Cold-Acclimation and the Role of Catecholamines in Body Temperature Regulation in Male Leghorns

Abstract

THE existence of nonshivering thermogenesis, an increase in metabolic rate in the absence of muscle electrical activity upon cold exposure, has been well established to occur in cold-acclimated mammals, i.e., rats (Sellers et al., 1954), rabbits (Carlson, 1955), the wild Norway rats (Heroux, 1962), the golden hamster (Pohl and Hart, 1963) and man (Davis and Johnston, 1961) particularly in neonates (Brück and Wünnenberg, 1965a; Karlberg et al., 1962; Moore and Underwood, 1962). The development of nonshivering thermogenesis in mammals is associated with the calorigenic response of norepinephrine and other catecholamines from the sympathetic nervous system (Hsieh and Carlson, 1957; Hsieh et al., 1957; Brück and Wünnenberg, 1965b; and Heim and Hull, 1966). This led Brück to suggest that the development of nonshivering thermogenesis during cold acclimation involves the reestablishment of the neonatal thermoregulatory mechanism (Brück and Wunnenberg, 1966). As far as birds are concerned, there is evidence indicating the existence…