The distribution of [14C]sucrose within the skeletal muscle of the rat in vitro.

1. The distribution of [(14)C]sucrose within the plantaris muscle of the rat has been examined by suspending muscles in oxygenated Ringer containing this marker and subsequent analysis of the muscle.2. Histological examination of sections of muscle treated in this way indicates considerable distortion of muscle fibre pattern; this has been held to cast doubt upon the validity of such a method as a means of extracellular space examination.3. The rate of K(+) loss from muscles under these conditions has been examined by flame photometry. Up to 50% of the original muscle K(+) has been shown to be lost by efflux within approximately 1 hr from the commencement of soaking.4. It is considered that these findings indicate severe deterioration in the physiological condition of the muscle, and it is suggested that tissue hypoxia is chiefly responsible for this.