Abstract:

Different doses (low dose, 0.0245 g/kg bw; medium dose, 0.1225 g/kg bw; and high dose, 0.6125 g/kg bw) of an α-casein hydrolysate prepared by sequential enzymatic hydrolysis with pepsin followed by trypsin were orally administered to spontaneously hypertensive rats (SHRs), and the SHRs were tested for their systolic blood pressure (SBP) during 8 hours postadministration once a day for continuously 3 days in order to the anti-hypertension effect of single administration of theα-casein hydrolysate in SHRs. Moreover, in the continuous administration trial, high-dose administration was performed once at the time intervals of four hours twice a day and SBP measurement was done 2 hours after each administration. The results showed that in the single administration trial, normal Wistar rats administered high dose of theα-casein hydrolysate did not present any obvious change in SBP within 8 hours after administration. Each of the three doses had a notable inhibitory effect on the increase of SBP in SHRs. Among them, the antihypertensive effect of high dose was the best within the first 6 hours, and the SBP level of SHRs administered high dose for the longest period of time, reaching up to 6 hours, and the largest decrease by (29.50 ± 1.0) mmHg was observed at 5 hours. Furthermore, continuous administration of high dose could keep SBP at a lower level for a long time period.

Key words: hydrolysate derived fromα-casein, spontaneously hypertensive rat, systolic blood pressure