In our study, we evaluated the effect of«ProCreatine» (ProCr),a novel membrane transporter-independent creatine modification on fatigability of the rat gastrocnemius muscle and portal vein smooth muscle using fatigue stimulation pools. The data obtained suggest the possibility of using ProCr as a therapeutic agent capable of reducing and correcting pathological conditions of the muscular system that arise during the processes of fatigue in skeletal muscles and smooth muscles of hollow organs.