Chun S J, Niijima A, Shimizu K, Nagai K
Division of Protein Metabolism, Osaka University, Japan.
Neurosci Lett. 1995 Dec 15;201(3):191-4. doi: 10.1016/0304-3940(95)12166-8.
Previous studies have indicated that neurons containing a vasoactive intestinal polypeptide (VIP)-like immunoreactive substance (VIP neurons) in the suprachiasmatic nucleus (SCN) are involved in regulating glucose metabolism in rats. In this connection, it has been suggested that in rats, VIP neurons in the SCN have neurotensin (NT) receptors. To clarify the role of NT, we examined the effects of intracranial injection of NT and an NT-antagonist on the hyperglycemic response to intracranial injection of 2-deoxy-D-glucose (2DG) in rats. The hyperglycemic and hyperglucagonemic responses caused by intracerebroventricular injection of 2DG were significantly enhanced by intracerebroventricular co-injection of NT, but suppressed by co-injection of the NT-antagonist. Intraperitoneal injection of the NT-antagonist did not affect the hyperglycemic and hyperglucagonemic responses to 2DG. These results suggest that intracranial NT plays an endogenously enhancive role in the hyperglycemic and hyperglucagonemic responses caused by 2DG.
先前的研究表明，视交叉上核（SCN）中含有血管活性肠肽（VIP）样免疫反应物质的神经元（VIP神经元）参与调节大鼠的葡萄糖代谢。就此而言，有人提出在大鼠中，SCN中的VIP神经元具有神经降压素（NT）受体。为了阐明NT的作用，我们研究了颅内注射NT和NT拮抗剂对大鼠颅内注射2-脱氧-D-葡萄糖（2DG）所致高血糖反应的影响。脑室注射2DG引起的高血糖和高胰高血糖素反应，在脑室联合注射NT时显著增强，但在联合注射NT拮抗剂时受到抑制。腹腔注射NT拮抗剂对2DG引起的高血糖和高胰高血糖素反应没有影响。这些结果表明，颅内NT在2DG引起的高血糖和高胰高血糖素反应中起内源性增强作用。
