Aerts L, Van Assche F A
Department of Obstetrics and Gynaecology, U.Z. Gasthuisberg, K.U. Leuven, Belgium.
Diabetes Res. 1991 Sep;18(1):1-10.
According to their general appearance, the ultrastructural morphology of their organelles and their functional status, B cells can be divided into dark, unresponsive B cells with condensed mitochondria and narrow RER-cisternae, and pale activated B cells with orthodox mitochondria and distended RER. In control rats, during a three hour glucose infusion experiment, there is a shift from a majority of dark B cells to a majority of pale B cells, and a decrease in the proportion of dark and mixed islets in favour of the pale islets. No degranulation however (dark and light granules) occurs. In adult youngsters of severely diabetic mothers, known to be hyperresponsive to glucose stimulation, a more important mass of pale activated B cells is present in basal conditions, and is not augmented by stimulation. Dark and mixed islets are scarce in these animals and some degranulation occurs. The data illustrate that in control and in hyperresponsive rats, the B cells manage very well, to meet the increasing demand of insulin without any signs of exhaustion or damage. The data confirm in vivo, and at the morphological level, the concepts of functional heterogeneity and of dose-dependent recruitment of pancreatic B cells. Moreover functional heterogeneity of islets is suggested.
根据B细胞的总体外观、细胞器的超微结构形态及其功能状态，可将其分为线粒体浓缩且粗面内质网池狭窄的暗型、无反应性B细胞，以及线粒体正常且粗面内质网扩张的亮型活化B细胞。在对照大鼠中，在三小时的葡萄糖输注实验期间，出现了从大多数暗型B细胞向大多数亮型B细胞的转变，并且暗型和混合型胰岛的比例下降，有利于亮型胰岛。然而，未发生脱颗粒现象（暗颗粒和亮颗粒）。在已知对葡萄糖刺激反应过度的重度糖尿病母亲的成年幼崽中，基础状态下存在更多数量的亮型活化B细胞，且刺激后并未增加。这些动物中的暗型和混合型胰岛稀少，并且发生了一些脱颗粒现象。数据表明，在对照大鼠和反应过度的大鼠中，B细胞能够很好地应对胰岛素需求的增加，而没有任何耗尽或损伤的迹象。这些数据在体内和形态学水平上证实了胰腺B细胞功能异质性和剂量依赖性募集的概念。此外，提示了胰岛的功能异质性。
