Perfusion Staining Methods for Visualization of Intact Microvascular Networks in Whole Mount Skeletal Muscle Preparations.

Introduction: Visualization of the intact microvascular network in skeletal muscle requires labeling the entire network in whole mount preparations where muscle fibre length can be set to near optimal but the tools to do this are not clear.

Methods: We intravascularly injected CD-1 mice with different fluorescently labelled lectins (fluorescent isolectin GS-IB4 [ISO], wheat germ agglutinin [WGA], lycopersicon esculentum [LYCO]) or FITC-labelled gel. Soleus, extensor digitorum longus, diaphragm, gluteus maximus and cremaster muscles were excised, pinned at optimal sarcomere length and viewed using fluorescence microscopy.

Arteriolar and capillary responses to CO and H in hamster skeletal muscle microvasculature: Implications for active hyperemia.

Objective: We hypothesized that CO and H stimulate capillaries and arterioles to produce local and conducted vasodilations required to coordinate the distribution of blood flow to contracting skeletal muscle fibers.

Methods: CO and H independently and in combination were applied to 2A arterioles (first branch order from the 1A feed arteriole) and capillaries of the in situ, blood-perfused hamster cremaster muscle. The resulting local and conducted vasodilations were measured.