Varga G, Papp M, Vizi E S
Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest.
Dig Dis Sci. 1990 Apr;35(4):501-7. doi: 10.1007/BF01536926.
While cholinergic nervous control of pancreatic enzyme secretion is well documented, data concerning adrenergic regulation of the exocrine pancreas are contradictory. In the present study we attempted to elucidate the direct action of adrenergic stimulation on pancreatic enzyme secretion. Rat pancreatic segments were set up in an organ bath and superfused with modified Krebs-Henseleit solution. Electrical field stimulation (EFS) stimulated amylase release from the segments. This stimulation was subject to inhibition with atropine up to 80%. Atropine-resistant enzyme discharge in response to EFS could be blocked by propranolol. Cholinergic agonist urecholine-induced amylase release was completely blocked by atropine. Noradrenaline (NA) exhibited a biphasic effect on amylase release. It inhibited the urecholine-induced amylase release in lower concentrations (10(-8)-10(-7) M), while it stimulated basal enzyme secretion in higher concentrations (10(-5)-10(-4) M). The inhibitory effect was mimicked by phenylephrine and completely prevented by prazosin. Isoprenaline concentration dependently enhanced, while clonidine and guanfacine did not affect amylase discharge. In conclusion, in rat pancreatic acinar tissue it seems likely that acetylcholine is the main neurotransmitter. Adrenergic action can be dual, inhibitory via alpha 1-adrenoceptors or stimulatory via beta-adrenoceptors on amylase secretion.
虽然胆碱能神经对胰腺酶分泌的控制已有充分记录，但有关肾上腺素能对外分泌胰腺调节的数据却相互矛盾。在本研究中，我们试图阐明肾上腺素能刺激对胰腺酶分泌的直接作用。将大鼠胰腺节段置于器官浴槽中，并用改良的克雷布斯 - 亨斯莱特溶液进行灌流。电场刺激（EFS）可刺激节段释放淀粉酶。这种刺激可被阿托品抑制达80%。普萘洛尔可阻断对EFS产生的阿托品抵抗性酶释放。胆碱能激动剂乌拉胆碱诱导的淀粉酶释放可被阿托品完全阻断。去甲肾上腺素（NA）对淀粉酶释放呈现双相作用。在较低浓度（10⁻⁸ - 10⁻⁷ M）时，它抑制乌拉胆碱诱导的淀粉酶释放，而在较高浓度（10⁻⁵ - 10⁻⁴ M）时，它刺激基础酶分泌。苯肾上腺素可模拟这种抑制作用，而哌唑嗪可完全阻止这种作用。异丙肾上腺素浓度依赖性增强淀粉酶释放，而可乐定和胍法辛则不影响淀粉酶释放。总之，在大鼠胰腺腺泡组织中，乙酰胆碱似乎是主要神经递质。肾上腺素能作用可能是双重的，通过α₁ - 肾上腺素受体起抑制作用，或通过β - 肾上腺素受体对淀粉酶分泌起刺激作用。
