Ponery A S, Adeghate E
Department of Human Anatomy, Faculty of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666, Al Ain, United Arab Emirates.
Peptides. 2000 Oct;21(10):1503-9. doi: 10.1016/s0196-9781(00)00304-1.
Neuropeptides modulate the function of classic neurotransmitters in the regulation of body function. The role of neuropeptides in the regulation of endocrine secretion from the pancreas of diabetic rat is poorly understood. This study examined the pattern of distribution of neuropeptide-Y (NPY) and substance P (SP) in normal and diabetic rat pancreases. In addition to this, the effect of NPY and SP on glucagon secretion was also examined in the pancreases of normal and diabetic rats. Four weeks after the induction of diabetes, the pancreaseses of normal and diabetic rats were removed and processed for immunohistochemistry and glucagon secretion. The pattern of distribution of glucagon in the pancreas of diabetic rat was conspicuously deranged after the onset of diabetes. The pattern of distribution of NPY and SP was, however, similar in the pancreases of both normal and diabetic rats. Stimulation of normal rat pancreatic tissue with NPY (10(-12) and 10(-9) M) evoked large and significant (P < 0.001) increases in glucagon secretion compared to basal. In contrast to this, NPY inhibited glucagon secretion from the pancreas of diabetic rat. Treatment of pancreatic tissue fragments of normal rat with 10(-9) M SP resulted in significant (P < 0.03) increases in glucagon secretion. SP inhibited glucagon secretion from diabetic rat pancreas. In conclusion, NPY and SP stimulated glucagon secretion from the pancreas of normal rat. In contrast, NPY and SP inhibited glucagon secretion from diabetic rat pancreas.
神经肽在调节身体功能过程中可调节经典神经递质的功能。目前对神经肽在调节糖尿病大鼠胰腺内分泌分泌中的作用了解甚少。本研究检测了正常和糖尿病大鼠胰腺中神经肽Y（NPY）和P物质（SP）的分布模式。除此之外，还在正常和糖尿病大鼠的胰腺中检测了NPY和SP对胰高血糖素分泌的影响。糖尿病诱导四周后，切除正常和糖尿病大鼠的胰腺，进行免疫组织化学和胰高血糖素分泌检测。糖尿病大鼠发病后，其胰腺中胰高血糖素的分布模式明显紊乱。然而，正常和糖尿病大鼠胰腺中NPY和SP的分布模式相似。与基础水平相比，用NPY（10^(-12)和10^(-9) M）刺激正常大鼠胰腺组织可引起胰高血糖素分泌大幅显著增加（P < 0.001）。与此相反，NPY抑制糖尿病大鼠胰腺的胰高血糖素分泌。用10^(-9) M SP处理正常大鼠胰腺组织碎片可导致胰高血糖素分泌显著增加（P < 0.03）。SP抑制糖尿病大鼠胰腺的胰高血糖素分泌。总之，NPY和SP刺激正常大鼠胰腺的胰高血糖素分泌。相反，NPY和SP抑制糖尿病大鼠胰腺的胰高血糖素分泌。
