Hypotensive Effects of Arginase Inhibition by L-Norvaline in Genetic Models of Normotensive and Hypertensive Rats

The main effect of arginase inhibition after administration of L-norvaline is a decrease in BP. At the same time, norvaline causes various side effects in normotensive and hypertensive animals. In our experiments, L-norvaline was administered intraperitoneally (30 mg/kg) for 7 days to normotensive WAG rats (Wistar Albino Glaxo) and hypertensive ISIAH rats (Inherited, Stress-Induced Arterial Hypertension). In ISIAH rats, BP decrease was accompanied by an increase in diuresis, while in WAG rats, diuresis remained unchanged or little changed. At the same time, hypertensive rats demonstrated an increase of catecholamine content in the adrenal glands, while in normotensive animals, it was decreased. The differences in the effects of norvaline can be associated with different mechanisms of BP maintenance in normotensive and hypertensive animals. Normally, BP is maintained by the regulatory influences of the nitric oxide system. In hypertension, this system is weakened, and the hypotensive effects are probably achieved via increased diuresis.

Automated summary

The main effect of arginase inhibition with L-norvaline is a decrease in blood pressure. However, L-norvaline also causes various side effects in normotensive and hypertensive animals. In our experiments, L-norvaline was administered intraperitoneally to normotensive WAG rats and hypertensive ISIAH rats for 7 days. In the hypertensive rats, the decrease in blood pressure was accompanied by an increase in diuresis, while in the normotensive rats, diuresis remained unchanged or slightly changed. Additionally, hypertensive rats showed an increase in catecholamine content in the adrenal glands, while normotensive animals showed a decrease. The differential effects of norvaline may be related to the different mechanisms of blood pressure regulation in normotensive and hypertensive animals, with increased diuresis potentially contributing to the hypotensive effects in hypertension.