Determination of arterial baroreflex-blood pressure control in conscious rats.
OBJECTIVE
To study the determination of arterial baroreflex-blood pressure control (ABR-BP) in conscious rats.


METHODS
Blood pressure was continuously recorded with a computerized system in conscious freely moving rats. The principle of ABR-BP measurement is to compare the pressor response to a vasoactive drug (angiotensin II) before and after the interruption of this reflex.


RESULTS
(1) ABR-BP values revealed by angiotensin II were closely correlated with those by phenylephrine. Doses of angiotensin II did not influence the results within certain range. (2) ABR-BP was well correlated with arterial baroreflex-heart period control (ABR-HP). (3) Anesthesia inhibited ABR-BP. There existed a circadian variation of ABR-BP in WKY rats. (4) Blood pressure variability was closely related to ABR-BP, but not to ABR-HP. (5) ABR-BP was impaired in hypertensive rats.


CONCLUSIONS
ABR-BP is an important parameter to reflect the function of ABR. The present work makes it possible to determine ABR-BP in conscious rats. ABR-BP plays an important role in maintaining blood pressure stability and it is impaired in hypertension.
Su
Ding-Feng
DF
Department of Pharmacology, Basic Medical College, Second Military Medical University, Shanghai 200433, China. dfsu@citiz.net.
Chen
Li
L
Kong
Xian-Bo
XB
Cheng
Yong
Y
D000804:Angiotensin II / Q000494:pharmacology; D000818:Animals; D017704:Baroreflex / Q000187:drug effects / Q000502:physiology*; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006973:Hypertension / Q000503:physiopathology*; D008297:Male; D010656:Phenylephrine / Q000494:pharmacology; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D014662:Vasoconstrictor Agents / Q000494:pharmacology
D014662:Vasoconstrictor Agents; D000804:Angiotensin II; D010656:Phenylephrine