[Effect of low - level He - Ne laser irradiation on biomechanical property of wound healing process in healthy and streptozotocin induced diabetic rats]

ABSTRACT

The aim of present investigation was to determine the effects of low-level He-Ne laser therapy on biomechanical property of skin wound of healthy and streptozotocin induced diabetic [STZ-D] rats. The study was performed by experimental method. 36 male adult Wistar rats weighing above 250 gr. were used. Rats were divided equally into control and experimental groups, each group [n=18] were equally divided into 3 subgroups in order to radiate 3 different energy densities of laser. Weight of healthy and diabetic rats were recorded in the beginning and at the end of study. Blood glucose of rats in the beginning of study was recorded and rats with more than 120 mg/dl were excluded from study. Diabetes was induced by one time intra peritoneal injection of 55 mg/kg STZ. After one month, hyperglycemia was established in experimental group. Two 15-mm, vertical incision wounds were made on the dorsum of rats. Three groups of healthy and diabetic rats were received 22.4J/cm[2], 1.2J/cm[2] and 4J/cm[2] energy densities He-Ne laser for two weeks. At the end of study, rats were killed and skin sample were extracted and were submitted to a biomechanical evaluation [maximum force] examination. Data was analyzed by paired student t test methods. Mean value of blood glucose of diabetic rats was 518.37 +/- 23.3. Laser-treated healthy rats with 1.2J/cm[2] energy density showed significant increase of maximum force [p=0.05]. Laser-treated diabetic rats with 4J/cm[2] energy density showed significant increase of maximum force [p=0.05]. It seems ideal parameters for effectiveness of Low- Level He-Ne laser in healthy and diabetic rats are different. Wounds of diabetic rats should be radiated with more energy density of low- level laser for accelerating wound healing process in comparison with healthy rats