Fukunaga Y, Itoh H, Hosoda K, Doi K, Matsuda J, Son C, Yamashita J, Chun T H, Tanaka T, Inoue M, Masatsugu K, Saito T, Sawada N, Nakao K
Department of Medicine and Clinical Science, Kyoto University Graduate School of Medicine, Japan.
J Hypertens. 2000 Sep;18(9):1233-8. doi: 10.1097/00004872-200018090-00009.
Uncoupling proteins (UCPs) are the inner mitochondrial membrane-associated proteins, which dissipate the proton gradient and generate heat instead of ATP. The involvement of UCPs in energy expenditure and glucose metabolism has been suggested. Recently, we succeeded in cloning of rat UCP2 and UCP3.
The aim of this study was to elucidate the pathophysiological role of UCP2 and UCP3 in hypertension associated with hyperglycemia in stroke-prone spontaneously hypertensive rats (SHR-SP).
UCP2 and UCP3 mRNA levels of cardiac and gastrocnemius muscles in SHR-SP and Wistar-Kyoto (WKY) rats were determined at 6 weeks (prehypertensive stage) and at 15 weeks (hypertensive stage).
UCP2 and UCP3 mRNA levels in the heart of SHR-SP at 6 weeks were significantly higher than those of WKY rats (1.6-fold, 3.6-fold, respectively). These tendencies did not change in the heart at 15 weeks. UCP2 and UCP3 mRNA levels in the skeletal muscle of SHR-SP at 6 weeks were significantly higher than those of WKY rats (1.4-fold, 2.4-fold, respectively). In contrast, at 15 weeks, UCP2 and UCP3 mRNA levels in the skeletal muscle of SHR-SP were significantly lower than those of WKY rats (70 and 36% of WKY rats, respectively). Therefore, the decrease of UCP2 and UCP3 in the skeletal muscle was observed with the concomitant development of hypertension in SHR-SP. UCP2 mRNA levels in the epididymal fat of SHR-SP at 15 weeks were similar to that of WKY rats.
Altered gene expression of UCP2 and UCP3 might be related to some pathophysiological aspects in hypertension and glucose metabolism in SHR-SP.
解偶联蛋白（UCPs）是线粒体内膜相关蛋白，可消耗质子梯度并产生热量而非三磷酸腺苷（ATP）。已有研究表明UCPs参与能量消耗和葡萄糖代谢。最近，我们成功克隆了大鼠UCP2和UCP3。
本研究旨在阐明UCP2和UCP3在易卒中型自发性高血压大鼠（SHR-SP）中与高血糖相关的高血压的病理生理作用。
在6周龄（高血压前期）和15周龄（高血压期）时测定SHR-SP大鼠和Wistar-Kyoto（WKY）大鼠心脏和腓肠肌中UCP2和UCP3 mRNA水平。
6周龄时，SHR-SP大鼠心脏中的UCP2和UCP3 mRNA水平显著高于WKY大鼠（分别为1.6倍和3.6倍）。15周龄时，心脏中的这些趋势没有变化。6周龄时，SHR-SP大鼠骨骼肌中的UCP2和UCP3 mRNA水平显著高于WKY大鼠（分别为1.4倍和2.4倍）。相反，在15周龄时，SHR-SP大鼠骨骼肌中的UCP2和UCP3 mRNA水平显著低于WKY大鼠（分别为WKY大鼠的70%和36%）。因此，在SHR-SP大鼠中，随着高血压的发展，骨骼肌中UCP2和UCP3减少。15周龄时，SHR-SP大鼠附睾脂肪中的UCP2 mRNA水平与WKY大鼠相似。
UCP2和UCP3基因表达的改变可能与SHR-SP大鼠高血压和葡萄糖代谢的某些病理生理方面有关。
