Yokota S, Oda T
Histochemistry. 1985;83(1):81-5. doi: 10.1007/BF00495305.
The light- and electron-microscopic localization of serine: pyruvate aminotransferase (SPT) in rat kidney was studied using immunoenzyme and protein A-gold techniques. Rat kidneys were fixed by perfusion through the abdominal aorta and small tissue slices were embedded in Epon, Lowicryl K4M, or LR Gold. The Epon was removed from the semithin sections, which were then stained using the immunoenzyme technique. Ultrathin sections of Lowicryl K4M- or LR gold-embedded materials were labeled using the protein A-gold technique. At light microscopy, discrete granular reaction deposits were exclusively present in the proximal tubule, all of whose segments were positive for SPT. A weakly positive reaction was observed in the distal tubules. At electron microscopy, gold particles indicating the antigenic sites for SPT were confined to the peroxisomes and mitochondria. The labeling intensity of both organelles was dependent on the embedding resins used. The labeling of Lowicryl K4M-embedded material was weaker than that of LR gold-embedded material; Quantitative analysis confirmed this result. Our results indicate that, in rat kidney, the main intracellular sites for SPT are peroxisomes and mitochondria of the proximal tubule.
利用免疫酶和蛋白A-金技术研究了大鼠肾脏中丝氨酸：丙酮酸转氨酶（SPT）的光镜和电镜定位。通过腹主动脉灌注固定大鼠肾脏，将小组织切片包埋在环氧树脂、低熔点树脂K4M或LR Gold中。从半薄切片中去除环氧树脂，然后用免疫酶技术染色。用蛋白A-金技术标记低熔点树脂K4M或LR Gold包埋材料的超薄切片。在光学显微镜下，离散的颗粒状反应沉积物仅存在于近端小管中，其所有节段的SPT均呈阳性。在远端小管中观察到弱阳性反应。在电子显微镜下，指示SPT抗原位点的金颗粒局限于过氧化物酶体和线粒体。两种细胞器的标记强度取决于所用的包埋树脂。低熔点树脂K4M包埋材料的标记比LR Gold包埋材料弱；定量分析证实了这一结果。我们的结果表明，在大鼠肾脏中，SPT的主要细胞内位点是近端小管的过氧化物酶体和线粒体。
