[The expression and significance of the angiopoietin-1 in the kidney of diabetic rats].
OBJECTIVE
To explore the expression and significance of angiopoietin-1 (Ang-1) in the renal tissue of diabetic rats.


METHODS
The SD rats were divided into the diabetic and control groups. The diabetic group was treated by streptozotocin. The expression of Ang-1 in renal tissue was detected by RT-PCR and immunohisochemistry at 2, 4, 8, 12, 16, 20 and 24 weeks. The level of Ang-1 was quantified by computer image analysis. The relationship between Ang-1 and the index of renal damage including renal/body weight, urinary protein excretion, glomerular volume, and glomerular area was analyzed.


RESULTS
Ang-1 mRNA in diabetic renal tissue was significantly upregulated at 4 and 8 weeks, compared with diabetic group at other time points or control group at the same time points, and then downregulated gradually after 12 weeks. The level of Ang-1 mRNA decreased significantly as compared with control group at 24 week. Ang-1 was outstandingly expressed in glomeruli. From 4-week to 24-week, the number of Ang-1 staining in diabetic glomeruli increased significantly as compared with control group, being maximal at 4 and 8 weeks, and subsequently decreased after 12 week. Ang-1 level was correlated with renal/body weight, glomerular volume, glomerular area, and urine protein excretion, respectively.


CONCLUSIONS
The change of Ang-1, which is early upregulation and late downregulation, exists in diabetic renal tissue. The unusual expression of Ang-1 is partly connected with the renal changes of diabetic rats.
Yang
Yi-bin
YB
Department of Nephrology, West China Hospital, Sichuan University, Chengdu 610041, China.
Chen
Ze-jun
ZJ
Liu
Fei
F
Huang
Song-min
SM
D042683:Angiopoietin-1 / Q000235:genetics* / Q000378:metabolism*; D000818:Animals; D001835:Body Weight; D003921:Diabetes Mellitus, Experimental / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D005786:Gene Expression Regulation; D007150:Immunohistochemistry; D007668:Kidney / Q000378:metabolism* / Q000473:pathology; D007678:Kidney Glomerulus / Q000378:metabolism / Q000473:pathology; D008297:Male; D009929:Organ Size; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D042683:Angiopoietin-1; D012333:RNA, Messenger