Ephedrine, a potential slimming drug, directly stimulates thermogenesis in brown adipocytes via beta-adrenoreceptors

Int J Obes. 1982;6(4):343-50.

Abstract

Ephedrine is a potential slimming drug that stimulates thermogenesis in man and laboratory animals. Considering that brown adipose tissue is an important site of catecholamine-induced thermogenesis in homeotherms, we tested the thermogenic efficiency of several ephedrine stereoisomers on adipocytes isolated from rat interscapular brown adipose tissue. Addition of (-)-ephedrine (0.1 mM) to brown adipocyte suspensions rapidly stimulated cellular respiration eight times above basal values. A stable Vmax of 335 nmol O2/min/10(6) cells was reached less than 5 min after the onset of respiratory stimulation. This value represents 85 percent of the maximal respiration observed with norepinephrine, the physiological effector of thermogenesis. The (-)isomer of ephedrine (1/2 Vmax = 20 microM) was more potent that other stereoisomers (+)-psi-ephedrine, (-)-psi-ephedrine (racephedrine) in enhancing brown adipocyte respiration. Beta-Adrenergic antagonists (alprenolol and propranolol) were much more effective than alpha-adrenergic antagonists (phentolamine and phenoxybenzamine) in inhibiting the respiratory effects of ephedrine. It is concluded that (-)-ephedrine mimics the calorigenic action of norepinephrine by directly stimulating brown adipocyte respiration via beta-adrenoreceptors.

Publication types

  • Comparative Study

MeSH terms

  • Adipose Tissue, Brown / cytology
  • Adipose Tissue, Brown / physiology*
  • Animals
  • Body Temperature Regulation / drug effects*
  • Cells, Cultured
  • Dose-Response Relationship, Drug
  • Ephedrine / pharmacology*
  • Female
  • Norepinephrine / pharmacology
  • Obesity / drug therapy
  • Oxygen Consumption / drug effects*
  • Propranolol / pharmacology
  • Rats
  • Rats, Inbred Strains
  • Receptors, Adrenergic / physiology*
  • Receptors, Adrenergic, alpha / physiology
  • Receptors, Adrenergic, beta / physiology*
  • Stereoisomerism
  • Stimulation, Chemical

Substances

  • Receptors, Adrenergic
  • Receptors, Adrenergic, alpha
  • Receptors, Adrenergic, beta
  • Propranolol
  • Ephedrine
  • Norepinephrine