Role of exercise training on pulpal blood flow in diabetic rats.

The purpose of this study was to determine the role of exercise training on blood flow in diabetic dental pulp. Male Spraque-Dawley rats were divided into three groups of control (CON), diabetes (STZ), and diabetes with exercise-trained (STZ + Ex) groups. Diabetes was induced by intravenous injection of streptozotocin (STZ; 55 mg/kg.bw). The exercise training protocol consisted of treadmill running, 5 times/week with the velocity of 13-15 m/min for 30 min. At 12 weeks (wks) and 24 wks after the STZ injection, the laser Doppler flowmeter (Model ALF 21, USA) was used to measure pulpal blood flow (PBF) while the animals were anesthetized with sodium pentobarbital (50 mg/kg.bw). The results showed that STZ rats developed hyperglycemia, hypertriglyceridemia, higher mean arterial blood pressure, higher heart weight, body weight loss, and lower of PBF in the intact right lower incisor. Exercise training has beneficial effect on physiological characteristics of diabetic condition including triglyceride level, mean arterial blood pressure, heart rate, and heart weight. Interestingly, reduction of the PBF was restored in STZ + Ex rats. In conclusion, our observations indicate that exercise training can prevent the reduction in PBF of STZ-induced diabetic rats.