Reversibility of baroreceptor hyposensitivity during reversal of hypertension.
Hypertension
; 15(6 Pt 2): 791-6, 1990 Jun.
Article
em En
| MEDLINE
| ID: mdl-2351432
The extent and characteristics of reversal of baroreceptor resetting after pressure normalization were studied in rats with renal hypertension of 2 months' duration. During the control period, the displacement of the entire baroreceptor function curve was accompanied by a decrease slope, indicating that the gain sensitivity was depressed by 36% in the renal hypertensive rats. In response to changes of +10 and -10 mm Hg in the control pressure, the gain sensitivity was attenuated by 56% and 42%, respectively. Two minutes after unclipping and bleeding when necessary, mean arterial pressure decreased from 171 +/- 11 to 134 +/- 11 mm Hg and remained at approximately the same level for the 2-hour period of observation. The extent of reversal of the mean pressure threshold for activation of the baroreceptors was approximately constant (approximately 60%) in the time range of 2-120 minutes. The extent of reversal was slightly higher when the changes in systolic pressure threshold divided by the total change in control diastolic pressure were calculated (maximal of 83%). During the first 20 minutes, the displacements of the curves were parallel with no change in the depressed gain sensitivity. Complete normalization of gain sensitivity was observed after 90-120 minutes. The data indicate that, within the first 2 hours of pressure normalization of chronic renal hypertensive rats, 1) reversal of the resetting of pressure threshold is pronounced (60-80%) but still incomplete and 2) gain sensitivity returns completely to normal.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Pressorreceptores
/
Hipertensão Renal
Limite:
Animals
Idioma:
En
Revista:
Hypertension
Ano de publicação:
1990
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Estados Unidos