Tissue glycogen levels in the Weddell seal, Leptonychotes weddelli: a possible adaptation to asphyxial hypoxia.

-1 . Glycogen contents of skeletal muscle, heart and brain cortex of fetal, month-old and adult Weddell seal, Leptonychotes weddelli, were determined. 2. Fetal, month-old and adult male levels ranged from 4"5 to 12-7, 9"1-13 and 1"5-1"8 mg glucose/g wet weight for muscle, heart and brain respectively. Pregnant female skeletal muscle levels were similar but heart and brain levels were 21.8 and 2"9 mg glucose/g wet weight respectively. 3. Heart and brain glycogen contents in the adult were two to three times those of other mammalian species, suggesting tissue storage for reliance on anaerobic glycolysis during episodes of diving asphyxia.