O'Konski M S, Pandol S J
Department of Medicine, Veterans Administration Medical Center, San Diego, California 92161.
J Clin Invest. 1990 Nov;86(5):1649-57. doi: 10.1172/JCI114887.
In this study experiments were performed to correlate the rate of digestive enzyme secretion to morphologic observations of the apical cytoskeleton using dispersed rat pancreatic acini with various concentrations of caerulein. Caerulein at concentrations of 10 pM to 0.1 nM stimulated increasing rates of secretion of amylase, a digestive enzyme. Greater concentrations of caerulein caused progressively less amylase secretion. Transmission electron microscopy demonstrated several characteristics of the apical cytoskeleton in untreated acini that were altered with the "inhibitory" concentrations of caerulein. In control acini and acini stimulated with concentrations of caerulein up to 0.1 nM, the micrographs reveal an apical actin network extending into microvilli, an intermediate filament band, and electron-dense structures contained in both the actin filament network and the intermediate filament band. With concentrations of caerulein greater than 0.1 nM, these structures were progressively ablated. The findings with respect to the actin filament network were confirmed with light microscopic observations of dispersed acini stained with rhodamine-phalloidin. These results indicate that caerulein has marked morphologic effects on the pancreatic acinar cell cytoskeleton and that the cytoskeletal changes may modulate the secretory response.
在本研究中，利用不同浓度的蛙皮素处理分散的大鼠胰腺腺泡，进行实验以关联消化酶分泌速率与顶端细胞骨架的形态学观察结果。浓度为10 pM至0.1 nM的蛙皮素刺激淀粉酶（一种消化酶）的分泌速率不断增加。更高浓度的蛙皮素导致淀粉酶分泌逐渐减少。透射电子显微镜显示，未处理的腺泡中顶端细胞骨架的几个特征在蛙皮素的“抑制性”浓度下发生了改变。在对照腺泡和用高达0.1 nM浓度的蛙皮素刺激的腺泡中，显微照片显示顶端肌动蛋白网络延伸至微绒毛、一条中间丝带以及包含在肌动蛋白丝网络和中间丝带中的电子致密结构。当蛙皮素浓度大于0.1 nM时，这些结构逐渐消失。用罗丹明 - 鬼笔环肽染色的分散腺泡的光学显微镜观察结果证实了关于肌动蛋白丝网络的发现。这些结果表明，蛙皮素对胰腺腺泡细胞骨架具有显著的形态学影响，并且细胞骨架的变化可能调节分泌反应。
