[Effects of captopril and losartan on expression of kidney aquaporin-2 mRNA and urine aquaporin-2 excretion in rats].
OBJECTIVE
To investigate effects of captopril and losartan on the expression of kidney aquaporin-2 (AQP2) mRNA and the excretion of urine AQP2 in rats.


METHODS
Thirty healthy rats were randomized into 3 groups, namely the control group, captopril group and losartan group, respectively. Blood and urine samples were collected from the rats for detecting serum Na(+), urine volume and urine osmolality in the course of medication. Urine AQP2 concentration was measured by enzyme-linked immunosorbent assay (ELISA). Semi-quantitative RT-PCR was performed for measurement of kidney inner medullary AQP2 and vasopressin V(2) receptor mRNA.


RESULTS
Urine volume was increased in rats of captopril and losartan groups as compared with that of the control group. However, urine osmolality was lower in captopril group than in the other two groups (P<0.05). RT-PCR revealed decreased quantity of the inner medullary AQP2 mRNA of the captopril group than that of the other two groups, but the quantity of V(2) receptor mRNA did not differ significantly between the 3 groups. Urine AQP2 concentration was significantly higher in captopril group than in the control (P<0.05) and losartan groups (P0<0.01).


CONCLUSIONS
Captopril can reduce the expression of the kidney inner medullary AQP2 mRNA and accelerate the excretion of the urine AQP2 in normal rats.
Jiang
Rong-Yan
RY
Department of Cardiovascular Diseases, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China. jiangsh@fimmu.com
Xu
Ding-Li
DL
Lai
Wen-Yan
WY
Ren
Hao
H
Shen
Qian-Bo
QB
Shao
Ya-Hui
YH
D047228:Angiotensin II Type 1 Receptor Blockers / Q000494:pharmacology; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology; D000818:Animals; D051399:Aquaporin 2 / Q000096:biosynthesis* / Q000235:genetics / Q000652:urine*; D002216:Captopril / Q000494:pharmacology*; D007668:Kidney / Q000378:metabolism*; D019808:Losartan / Q000494:pharmacology*; D008297:Male; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley
D047228:Angiotensin II Type 1 Receptor Blockers; D000806:Angiotensin-Converting Enzyme Inhibitors; D051399:Aquaporin 2; D012333:RNA, Messenger; D002216:Captopril; D019808:Losartan