دورية أكاديمية
Effects of streptozotocin-induced diabetes and insulin treatment on the hypothalamic melanocortin system and muscle uncoupling protein 3 expression in rats.
| العنوان: | Effects of streptozotocin-induced diabetes and insulin treatment on the hypothalamic melanocortin system and muscle uncoupling protein 3 expression in rats. |
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| المؤلفون: | Havel, PJ, Hahn, TM, Sindelar, DK, Baskin, DG, Dallman, MF, Weigle, DS, Schwartz, MW |
| المصدر: | Diabetes, vol 49, iss 2 |
| بيانات النشر: | eScholarship, University of California |
| سنة النشر: | 2000 |
| المجموعة: | University of California: eScholarship |
| مصطلحات موضوعية: | Hypothalamus, Animals, Rats, Sprague-Dawley, Diabetes Mellitus, Experimental, Body Weight, Hormones, Insulin, Pro-Opiomelanocortin, Neuropeptide Y, Carrier Proteins, Ion Channels, Muscle Proteins, Receptors, Cell Surface, Mitochondrial Proteins, Eating, Male, Leptin, Uncoupling Protein 3, Diabetes, Obesity, Neurosciences, Nutrition, Autoimmune Disease, 2.1 Biological and endogenous factors, Metabolic and endocrine, Medical and Health Sciences, Endocrinology & Metabolism |
| جغرافية الموضوع: | 244 - 252 |
| الوصف: | Hypothalamic melanocortins are among several neuropeptides strongly implicated in the control of food intake. Agonists for melanocortin 4 (MC-4) receptors such as alpha-melanocyte-stimulating hormone (alpha-MSH), a product of proopiomelanocortin (POMC), reduce food intake, whereas hypothalamic agouti-related protein (AgRP) is a MC-4 receptor antagonist that increases food intake. To investigate whether reduced melanocortin signaling contributes to hyperphagia induced by uncontrolled diabetes, male Sprague-Dawley rats were studied 7 days after administration of streptozotocin (STZ) or vehicle. In addition, we wished to determine the effect of diabetes on muscle uncoupling protein 3 (UCP-3), a potential regulator of muscle energy metabolism. STZ diabetic rats were markedly hyperglycemic (31.3 +/- 1.0 mmol/l; P < 0.005) compared with nondiabetic controls (9.3 +/- 0.2 mmol/l). Insulin treatment partially corrected the hyperglycemia (18.8 +/- 2.5 mol/l; P < 0.005). Plasma leptin was markedly reduced in STZ diabetic rats (0.4 +/- 0.1 ng/ml; P < 0.005) compared with controls (3.0 +/- 0.4 ng/ml), an effect that was also partially reversed by insulin treatment (1.8 +/- 0.3 ng/ml). Untreated diabetic rats were hyperphagic, consuming 40% more food (48 +/- 1 g/day; P < 0.005) than controls (34 +/- 1 g/day). Hyperphagia was prevented by insulin treatment (32 +/- 2 g/day). In untreated diabetic rats, hypothalamic POMC mRNA expression (measured by in situ hybridization) was reduced by 80% (P < 0.005), whereas AgRP mRNA levels were increased by 60% (P < 0.01), suggesting a marked decrease of hypothalamic melanocortin signaling. The change in POMC, but not in AgRP, mRNA levels was partially reversed by insulin treatment. By comparison, the effects of diabetes to increase hypothalamic neuropeptide Y (NPY) expression and to decrease corticotropin-releasing hormone (CRH) expression were normalized by insulin treatment, whereas the expression of mRNA encoding the long form of the leptin receptor in the arcuate ... |
| نوع الوثيقة: | article in journal/newspaper |
| وصف الملف: | application/pdf |
| اللغة: | unknown |
| العلاقة: | qt25b4g57c; https://escholarship.org/uc/item/25b4g57cTest; https://escholarship.org/content/qt25b4g57c/qt25b4g57c.pdfTest |
| DOI: | 10.2337/diabetes.49.2.244 |
| الإتاحة: | https://doi.org/10.2337/diabetes.49.2.244Test https://escholarship.org/uc/item/25b4g57cTest https://escholarship.org/content/qt25b4g57c/qt25b4g57c.pdfTest |
| حقوق: | public |
| رقم الانضمام: | edsbas.CE357016 |
| قاعدة البيانات: | BASE |
| DOI: | 10.2337/diabetes.49.2.244 |
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