ISSN:
1573-6830
Keywords:
atrial natriuretic peptide receptors
;
angiotensin II receptors
;
cerebral capillaries
;
spontaneously hypertensive rats
;
blood-brain barrier
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Summary 1. We carried out investigations on specific atrial natriuretic peptide (ANP) and angiotensin II (ANG) binding sites in capillaries isolated from the cerebral cortex of spontaneously hypertensive rats (SHR), an animal model of human essential hypertension, and also from Wistar Kyoto rats (WKY). 2. In an equilibrium binding study done in the presence of increasing concentrations of the radiolabeled ligands, the binding of125I-ratα-ANP (1–28) [ANF-(99–126)] (125I-rANP) and125I-ANG (5-l-isoleucine) (125I-ANG) to the cerebral capillaries was single and of a high affinity. 3. The maximum binding capacity (B max) and dissociation constant (K d) in the125I-rANP binding of 20-week-old, hypertensive SHR was significantly lower than in age-matched, normotensive WKY. Conversely, a significant increase in theB max of125I-ANG binding of adult SHR was observed, with a significant decrease in theK d. 4. There was no differences in theB max of125I-rANP and125I-ANG binding between 4-week-old, prehypertensive SHR and age-matched WKY. However, there was a significant decrease in theK d of125I-rANP binding of SHR. 5. As a dramatic change in the binding kinetics of125I-rANP and125I-ANG was noted in the cerebral capillaries of adult sustained-hypertensive SHR, the possibility that ANP and ANG play a role in the etiology of dysfunction of the blood-brain barrier complicated with hypertension, by interacting with specific receptors, would have to be considered.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00713030
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