[Relation of HSP70 gene and spontaneously hypertension in rats]

The level of heat shock protein 70 messenger RNA was examined in aortic smooth muscle cells (ASMC) and hepatic tissue of Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR). The restriction fragment length polymorphism (RFLP) was also analysed in hepatic DNA. It was demonstrated that the basic level of heat shock protein 70 messenger RNA in ASMC and hepatic tissue of SHR were lower than that of the WKY rats. The extent of heat shock protein 70 messenger RNA accumulated in ASMC was higher in SHR than in WKY rats when the cells were heated by immersing the culture bottles in 42 degrees C water bath for 15 min and allowed to recover at 37 degrees C for 2 h. In contrast with WKY rats, the Bam HI restricted bepatic DNA showed that a fragment about 5.6 kb was lost in heat shock protein 70 gene from hepatic DNA of SHR. The results suggest that the ASMC of SHR is more sensitive to heat stress than that of WKY rats and the changes of heat shock protein gene sequence may be related to genetic hypertension.