Modulation of Baroreflexes in Hypertensive Rats.
- Author:
Seok CHOI
1
;
Jai Hun KIM
;
Jae Myung SUN
;
Hee Wook WHI
;
Su Jin CHOI
;
Jae Yeoul JUN
;
Pyung Jin YOON
;
Jong Hoon CHUNG
;
Hyun Il KIM
;
Cheol Ho YEUM
Author Information
1. Department of Physiology, College of Medicine Chosun University, Gwangju, Korea. chyum@chosun.ac.kr
- Publication Type:Original Article
- Keywords:
Baroreflex;
Blood pressure;
Heart rate;
Hypertension
- MeSH:
Animals;
Arterial Pressure;
Baroreflex;
Blood Pressure;
Bradycardia;
Desoxycorticosterone;
Dihydrotachysterol;
Heart Rate;
Hypertension;
Infusions, Intravenous;
Nitroprusside;
Phenylephrine;
Rats;
Reflex;
Tachycardia
- From:Korean Journal of Nephrology
2009;28(6):545-551
- CountryRepublic of Korea
- Language:English
-
Abstract:
PURPOSE: Baroreceptor reflex regulation has been shown to reset towards a higher blood pressure level. This study was designed to assess alterations of chronotropic baroreflexes in two-kidney, one clip (2K1C) and deoxycorticosterone acetate (DOCA)-salt hypertensive rats. METHODS: Arterial pressure and heart rate (HR) were monitored continuously during intravenous infusions of phenylephrine or sodium nitroprusside. Ensuing reflex HR responses during each drug infusion were determined in two ways: (a) at 10 s intervals (time analysis), and (b) with every 10 mmHg change in pressure (pressure analysis). RESULTS: Both pressor and depressor responses produced by phenylephrine or sodium nitroprusside were comparable between normotensive and hypertensive rats. Both reflex tachycardia and bradycardia were attenuated in 2K1C hypertensive rats as compared with normotensive rats, whereas no significant differences were shown in DOCA-salt hypertensive rats. CONCLUSION: These results indicate that chronotropic baroreflexes are impaired in 2K1C hypertensive rats, but not in DOCA-salt hypertensive rats.
