Development Of Enzyme Systems In Chicken Embryo Heart Tissue
The development of some enzymes and enzyme systems necessary for energy metabolism in the hearts of developing chicken embryos was studied from day 7 through day 12. There was a 36% decrease in the protein present per g of wet tissue weight during this time period. A 242% increase in ETS activity per g of tissue and a 436% increase per mg of protein present was found. LDH activity was found to decrease 64% relative to mass and 44% relative to protein content. The overall glucose utilization decreased 83% when related to the mass of the hearts and 89% when related to the protein content. Thus, there was an increase in the dependence on the enzyme systems which require oxygen and are more efficient. There was also a decrease in the activity of the enzyme systems which do not require oxygen.