The simultaneous oxidation of substrates by rat liver mitochondria [proceedings].

present study is consistent with there being no difference in glycaemia in the animals, suggesting that abnormalities of carbohydrate metabolism had not developed at this age. It has been shown that calorie supplementation of the diet during suckling can lead to a persistent increase in body lipid content, at least up to 60 days (Wurtman & Miller, 19766). The effect of excess calorie intake on enzyme parameters was studied by oral intubation of overnourished rats with glucose (equivalent to 10% of the total expected daily calorie intake) from 4 to 20 dayspostpartum. This additional calorie burden during suckling on animals already in an overnourished state (through restriction of litter size) accelerated some of the enzyme abnormalities which develop in overnourished rats at 20 weeks. Thus already by 12 weeks the glucose-supplemented overnourished rats showed significant increases in lipogenic enzyme activities and of body weight compared with unsupplemented overnourished animals. It is noteworthy that in these ‘supernourished’ rats hyperglycaemia was also apparent. The effects of glucose supplementation on the rate of development of enzyme abnormalities suggests that these abnormalities are the result of extra calorie intake during the suckling period rather than of excess intake of a specific dietary component of rat milk. I t is concluded that overnourishment of rats during suckling can result in the appearance in later life of enzyme abnormalities characteristic of obesity and may predispose the animals towards this condition. The study emphasizes the importance of early nutritional influences in the sensitive preweaning period on the metabolic integrity of the fully developed adult organism.