Bilateral renal denervation can prevent the development of stress-induced hypertension in the borderline hypertensive rat.
The borderline hypertensive rat (BHR) shows large blood pressure responses to either stress or a high salt diet. Since the renal nerves have been shown to play a role in several animal models of hypertension, the current study sought to determine the effect of bilateral renal denervation on the development of stress-induced hypertension in the BHR. BHR were deprived of renal nerves under ether anesthesia after either 5 or 11 weeks of daily 2-hour stress sessions. Additional BHR received sham surgery. Unstressed BHR, age-matched to stressed groups, received denervation or sham surgery. Following a 3 week recovery period, the protocol (stress or no stress) was continued for 10 additional weeks. Tail cuff systolic blood pressures were obtained weekly. BHR stressed for 5 weeks prior to denervation failed to develop hypertension in response to continued stress. Although BHR stressed for 11 weeks prior to denervation showed a temporary reduction in pressure following denervation, blood pressure returned to the hypertensive levels of sham-operated controls after several weeks. Thus, there may be a critical period during which the renal nerves are necessary for the expression of stress-induced hypertension in the BHR. These observations are discussed in relation to the effects of renal denervation on hypertension in various animal models.
Lawler
J E
JE
Physiology Program, University of Tennessee, Knoxville 37996.
Sanders
B J
BJ
Cox
R H
RH
Mitchell
V P
VP
Baer
P G
PG
D000818:Animals; D001794:Blood Pressure; D001795:Blood Pressure Determination / Q000379:methods; D003714:Denervation; D006824:Hybridization, Genetic; D006973:Hypertension / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D007668:Kidney / Q000294:innervation*; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011919:Rats, Inbred Strains / Q000502:physiology*; D011921:Rats, Inbred WKY; D013312:Stress, Physiological / Q000150:complications