Objective: To investigate the expressions of 78-kDa glucose-regulated protein (GRP78) and Caspase-12 and their relationship with apoptosis in renal cortex of diabetic rats.
Methods: Uninephrectomized Wistar rats were used to induce diabetes by intraperitoneal injection of Streptozotocin (STZ 65 mg/kg). After 8 weeks, the expression and distribution of GRP78, Caspase-12, proliferating cell nuclear antigen (PCNA) were examined by immunohistochemistry. Flow cytometry was used to detect the levels of protein of GRP78 and Caspase-12. Apoptosis was evaluated by means of terminal deoxynucleotidyl transferase-mediated d-UDP nick-end labeling (TUNEL) and Flow cytometry. Serum creatinine, blood urea nitrogen and 24-hour urine protein excretion were checked.
Results: Compared with those in normal control group, the numbers of apoptosis and the expression of GRP78, Caspase-12 in glomerular and tubular cells were much higher in the diabetic kidneys at 8 weeks. There was no significant difference between group A and group B.
Conclusion: Activation of endoplasmic reticulum stress may play an important role in the development of diabetic nephropathy.