EFFECT OF COLD STRESS AND STARVATION ON THE CEREBRAL GLUCOSE-6-PHOSPHATE-DEHYDROGENASE ACTIVITY OF MALE GARDEN LIZARDS OF 3 DIFFERENT AGE-GROUPS

In the present study we observed that the cerebral glucose-6-phosphate dehydrogenase activity of male garden lizards did not change apprecia bly during maturation but showed a significant rise between middle-age d and old-aged groups. Whereas cold stress (1 h at 0-4-degrees-C) indu ced a significant increase in G6PDH activity of young animals, it caus ed a decrease in both middle-aged and old lizards. This decrease was m ore severe in the old group than in the middle-aged group. Another for m of stress, 72 hours of starvation, led to a significant increase in enzyme activity in young and in middle-aged lizards with young animals showing the greater effect. The old counter-parts showed a decrease i n enzyme activity after starvation stress.