Table 1 Stages of diabetic retinopathy and corresponding levels of ET-1
From: Diabetic retinopathy and endothelin system: microangiopathy versus endothelial dysfunction
Pre-clinical diabetic retinopathy (haemodynamic and hystopathological abnormalities) | Clinical diabetic retinopathy (clinically visible lesions) | Severe diabetic retinopathy (pre-proliferative and proliferative diabetic retinopathy) |
|---|---|---|
ET-1 increased | ET-1 decreased | ET-1 and ET-3 increased |
Activation of ECs/pericytes and mitogenic effect on VSMCs | Reduced action on pericytes and VSMCs | Upregulation of ECs, pericytes, and VSMCs |
Increased extent of microangiopathy | Capillary dilation, microaneurysms, and fluid leakage | Capillary occlusion, ischemia, and neovascularization |
