Jensen B L, Rasch R, Nyengaard J R, Skott O
Department of Physiology, University of Odense, Winslowparken 19, DK-5000 Odense, Denmark.
Cell Tissue Res. 1997 May;288(2):399-406. doi: 10.1007/s004410050826.
The mutant beige mouse (C57BL/6 bg) has a disease characterised by abnormally enlarged cytoplasmic granules in a variety of cells. With the purpose of establishing a suitable cellular model for studying renin secretion, the present study was undertaken to compare renin granule morphology in beige mice with that of control (NMRI) mice. Immunohistochemistry with an antibody specific for renin revealed intense staining of the juxtaglomerular part of the afferent arterioles in both strains of mice. Plasma renin concentrations were higher in the controls than in the beige mice (4.4+/-0.6 vs 2.5+/-0.3 mGoldblatt units/ml). The total volume of renin granules per afferent arteriole was similar in the two mice strains (1114 microm3 in the controls and 1507 microm3 in the beige mice). The total number of renin granules per arteriole as assessed by stereological techniques was about 1900 in controls (average granular volume 0.681 microm3), whereas 1-2 large granules were present per cell in beige mice. The volume of afferent arteriole that contained secretory granules was lower in the beige mice. We conclude that the beige mouse synthesizes, stores and releases active renin. Renin secretory granules in beige mice are grossly enlarged with 1-2 granules per juxtaglomerular cell. Compared with control mice, a similar amount of total renin granule volume per afferent arteriole is contained in a smaller part of beige mouse afferent arteriole. Granular cells from beige mice could therefore be a valuable tool in the study of renin release.
突变的米色小鼠（C57BL/6 bg）患有一种疾病，其特征是多种细胞中的细胞质颗粒异常增大。为了建立一个适合研究肾素分泌的细胞模型，本研究旨在比较米色小鼠和对照（NMRI）小鼠的肾素颗粒形态。用肾素特异性抗体进行免疫组织化学分析显示，两种品系小鼠的入球小动脉近球旁部分均有强烈染色。对照小鼠的血浆肾素浓度高于米色小鼠（4.4±0.6 vs 2.5±0.3 mGoldblatt单位/毫升）。两条小鼠品系中每条入球小动脉的肾素颗粒总体积相似（对照小鼠为1114立方微米，米色小鼠为1507立方微米）。通过体视学技术评估，对照小鼠每条小动脉的肾素颗粒总数约为1900个（平均颗粒体积0.681立方微米），而米色小鼠每个细胞中有1 - 2个大颗粒。米色小鼠中含有分泌颗粒的入球小动脉体积较小。我们得出结论，米色小鼠能合成、储存和释放活性肾素。米色小鼠的肾素分泌颗粒明显增大，每个近球旁细胞有1 - 2个颗粒。与对照小鼠相比，米色小鼠入球小动脉中相同总量的肾素颗粒体积存在于较小的部分中。因此，米色小鼠的颗粒细胞可能是研究肾素释放的一个有价值的工具。
