Quantitative study of the microvascular pattern in tourniquet-induced muscle ischemia.

Experiments were carried out on 40 adult Wistar rats to determine the effect of the application of a pneumatic tourniquet on the capillary network of the tibialis anterior muscles. The tourniquet was applied for four hours to the right hind limb above the knee. During the degeneration processes (6 to 24 hours postischemia), the capillary density and capillary-to-fiber ratio decreased significantly with respect to a control group of untreated animals. In the subsequent regenerative processes, there was a greater increase of fiber density than of capillary density, resulting in a capillary-to-fiber ratio lower than that of the control group. In the last period (30 to 90 days postischemia), both capillary density and fiber density returned to normal values.