Effect of Insulin Injections Upon Plasma Free Fatty Acids (F.F.A.) and Lipolysis of Adipose Tissues of White Leghorn Hens

Abstract

INSULIN, parenterally administered into mammalian species leads to a fall of plasma free fatty acids (F.F.A.) (Engel, 1962; Vaughan and Korn, 1962). In contrast, administration of insulin into domestic fowl leads to an increase in plasma F.F.A. (Heald et al., 1965; Lepkovsky et al., 1967). Heald et al. (1965) suggested that the action of insulin was due to a glucagons impurity since adipose tissue of the fowl is very responsive to treatment with glucagon (Grande, 1970; Heald et al., 1965). That the increase in plasma F.F.A. in response to administration of insulin was due to insulin was shown by Lepkovsky et al. (1967) who used glucagon-free insulin. While increases in plasma F.F.A. have been used as an index of mobilization of free fatty acids from the adipose tissues, (Gibson and Nalbandov, 1966), it is possible for plasma F.F.A. to originate elsewhere such as in the triglycerides of the blood. If…