Basic characteristics of experimental animals: body weight (A), systolic blood pressure (B), and heart rate (C). The data are presented as means ± SD. Statistical significance: * p < 0.05, ** p < 0.01, *** p < 0.001 between WKY and SHR at the same age (WKY-7 vs. SHR-7, WKY-20 vs. SHR-20 and WKY-52 vs. SHR-52), ++ p < 0.01, +++ p < 0.001 vs. 7-week group of the same phenotype (WKY-20 vs. WKY-7, SHR-20 vs. SHR-7, WKY-52 vs. WKY-7 and SHR-52 vs. SHR-7), X
p < 0.05, XXX
p < 0.001 vs. 20-week group of the same phenotype (WKY-52 vs. WKY-20 and SHR-52 vs. SHR-20). WKY—Wistar-Kyoto rats, SHR—Spontaneously hypertensive rats, bpm—beats per minute.