Abstract: Objective To investigate the changes in aorta morphology and Ca2 +-activated K+ (KCa) channel expression in the
diabetic rats. Methods A diabetic rat model was established by a single intraperitoneal injection of streptozotocin (30 mg/kg)
after a modified high fat and glucose diet for 8 weeks. Pathological changes in the aorta were observed with HE staining,
elastic fiber staining, Masson’s trichrome staining and immunohistochemistry. Both the mRNA and protein levels of KCa
channels in the aorta were measured by RT-PCR and Western blotting. Results Early atherosclerotic changes were observed in
the aorta wall of the diabetic rats. The mRNA and protein levels of KCa1.1 channel α- and β-subunits were significantly
decreased, while the expression of KCa3.1 channels was obviously enhanced in the middle layer of the aorta in the diabetic rats.
Conclusion KCa channel switching in smooth muscles may play a role in the development of atherosclerosis in diabetic rats.