Chick embryo, cholesterol

Fetal or neonatal brain prior to myelination contains relatively little cholesterol and in this respect the composition is similar to that of other body tissues. However, during this period before myelin is laid down, microscopic examination shows that small lipid droplets appear in variable number within the nervous tissue. In the human spinal cord droplets appear up to the twenty-second week of fetal life and in the chick embryo up to the sixteenth day of incubation. It would appear from histochemical reactions (Adams and Davison, 1959) that these droplets contain hydro-phobic lipids such as cholesterol esters or triglyceride. Chemical analyses... 

A summary of the principal metabolic pathways for the conversion of cholesterol to steroid hormones, intermediates, and metabolites together with porphyrin-inducing activities is presented in Fig. 5 [65]. The chick embryo liver cell tissue culture method was used for the determinations, and the inducing activities were related to the intensity of porphyrin fluorescence as observed in a fluorescence microscope. 

Metabolism of cholesterol in the chick embryo. II. Isolation and chemical nature of... 

We used chick-embryo hepatocytes to examine the availability of different cholesterol sources as precursors for bile acids. Our... 

Key Words Chick-embryo hepatocytes. Cholesterol, HDL, Tauro-Cholic acid, Taurochenodeoxycholic acid. 

Eggs contain the complete food supply for the embryo chick and consequently are rich in essential nutrients. Since they contain very little carbohydrate they cannot be considered as a complete food for humans. The white of eggs consists almost entirely of protein with ovalbumin constituting 70% of the total. The yolk contains the phosphoprotein vitellin and 21-33% of fat including phospholipids and cholesterol. 

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