Detection of blood flow perfusion and post - occlusive reactive hyperemia in the skeletal muscle of rats.

Aims: Post-occlusive reactive hyperemia (PORH) remains poorly understood in the skeletal muscle system. This study was designed to validate an alternative strategy of PORH detection in rodents. Additionally, we explored the hypothesis that PORH is influenced by experimental models associated with impaired function of the skeletal muscle.

Materials And Methods: Wistar rats were anesthetized, and blood flow was assessed by laser Doppler in the anterior tibialis muscle, before and immediately after 5 s, 30 s, 3 min, or 5 min of flow occlusion, obtained through a cuff inflated to 300 mmHg around the thigh of the animals.

Key Findings: In healthy animals, deflating the cuff resulted in a fast increment of local blood flow, characterizing the PORH after 5 s to 5 min of cuff occlusion and its dependence on flow occlusion duration. Importantly, we found different profiles of PORH in animals pretreated with reserpine (accelerated peak and reduced half recovery time), streptozotocin (increased peak), or subjected to muscle contraction in stretching (delayed peak), approaches used as experimental models to study fibromyalgia, type II diabetes mellitus, and soreness induced by unaccustomed eccentric exercise, respectively.

Significance: We demonstrated that the profile of PORH in the anterior tibialis muscle of rats is sensitive to a variety of experimental models often associated with the skeletal muscle functionality, providing a useful strategy to explore how and whether changes in local regulation of blood flow can contribute to the development of skeletal muscle associated symptoms in clinically relevant conditions.