Increased expression of intercellular adhesion molecule-1, vascular cellular adhesion molecule-1 and leukocyte common antigen in diabetic rat retina.
OBJECTIVE
To understand the expression and distribution of intercellular adhesion molecule-1 (ICAM-1), vascular cellular adhesion molecule-1 (VCAM-1) and CD45 (Leukocyte Common Antigen) in the control nondiabetic and various courses of diabetic rats retina. To explore the role of adhesion molecules (AMs) and the adhesion of leukocytes to vascular endothelial cells via AMs in diabetic retinopathy (DR).


METHODS
Sixty healthy adult male Wistar rats were randomly divided into diabetic groups (induced by Streptozotocin, STZ) and normal control groups. Rats in these two groups were further randomly divided into 3, 7, 14, 30, 90 and 180 days-group, including 5 rats respectively. The immunohistochemical studies of ICAM-1, VCAM-1 and CD45 were carried out in the retinal digest preparations or retinal paraffin sections, and the results were analyzed qualitatively, semi-quantitatively.


RESULTS
No positive reaction of VCAM-1 was found, and weak reactions of ICAM-1, CD45 were found in nondiabetic rats retina. The difference of 6 control groups had no statistical significance (P > 0.05). The increased ICAM-1 and CD45 staining pattern were detectable 3 days after diabetes induction, and a few VCAM-1 positive cells were observed in the retinal blood capillaries. The difference of diabetes and control is significant (P < 0.05). Following the course, the expressions of ICAM-1, VCAM-1 and CD45 were increasingly enhanced, reaching a peak at the 14th day.


CONCLUSIONS
Increased expression of ICAM-1, VCAM-1 and leukocytes adhering and stacking in retinal capillaries are the very early events in DR. Coherence of expression and distribution of the three further accounts for it is the key point for the onset of DR that AMs mediates leukocytes adhesion and endothelial cell injury.
Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, China.
Ningyan
N
Bai
Shibo
S
Tang
Jing
J
Ma
Yan
Y
Luo
Shaofeng
S
Lin
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000150:complications / Q000378:metabolism*; D003930:Diabetic Retinopathy / Q000209:etiology / Q000378:metabolism; D004730:Endothelium, Vascular / Q000378:metabolism; D018799:Intercellular Adhesion Molecule-1 / Q000096:biosynthesis*; D017493:Leukocyte Common Antigens / Q000096:biosynthesis*; D008297:Male; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012160:Retina / Q000378:metabolism; D019010:Vascular Cell Adhesion Molecule-1 / Q000096:biosynthesis*
D019010:Vascular Cell Adhesion Molecule-1; D018799:Intercellular Adhesion Molecule-1; D017493:Leukocyte Common Antigens