Effect of losartan, an angiotensin II type 1 receptor antagonist on cardiac autonomic functions of rats during acute and chronic inhibition of nitric oxide synthesis

Title:

Effect of losartan, an angiotensin II type 1 receptor antagonist on cardiac autonomic functions of rats during acute and chronic inhibition of nitric oxide synthesis

Creator:

Chaswal, M., Sakti Das, Prasad, J., Katyal, A., Mishra, A. K., and Fahim, M.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:596ad038-15de-494e-a6e4-3c743b576c2a
uuid:596ad038-15de-494e-a6e4-3c743b576c2a

Subject:

Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, losartan, L-NAME, angiotensin II, baroreflex sensitivity, heart rate variability, 14, and 612

Type:

article, články, model:article, and TEXT

Description:

We studied the effect of losartan on baroreflex sensitivity (BRS) and heart rate variability (HRV) of adult Wistar rats during acute and chronic inhibition of nitric oxide synthesis by NG -nitro-Larginine methyl ester (L-NAME). Chronic L-NAME administration (50 mg/kg per day for 7 days, orally through gavage) increased mean arterial pressure (MAP), heart rate but significantly decreased BRS. In addition, a significant fall of standard deviation of normal RR intervals, total spectral power, high frequency spectral power and a rise of low frequency to high frequency (LF: HF) ratio was seen. Acute L-NAME administration (30 mg/kg, i.v. bolus dose) also raised MAP and impaired HRV but it was associated with augmented BRS for bradycardia reflex. Losartan treatment (10 mg/kg, i.v.) in both acute and chronic L-NAME treated rats, decreased MAP but the difference was not significant. On the other hand, losartan administration normalized depressed BRS for bradycardia reflex and significantly reduced LF to HF ratio in chronic L-NAME treated rats. But this improvement was not observed in acute L-NAME group. These results indicate importance of mechanisms other than renin-angiotensin system in the pressor response of both acute as well as chronic L-NAME. However, autonomic dysregulation especially following chronic L-NAME appears to be partly angiotensin dependent., M. Chaswal ... [et al.]., and Obsahuje seznam literatury

Language:

English

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Source:

Physiological research | 2012 Volume:61 | Number:2

Harvested from:

CDK

Metadata only:

false