THE ENHANCEMENT OF REVASCULARIZATION OF SKELETAL-MUSCLE TRANSPLANTS USING THE BETA(2)-AGONIST ISOPRENALINE

The effect of the beta(2)-agonist isoprenaline on the revascularisatio n and regeneration of skeletal muscle transplants was studied using hi stological, morphometric and autoradiographic methods. Revascularisati on of the transplants was accelerated in the isoprenaline-treated mice as evidenced by histological and autoradiographic results. The number s of presumptive satellite cells were increased in the isoprenaline-tr eated mice. Significant increases in muscle cytoplasmic volume, endoth elial cell volume, capillary and myofibre numbers, and the numbers of myofibres with peripheral nuclei were also found in transplants remove d from the isoprenaline-treated mice (compared with controls). Reducti ons in myonuclear volume, 'other tissue' volume and numbers of myofibr es with no nucleus sectioned were also found in transplants from isopr enaline-treated mice. Although there was an increased volume of regene rated muscle in the transplants, it cannot be concluded that this was because of the earlier transplant revascularisation, as beta(2)-agonis ts have been shown to have a hypertrophic effect on skeletal muscle.