Abstract
Rectal temperature and oxygen consumption (üüO2) were monitored in female rats acclimated either to cold or to thermoneutrality and with and without chronic administration of oestradiol. The hormone is known to inactivate brown adipose tissue (BAT) and to reduce its response to noradrenaline (NA). The role of sympathetic control was studied by administering NA or the adrenergic blocker propranolol. Oestradiol treatment did not affect rectal temperature in the states of acclimation to thermoneutrality and to cold, nor did it change the hypothermic response of cold-exposed rats to temporary food deprivation. In the cold-acclimated rats, both controls and oestradiol-treated animals exhibited similar degrees of metabolic reduction after propranolol administration in the cold and similar degrees of metabolic activation by NA at thermoneutrality. Rats acclimated to thermoneutrality showed a larger metabolic response to NA when treated with oestradiol. The results suggest that oestradiol, while inactivating the BAT response to NA, activates the NA responsiveness of other metabolically active tissues in cold-induced thermogenesis. The observation of a greater oxidative capacity in the kidney and the rectus abdominis muscle of oestradiol-treated, cold-acclimated rats would be in line with this proposal.
References
Colquhown EQ, Clark MG (1991) Open question: Has thermogenesis in muscle been overlooked and misinterpreted? NIPS 6:256–259
Fregly MJ, Black DJ, Kelleher DL, MacArthur SA (1977) Tolerance of oestrogen-treated rats to acute cold-exposure (Abstract). Federation Proc 36:419
Himms-Hagen J, Behrens W, Hbous A, Greenway D (1976) Altered mitochondria in skeletal muscle of cold-acclimated rats and the adaptations for nonshivering thermogenesis. In: Jansky L, Musacchia XJ (eds) Regulation of depressed metabolism and thermogenesis. Charles C Thomas. Publisher, Springfield, pp 243–260
Laudenslager ML, Wilkinson CW, Carlisle HJ, Hammel HT (1980) Energy balance in ovariectomized rats with and without estrogen replacement. Am J Physiol 238:R400-R405
Puerta ML, Nava MP, Abelenda M, Fernandez A (1990) Inactivation of brown adipose tissue thermogenesis by oestradiol treatment in cold-acclimated rats. Pflügers Arch Eur J Physiol 416:659–662
Puerta M, Abelenda M, Nava MP, Fernandez A (1993) Reduced noradrenaline responsiveness of brown adipocytes isolated from oestradiol-treated rats. Can J Physiol Pharmacol 71:(in press)
Richard D (1986) Effects of ovarian hormones on energy balance and brown adipose tissue thermogenesis. Am J Physiol 250:R245-R249
Williams LT, Lefkowitz RJ (1977) Regulation of rabbit myometrial alpha adrenergic receptors by estrogen and progesterone J Clin Invest 60:815–818
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Fernández, A., Abelenda, M., Nava, M.P. et al. Oxygen consumption of oestradiol-treated rats. Pflügers Arch. 426, 351–353 (1994). https://doi.org/10.1007/BF00374793
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00374793