Ginde, H. Bruce Bosmann |
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| Rok vydání: | 2000 |
| Předmět: |
Lipopolysaccharides
Male endocrine system medicine.medical_specialty 3-Hydroxysteroid Dehydrogenases Lipopolysaccharide Biology chemistry.chemical_compound Mice Endocrinology Internal medicine Adrenal Glands medicine Escherichia coli Animals Northern blot Cholesterol Side-Chain Cleavage Enzyme RNA Messenger Testosterone Messenger RNA Leydig cell urogenital system Steroidogenic acute regulatory protein Cholesterol side-chain cleavage enzyme luteinizing hormone/choriogonadotropin receptor Leydig Cells Blotting Northern Phosphoproteins medicine.anatomical_structure chemistry Steroid 21-Hydroxylase |
| Zdroj: | Endocrinology. 141(11) |
| ISSN: | 0013-7227 |
| Popis: | Immune activation results in the activation of adrenal steroidogenesis and inhibition of gonadal steroidogenesis. Previous studies indicated that these effects were caused primarily by activation and suppression of the secretion of ACTH and LH, respectively. However, other evidence indicated a direct effect of the immune system on the gonads. In this study, serum testosterone, quantitated by RIA after lipopolysaccharide injection, showed a significant decrease within 2 h. Parallel measurement of serum LH showed no change. There were no differences in LH receptor or cAMP produced in Leydig cells between vehicle- and lipopolysaccharide-injected mice. The 30-kDa form of the steroidogenic acute regulatory (StAR) protein was quantitated, by Western blot, in Leydig cells and was found to decrease in a time-dependent manner. No change in StAR protein messenger RNA (mRNA) was detected by Northern analysis during this time, nor were any changes found in the levels of mRNA for the steroidogenic enzymes P450scc, 3β-hydroxysteroid dehydrogenaseΔ 4-Δ5-isomerase, or P450c17. In the adrenal, StAR protein was increased, as was StAR protein mRNA. No changes were observed in the levels of mRNA for P450scc, 3β-hydroxysteroid dehydrogenaseΔ 4-Δ5-isomerase, or P450c21. Thus, although the mechanisms of regulation differ, changes in the levels of StAR protein are a sensitive indicator of the steroidogenic capacity of these two tissues. |
| Databáze: | OpenAIRE |
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