Effect of AT₁ receptor on changes of tyrosine hydroxylase-immunoreactivity in rostral ventrolateral medulla induced by brain cholinergic stimuli in rats / 浙江大学学报·医学版
Journal of Zhejiang University. Medical sciences
; (6): 71-77, 2011.
Article
in Chinese
| WPRIM (Western Pacific)
| ID: wpr-319830
Responsible library:
WPRO
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of AT₁ receptor on the changes of tyrosine hydroxylase-immunoreactivity (TH-IR) in rostral ventrolateral medulla (RVLM) induced by brain cholinergic stimuli in rats.</p><p><b>METHODS</b>Male SD rats were randomly divided into 4 groups NS + CBC group, Los + CBC group, Los + NS group and NS + NS group. AT₁ was blocked by pretreatment of 20 μg losartan in Los + CBC and Los + NS groups; intracerebroventricular injection of 0.5 μg carbachol was used for cholinergic stimuli in NS + CBC and Los + CBC groups; normal saline (NS) was used for control. The output amount of natrium in kidney, glomerular filtration rate (GFR) and renal plasma flow (PRF) were observed. The changes of TH-IR in the RVLM were observed by immunohistochemistry.</p><p><b>RESULT</b>In NS + CBC group carbachol induced potent natriuresis, after pretreatment of losartan the natriuretic effect was partially inhibited in Los + CBC group. Both the number and optical density of TH-IR positive neurons in NS + CBC group were markedly increased than those in NS + NS group (P < 0.05); while those in Los + CBC group were significantly lower than those in NS+CBC group (P < 0.05). Intracerebroventricular injection of carbachol and losartan had no effect on GFR and RPF(P > 0.05).</p><p><b>CONCLUSION</b>The results suggest that cholinergic stimuli can induce potent natriuresis and increase the activity of adrenergic neurons in the RVLM; the above effects can be down regulated by blockade of brain AT₁ receptor.</p>
Full text:
Available
Database:
WPRIM (Western Pacific)
Main subject:
Pharmacology
/
Physiology
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Tyrosine 3-Monooxygenase
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Carbachol
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Medulla Oblongata
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Random Allocation
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Rats, Sprague-Dawley
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Losartan
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Receptor, Angiotensin, Type 1
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Drug Antagonism
Limits:
Animals
Language:
Chinese
Journal:
Journal of Zhejiang University. Medical sciences
Year:
2011
Document type:
Article