Differential effects of selective endothelin type a receptor antagonist on the gene expression of vascular endothelial growth factor and its receptors in streptozotocin-induced diabetic heart.
Cardiovascular complications are an important feature of diabetes mellitus (DM). Abnormal and decreased coronary collateral development has been implicated in the pathogenesis of cardiac complications in DM. More recently, decreased expression of vascular endothelial growth factor (VEGF) and its receptors has been found in diabetic heart. To our knowledge, no study has focused on the therapeutic improvement associated with VEGF in diabetic heart. DM was induced by intraperitoneal injection of streptozotocin (65 mg/kg) in Sprague-Dawley rats, while control rats received only citrate buffer. After 1 week, the streptozotocin-treated rats were randomly divided into two groups: one group received the selective endothelin (ET) type A receptor antagonist TA-0201 at a dose of 1 mg/kg/day for 2 weeks by osmotic mini-pump, and the vehicle group received saline only. The plasma glucose level was 504 +/- 75 mg/dl in the diabetic rats and was unchanged by treatment with ET antagonist. The body weight was decreased in the diabetic rats compared with the control rats, but the left ventricular (LV)-body weight ratio was increased in the diabetic group and was unaffected by treatment with ET antagonist. mRNA expression of VEGF and its receptors (Flt-1 and Flk-1) in the LV tissues was assessed using real-time polymerase chain reaction. VEGF expression was significantly decreased in diabetic heart and was greatly improved by treatment with ET antagonist. The expression of VEGF receptors was down-regulated in early diabetic heart but was not recovered by treatment with ET antagonist. ET and its receptor A might have differential regulation on the gene expressions of VEGF and its receptors in early diabetic heart.
Jesmin
Subrina
S
Department of Cardiovascular Medicine, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan.
Zaedi
Sohel
S
Yamaguchi
Naoto
N
Maeda
Seiji
S
Shimojo
Nobutake
N
Masuzawa
Koichi
K
Yamaguchi
Iwao
I
Goto
Katsutoshi
K
Miyauchi
Takashi
T
D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001835:Body Weight; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D065130:Endothelin A Receptor Antagonists; D008297:Male; D011743:Pyrimidines / Q000627:therapeutic use*; D012333:RNA, Messenger; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D040262:Receptors, Vascular Endothelial Growth Factor / Q000235:genetics / Q000378:metabolism*; D013449:Sulfonamides / Q000627:therapeutic use*; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism*
D001786:Blood Glucose; D065130:Endothelin A Receptor Antagonists; D011743:Pyrimidines; D012333:RNA, Messenger; D013449:Sulfonamides; C113972:T 0201; D042461:Vascular Endothelial Growth Factor A; D040262:Receptors, Vascular Endothelial Growth Factor