ULTRASTRUCTURAL DEMONSTRATION OF GLUCOSE-6-PHOSPHATASE ACTIVITY AND GLYCOGEN IN SKELETAL-MUSCLES OF NEWBORN PIGLETS WITH THE SPLAYLEG SYNDROME

The ultrastructural localization of glucose-6-phosphatase activity and glycogen were investigated in the longissimus dorsi and biceps femori s muscles of normal and splaylegged newborn piglets. Significant diffe rences were ascertained in the distribution of the reaction product of glucose-6-phosphatase activity between the two groups of animals. A f ine precipitate was found in the sarcoplasmic reticulum and in the per inuclear cisternae of normal piglet muscles. In splaylegged muscles, v ariable deposits of coarse reaction product were observed within the e xtremely dilated cisternae of sarcoplasmic reticulum at their peripher y. Moreover, both longitudinal and transversal ultrathin sections of t hese muscles showed a reduced number of myofibrils and an increased ac cumulation of glycogen (especially within the large extramyofibrillar spaces) in comparison with muscles of normal piglets.