Dynamic Properties of Skeletal Muscle Contraction in Rats with Diabetes

The study was conducted on 20 white nonlinear male rats, which were divided into 2 groups of 10 animals each. Rats in the first group were used as control. Rats in the second groupwere induced type I diabetes by intraperitoneal (i.p.) administration of streptozotocin (65 mg/kg). Diabetes in rats was confirmed by the presence of hyperglycemia. For the establishment of nociceptive pain sensation, mechanical nociceptive test and tail-flick test were conducted in rats. Further animals were anesthetized by i.p. administration of Nembutal (40 mg/kg). The study of dynamic properties of muscle contraction was performed under conditions of the tibia muscle activation by using the modulated stimulation of efferent n. tibialis. Streptozotocin (STZ) was injected in rats; as a result, the blood glucose level was increased by 4.4 times (p ≤ 0.001). Pain sensitivity in diabetic rats was suppressed, indicating the development of peripheral neuropathy. In rats with diabetes, biomechanical parameters of tibia muscle contraction such as the maximum force of contraction, the speed of maximum force of contraction, the retention time of maximum force of contraction and integrated power of muscle contraction (it is calculated on the total area of the received force curves) were violated. This prevents adequate implementation motor neuron pools muscular system, which will have significant consequences in accurate positional movements.