TY - JOUR
T1 - Increased expression of angiotensin-converting enzyme in retinas of diabetic rats
AU - Okada, Yuji
AU - Yamanaka, Ichiro
AU - Sakamoto, Taiji
AU - Hata, Yasuaki
AU - Sassa, Yukio
AU - Yoshikawa, Hiroshi
AU - Fujisawa, Kimihiko
AU - Ishibashi, Tatsuro
AU - Inomata, Hajime
N1 - Funding Information:
The authors thank Dr. Nobuaki Miyawaki for helpful suggestions. This study was supported by grants from the Ministry of Education, Science, Sports and Culture, Japan Grant-in-Aid for Scientific Research (A) (2) No. 09307040, (B) No. 09470382 and (B) No. 11470365, and the Health Sciences Research Grants, Japan.
PY - 2001
Y1 - 2001
N2 - Purpose: The aim of this study was to examine the localization and the changes in the amount of angiotensin-converting enzyme (ACE) and the relationship between the renin-angiotensin (RA) system and vascular endothelial growth factor (VEGF)/VEGF-receptor system in the retinas of diabetic rats. Methods: Immunohistochemical localization of ACE, VEGF, and VEGF-receptor fetal liver kinase-1 (Flk-1) was examined in cryosections of the retinas of streptozotocin-injected diabetic rats. A semi-quantitative comparison of diabetic rats with age-matched controls was also performed by counting the ACE- or Flk-1-positive vessels per microscopic field. Results: ACE immunoreactivity was localized in the retinal vessel walls, and the percentages of ACE-positive vessels were significantly increased in the retinas of diabetic rats maintained 3 to 5 months. Both VEGF and Flk-1 signals increased simultaneously with the increment of ACE immunoreactivity. Conclusions: ACE, expressed in the retinal vessel walls, increases simultaneously with the increment of both VEGF and Flk-1 in the retinas of diabetic rats, suggesting that upregulation of ACE might play some role in the progression of diabetic retinopathy through the VEGF/VEGF receptor system.
AB - Purpose: The aim of this study was to examine the localization and the changes in the amount of angiotensin-converting enzyme (ACE) and the relationship between the renin-angiotensin (RA) system and vascular endothelial growth factor (VEGF)/VEGF-receptor system in the retinas of diabetic rats. Methods: Immunohistochemical localization of ACE, VEGF, and VEGF-receptor fetal liver kinase-1 (Flk-1) was examined in cryosections of the retinas of streptozotocin-injected diabetic rats. A semi-quantitative comparison of diabetic rats with age-matched controls was also performed by counting the ACE- or Flk-1-positive vessels per microscopic field. Results: ACE immunoreactivity was localized in the retinal vessel walls, and the percentages of ACE-positive vessels were significantly increased in the retinas of diabetic rats maintained 3 to 5 months. Both VEGF and Flk-1 signals increased simultaneously with the increment of ACE immunoreactivity. Conclusions: ACE, expressed in the retinal vessel walls, increases simultaneously with the increment of both VEGF and Flk-1 in the retinas of diabetic rats, suggesting that upregulation of ACE might play some role in the progression of diabetic retinopathy through the VEGF/VEGF receptor system.
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U2 - 10.1016/S0021-5155(01)00412-9
DO - 10.1016/S0021-5155(01)00412-9
M3 - Article
C2 - 11754899
AN - SCOPUS:0035692498
SN - 0021-5155
VL - 45
SP - 585
EP - 591
JO - Japanese Journal of Ophthalmology
JF - Japanese Journal of Ophthalmology
IS - 6
ER -
