Bhandari Sunil, Watson Neil, Long Ervine, Sharpe Steve, Zhong Wenwen, Xu Shang-Zhong, Atkin Stephen L
Department of Renal Medicine, Hull Royal Infirmary, Hull and East Yorkshire Hospitals NHS Trust, Kingston-upon Hull, UK.
J Histochem Cytochem. 2008 Aug;56(8):733-43. doi: 10.1369/jhc.2008.950998. Epub 2008 Apr 28.
Somatostatin mediates inhibitory functions through five G protein-coupled somatostatin receptors (sst1-5). We used immunohistochemistry, immunofluorescence, and RT-PCR to determine the presence of somatostatin receptors sst1, sst2A, sst2B, sst3, sst4, and sst5 in normal and IgA nephropathy human kidney. All somatostatin receptors were detected in the thin tubules (distal convoluted tubules and loops of Henle) and thick tubules (proximal convoluted tubules) in the tissue sections from nephrectomy and biopsy samples. Immunopositive sst1 and sst4 staining was more condensed in the cytoplasm of tubular epithelial cells. In normal kidney tissue sections, podocytes and mesangial cells in the glomeruli stained for sst1, sst2B, sst4 and sst5, and stained weakly for sst3. In IgA kidney tissue, the expression of somatostatin receptors was significantly increased with particular immmunopositive staining for sst1, sst2B, sst4, and sst5 within glomeruli. In the epithelial cells, the staining for sst2B and sst4 in proximal tubules and sst1, sst2B, and sst5 in distal tubules was increased. The mRNA expression of sst1-5 was also detected by RT-PCR. Somatostatin and all five receptor subtypes were ubiquitously distributed in normal kidney and IgA nephropathy. The increased expression of somatostatin receptors in IgA nephropathy kidney might be the potential pathogenesis of inflammatory renal disease.
生长抑素通过五种G蛋白偶联生长抑素受体（sst1 - 5）介导抑制性功能。我们运用免疫组织化学、免疫荧光和逆转录聚合酶链反应（RT-PCR）来确定生长抑素受体sst1、sst2A、sst2B、sst3、sst4和sst5在正常人和IgA肾病患者肾脏中的存在情况。在肾切除术和活检样本的组织切片中，所有生长抑素受体均在细肾小管（远曲小管和髓袢）和粗肾小管（近曲小管）中被检测到。免疫阳性的sst1和sst4染色在肾小管上皮细胞的细胞质中更为密集。在正常肾脏组织切片中，肾小球中的足细胞和系膜细胞sst1、sst2B、sst4和sst5染色阳性，sst3染色弱阳性。在IgA肾病组织中，生长抑素受体的表达显著增加，肾小球内sst1、sst2B、sst4和sst5有特别明显的免疫阳性染色。在上皮细胞中，近端小管中sst2B和sst4以及远端小管中sst1、sst2B和sst5的染色增加。通过RT-PCR也检测到了sst1 - 5的mRNA表达。生长抑素和所有五种受体亚型在正常肾脏和IgA肾病中均广泛分布。IgA肾病肾脏中生长抑素受体表达的增加可能是炎症性肾脏疾病的潜在发病机制。
