Objective: To investigate the association between insulin and hypertension.
Methods: Twenty spontaneously hypertension rats(SHR) and twenty Wistar-Kyoto rats(WKY) were randomly divided into two groups control group and insulin injection group. Systolic blood pressure(SBP),pulse rate(P), fasting blood sugar(FBS), fasting serum insulin(FINS) and insulin sensitivity index(ISI) were observed or calculated before and at the 60th day of the experiment.
Results: (SBP 165.5+/-5.8 compared with 108.2+/-4.7mmHg,P<0.01), P(405.8+/-19.6 compared with 336.6+/-9.6 /min P<0.01), FINS (6.89+/-0.99 compared with 5.78+/-0.91mU/L,P<0.05)of SHR were higher than those of WKY before experiment, but there was a lower ISI of SHR -3.397+/-0.191 compared with -3.085+/-0.132,P<0.01 . There were increases of SBP(210.0+/-8.5 compared with 184.3+/-8.0 mmHg,P<0.01),P(452.2+/-13.9 compared with 406.0+/-22.7/min P<0.01) and FINS (28.37+/-3.86 compared with 7.32+/-0.87 mU/L,P<0.01) in insulin injection group of SHR than those in controls,but ISI -4.119+/-0.260 compared with -3.604+/-0.174 P<0.01 decreased in insulin injection group; The same changes were observed in WKY rats after insulin injection (131.6+/-6.7 compared with 110.4+/-5.1 mmHg, 378.2+/-13.2 compared with 347.1+/-14.9/min 22.64+/-2.13 compared with 5.55+/-0.77 mU/L,-3.474+/-0.214 compared with 3.094+/-0.191 P<0.01 respectively).
Conclusion: Insulin resistance and hyperinsulinemia exist in SHR,chronic hyperinsulinemia may increase SBP and P,decrease ISI of WKY and SHR.