BACKGROUND This investigation examined the possibility that the inhibitory effect of halothane on nonshivering thermogenesis (heat production) in brown adipocytes is not a universal effect of all anesthetic agents but related to the type of anesthetic. METHODS Brown adipocytes from hamster were isolated with a collagenase digestion method and incubated with anesthetic agents. The rate of oxyg...

Participation of brown adipose tissue [through the action of the uncoupling protein-1 (UCP1)] in adaptive adrenergic nonshivering thermogenesis is recognized, but the existence of a response to adrenergic stimulation in UCP1-ablated mice implies that a mechanism for an alternative adaptive adrenergic thermogenesis may exist. Here, we have used UCP1-ablated mice to examine the existence of an al...

Introduction Probably mainly as an effect of the global obesity epidemic, the scientific interest in thermogenesis has increased dramatically in recent years. The questions asked are principally: are (some) forms of obesity due to decreased metabolism? – and can (some) forms of obesity be treated by an increased thermogenesis? Although these questions are rather clear, evaluation of the thermog...

Male and female rats were fed standard laboratory chow or a highly palatable diet (cafeteria diet) for 10 wk. The cafeteria diet caused an increase in caloric intake and in body weight, and it induced thermogenesis that was associated with elevated plasma triiodothyronine (T3) levels, increased brown adipose tissue size, and enhanced metabolic response to norepinephrine. For a comparable calori...

Okamatsu-Ogura Y, Kitao N, Kimura K, Saito M. Brown fat UCP1 is not involved in the febrile and thermogenic responses to IL-1 in mice. Am J Physiol Endocrinol Metab 292: E1135–E1139, 2007. First published December 12, 2006; doi:10.1152/ajpendo.00425.2006.—The activity of brown adipose tissue (BAT), a site of nonshivering metabolic thermogenesis, has been reported to increase after interleukin (...

The activity of brown adipose tissue (BAT), a site of nonshivering metabolic thermogenesis, has been reported to increase after interleukin (IL)-1beta/lipopolysaccharide injection. To clarify the possible contribution of BAT thermogenesis to whole body febrile response, we investigated febrile and thermogenic response to IL-1beta using mice deficient in uncoupling protein-1 (UCP1), a key molecu...

From mouse to man, brown adipose tissue (BAT) is a significant source of thermogenesis contributing to the maintenance of the body temperature homeostasis during the challenge of low environmental temperature. In rodents, BAT thermogenesis also contributes to the febrile increase in core temperature during the immune response. BAT sympathetic nerve activity controlling BAT thermogenesis is regu...

To investigate the involvement of the periaqueductal gray (PAG) in the control of non-shivering thermogenesis, we tested the effects of electrical or chemical stimulation of the PAG on thermogenesis of brown adipose tissue (BAT) in urethane anesthetized rats. Electrical stimulation (0.1 mA, 33 Hz, 0.5 ms) or application of d,l-homocysteic acid (0.5 mM, 0.3 ml) into the lateral region of the cau...

After decades of controversies about the quantitative importance of autoregulatory adjustments in energy expenditure in weight regulation, there is now increasing recognition that even subtle variations in thermogenesis could, in dynamic systems and over the long term, be important in determining weight maintenance in some and obesity in others. The main challenge nowadays is to provide a mecha...

Infants rats depend on heat production by brown adipose tissue (BAT) during cold challenge. Although it has been suggested that BAT thermogenesis protects the heart in the cold, the relationship of BAT activation to cardiac rate has not been examined directly. In the first experiment, the cardiac rate of 2- and 7- to 8-day-old rat pups was monitored during moderate and extreme cold challenge. P...