Baroreceptor-heart rate reflex function before and after surgical reversal of two-kidney, one-clip hypertension in the rat. 1990

M E Edmunds, and G I Russell, and P R Burton, and J D Swales
Department of Medicine, University of Leicester, UK.

Baroreflex function was studied in conscious early phase (less than 6 weeks) two-kidney, one-clip hypertensive rats before and 24 hours after surgical reversal of hypertension by removal of the constricting renal artery clip or after pharmacological reduction of blood pressure by an infusion of hydralazine or captopril. A normotensive sham-clipped group was included. Another group of two-kidney, one-clip rats was studied 3 weeks after unclipping. Baroreflex sensitivity, as assessed by the steady-state method using a graded phenylephrine infusion, mean arterial pressure, and heart rate were measured preoperatively and at 24 hours postoperatively. Two-kidney, one-clip rats were significantly hypertensive preoperatively compared with control (mean arterial pressure, 183 +/- 4 vs. 106 +/- 2 mm Hg, p less than 0.001), heart rate was similar (420 +/- 9 vs. 401 +/- 9 beats/min, p greater than 0.05), and baroreflex sensitivity was significantly reduced (0.76 +/- 0.07 vs. 1.50 +/- 0.20 msec/mm Hg; p less than 0.001). There was a minimal change in heart rate despite the fall in mean arterial pressure in all hypertensive groups, indicating resetting of the baroreflexes. At 24 hours after the operation, baroreflex sensitivity was unchanged in all groups compared with the preoperative value. By 3 weeks, baroreflex sensitivity was significantly greater than in the hypertensive two-kidney, one-clip rats before the operation and 24 hours after they were unclipped, but not compared with normotensive sham-clipped rats. Thus, although resetting occurs within 24 hours, whatever the method of blood pressure reduction, baroreflex sensitivity remains impaired at this time.(ABSTRACT TRUNCATED AT 250 WORDS)

UI MeSH Term Description Entries
D006978 Hypertension, Renovascular Hypertension due to RENAL ARTERY OBSTRUCTION or compression. Hypertension, Goldblatt,Goldblatt Syndrome,Goldblatt Hypertension,Renovascular Hypertension,Syndrome, Goldblatt
D011311 Pressoreceptors Receptors in the vascular system, particularly the aorta and carotid sinus, which are sensitive to stretch of the vessel walls. Baroreceptors,Receptors, Stretch, Arterial,Receptors, Stretch, Vascular,Stretch Receptors, Arterial,Stretch Receptors, Vascular,Arterial Stretch Receptor,Arterial Stretch Receptors,Baroreceptor,Pressoreceptor,Receptor, Arterial Stretch,Receptor, Vascular Stretch,Receptors, Arterial Stretch,Receptors, Vascular Stretch,Stretch Receptor, Arterial,Stretch Receptor, Vascular,Vascular Stretch Receptor,Vascular Stretch Receptors
D011919 Rats, Inbred Strains Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding. August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D012018 Reflex An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.
D001794 Blood Pressure PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS. Systolic Pressure,Diastolic Pressure,Pulse Pressure,Pressure, Blood,Pressure, Diastolic,Pressure, Pulse,Pressure, Systolic,Pressures, Systolic
D002216 Captopril A potent and specific inhibitor of PEPTIDYL-DIPEPTIDASE A. It blocks the conversion of ANGIOTENSIN I to ANGIOTENSIN II, a vasoconstrictor and important regulator of arterial blood pressure. Captopril acts to suppress the RENIN-ANGIOTENSIN SYSTEM and inhibits pressure responses to exogenous angiotensin. (S)-1-(3-Mercapto-2-methyl-1-oxopropyl)-L-proline,Capoten,Lopirin,SQ-14,225,SQ-14,534,SQ-14225,SQ-14534,SQ 14,225,SQ 14,534,SQ 14225,SQ 14534,SQ14,225,SQ14,534,SQ14225,SQ14534
D005260 Female Females
D006339 Heart Rate The number of times the HEART VENTRICLES contract per unit of time, usually per minute. Cardiac Rate,Chronotropism, Cardiac,Heart Rate Control,Heartbeat,Pulse Rate,Cardiac Chronotropy,Cardiac Chronotropism,Cardiac Rates,Chronotropy, Cardiac,Control, Heart Rate,Heart Rates,Heartbeats,Pulse Rates,Rate Control, Heart,Rate, Cardiac,Rate, Heart,Rate, Pulse
D006830 Hydralazine A direct-acting vasodilator that is used as an antihypertensive agent. Hydrallazin,Apresoline,Apressin,Apressoline,Hydralazine Hydrochloride,Hydralazine mono-Hydrochloride,Hydrazinophthalazine,Nepresol,Hydralazine mono Hydrochloride,Hydrochloride, Hydralazine,mono-Hydrochloride, Hydralazine
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia

Related Publications

M E Edmunds, and G I Russell, and P R Burton, and J D Swales
December 1981, Clinical science (London, England : 1979),
M E Edmunds, and G I Russell, and P R Burton, and J D Swales
February 1984, The American journal of physiology,
M E Edmunds, and G I Russell, and P R Burton, and J D Swales
January 1980, Hypertension (Dallas, Tex. : 1979),
M E Edmunds, and G I Russell, and P R Burton, and J D Swales
October 1986, Journal of hypertension. Supplement : official journal of the International Society of Hypertension,
M E Edmunds, and G I Russell, and P R Burton, and J D Swales
December 1984, Journal of hypertension. Supplement : official journal of the International Society of Hypertension,
M E Edmunds, and G I Russell, and P R Burton, and J D Swales
August 1983, Journal of hypertension,
M E Edmunds, and G I Russell, and P R Burton, and J D Swales
December 1981, Clinical science (London, England : 1979),
M E Edmunds, and G I Russell, and P R Burton, and J D Swales
January 1990, Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas,
M E Edmunds, and G I Russell, and P R Burton, and J D Swales
January 1982, Hypertension (Dallas, Tex. : 1979),
M E Edmunds, and G I Russell, and P R Burton, and J D Swales
April 1997, Hypertension (Dallas, Tex. : 1979),
Copied contents to your clipboard!