AT1 receptor subtype mediates the inhibitory effect of central angiotensin II on cerebrospinal fluid formation in the rat.
Regul Pept
; 53(2): 123-9, 1994 Sep 22.
Article
em En
| MEDLINE
| ID: mdl-7831501
ABSTRACT
The effect of central administration of angiotensin II (AII) on cerebrospinal fluid (CSF) formation was studied in pentobarbital-anesthetized, artificially-ventilated rats. CSF production was measured by the ventriculocisternal perfusion method with Blue Dextran 2000 as the indicator. Baseline value of CSF production was 3.35 +/- 0.08 microliters/min. Intracerebroventricular (i.c.v.) infusion of AII at rates of 0.5 and 5 pg/min significantly lowered (P < 0.01) CSF formation by 23% and 16%, respectively. In comparison, high peptide doses (50 and 500 pg/min) did not alter this parameter. The inhibitory effect of low AII doses on CSF formation was blocked by the i.c.v. AT1 receptor subtype antagonists, losartan and SK&F 108566 (2.4 and 2.7 ng/min, respectively), but not by the AT2 receptor subtype-specific agent, PD 123319 (3.8 ng/min). Peptide AII antagonists, [Sar1,Ile8]AII (5 ng/min), which binds to both AT1 and AT2 receptors, had a similar effect to those of AT1-specific blockers. It is concluded that AII, by controlling CSF formation, may influence the water and electrolyte balance in the brain.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Angiotensina II
/
Receptores de Angiotensina
/
Líquido Cefalorraquidiano
Limite:
Animals
Idioma:
En
Revista:
Regul Pept
Ano de publicação:
1994
Tipo de documento:
Article