[The effects of losartan on pulmonary arterial collagen and AT1 in chronic hypoxic rats].
OBJECTIVE
To investigate the effects of losartan on pulmonary arterial collagen and AT1 in chronic hypoxic rats.


METHODS
Thirty male SD rats were randomly divided into three groups: control group, hypoxic group and therapeutic group. The animal model of pulmonary hypertension was established by exposing the rats to normabaric hypoxic conditions for three weeks. Then, the therapeutic group was given losartan for two weeks. We measured the expression of Collagen I, III and AT1 in arterioles by means of immunohistochemistry.


RESULTS
The positive degree of Collagen I in pulmonary arterioles in the hypoxic group was higher than that in the control group [(1.5202+/-0.069) vs (1.1324+/-0.071), P<0.01]; but in the therapeutic group it was lower than that in the hypoxic group [(1.1637+/-0.062) vs (1.5202+/-0.069), P<0.01]. There was no significant difference in collagen III and AT1 among the three groups (P>0.05).


CONCLUSIONS
Losartan could reduce pulmonary arterial collagen I expression, it may be one of the therapeutic mechanisms on hypoxic pulmonary hypertension of losartan.
Guan
Jian
J
Department of Respiratory Medicine, West China Hospital, Sichuan University, Chengdu 610041, China.
Cheng
De-yun
DY
Chen
Xiao-ju
XJ
Zhang
Yong
Y
Wang
Hui
H
Su
Qiao-li
QL
D047228:Angiotensin II Type 1 Receptor Blockers / Q000494:pharmacology; D000818:Animals; D002908:Chronic Disease; D003094:Collagen / Q000096:biosynthesis* / Q000235:genetics; D006976:Hypertension, Pulmonary / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D000860:Hypoxia / Q000150:complications / Q000378:metabolism*; D019808:Losartan / Q000494:pharmacology*; D008297:Male; D011651:Pulmonary Artery / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D044140:Receptor, Angiotensin, Type 1 / Q000096:biosynthesis* / Q000235:genetics
D047228:Angiotensin II Type 1 Receptor Blockers; D044140:Receptor, Angiotensin, Type 1; D003094:Collagen; D019808:Losartan