Effects of torbafylline, pentoxifylline and buflomedil on vascularisation and fibre type of rat skeletal muscles subjected to limited blood supply.

1. Blood flow (measured by radio-labelled microspheres), fibre composition and capillary/fibre ratio were estimated in rat fast twitch skeletal muscles (tibialis anterior and extensor digitorum longus) five weeks after unilateral ligation of the common iliac artery in animals treated with either saline, torbafylline, pentoxifylline or buflomedil. 2. The resting blood flow was lower in muscles with limited blood supply than in their contralateral controls; this difference became statistically insignificant after treatment. Capillary/fibre ratio was similar in all muscles with either intact or limited blood supply and did not change after administration of any of the drugs. 3. The percentage of glycolytic fibres was not changed by ligation, but it decreased significantly in animals treated with torbafylline. This may improve performance in muscles with limited blood supply.