Inhibition of Hypothalamic Thyrotropin-Releasing Hormone Messenger Ribonucleic Acid during Food Deprivation*
| Autor: | O. J. F. Foster, D. J. A. Eckland, N. G. Blake, Stafford L. Lightman |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
Male
endocrine system medicine.medical_specialty Pituitary gland endocrine system diseases Hypothalamus Thyrotropin Thyrotropin-releasing hormone In situ hybridization Biology Pituitary thyroid axis Endocrinology Anterior pituitary Internal medicine medicine Animals RNA Messenger Protein Precursors Thyrotropin-Releasing Hormone Triiodothyronine digestive oral and skin physiology Thyroid Rats Inbred Strains Prolactin Pyrrolidonecarboxylic Acid Rats medicine.anatomical_structure Food Deprivation hormones hormone substitutes and hormone antagonists |
| Zdroj: | Endocrinology. 129:2714-2718 |
| ISSN: | 1945-7170 0013-7227 |
| DOI: | 10.1210/endo-129-5-2714 |
| Popis: | Food deprivation in laboratory rats induces profound changes in the neuroendocrine system. We have investigated the hypothalamic and pituitary responses of the hypothalamo-pituitary thyroid axis to 48-h food deprivation in Sprague-Dawley rats. Peripheral T3 and hypophysial portal TRH were measured by RIA, and TSH beta, PRL, and pro-TRH mRNA were measured using in situ hybridization histochemistry. Peripheral total T3 was greatly reduced in food-deprived rats. Hypothalamic portal blood TRH levels declined significantly with time in control animals. The initial level of TRH in the portal blood of food-deprived rats was significantly reduced compared to that in controls, but did not fall further with time. In situ hybridization histochemistry revealed significantly lower pro-TRH mRNA in the paraventricular nucleus of food-deprived animals, while pro-TRH mRNA in the reticular nucleus remained unaltered. Furthermore, in the anterior pituitary, TSH beta mRNA decreased significantly in food-deprived animals, while PRL mRNA was unaltered. We conclude that the reduction in circulating T3 after food deprivation appears to be due primarily to decreased hypothalamic TRH synthesis and release. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|