Comparison of salt sensitivity of male and female F2 progeny from crosses between WKY and SHRSP rats.

Abstract

1. The present study compared the salt sensitivity of male and female F2 progeny obtained from crosses between Wistar-Kyoto/Izumo rats and stroke-prone spontaneously hypertensive rats (SHRSP A3b/Izm) after salt loading for 7 months. 2. Average systolic blood pressure in male F2 progeny was 10 mmHg higher than that of female F2 progeny at 5 months without salt loading. 3. The blood pressure in male F2 progeny was raised significantly 2 months after salt loading, but there was no further significant change in blood pressure even though salt loading was continued for 5 months. 4. In female F2 progeny, however, a significant change in systolic blood pressure was observed 1 month after salt loading and there was a further significant rise in blood pressure over 6 months. 5. Angiotensin I-converting enzyme and RR1023 loci were strongly linked to systolic and diastolic blood pressures in the male but not the female F2 progeny after salt loading for 7 months. 6. We therefore speculate that the hormonal difference between sexes might influence salt sensitivity in the SHRSP.