α1‐Adrenergic stimulation of Cl− efflux in isolated brown adipocytes

FEBS Letters

Connolly, Eamonn¹  Dasso, Leonardo¹  Nedergaard, Jan¹ 

[1] The Wenner-Gren Institute, University of Stockholm, The Arrhenius Laboratories F3, S-106 91 Stockholm, Sweden

关键词: Brown adipose tissue;    Cl− flux;    Membrane depolarization;    Nonshivering thermogenesis;    Prazosin;    (Hamster);   

DOI  :  10.1016/0014-5793(90)80144-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Unidirectional ³⁶Cl⁻ efflux from preloaded isolated brown adipocytes was studied. A norepinephrine-stimulated ³⁶Cl⁻ efflux pathway was found which approximately doubled the rate of ³⁶Cl⁻ efflux from the cells. The response to norepinephrine was fully inhibited by the α₁-adrenergic antagonist prazosin, but was unaffected by the β-adrenergic antagonist propranolol, showing that norepinephrine stimulated the ³⁶Cl⁻ efflux pathway via the α₁-adrenoceptor. The stimulation of ³⁶Cl⁻ efflux could not be mimicked by the Ca²⁺ ionophore A23187, indicating that the effect was not mediated by elevation of the intracellular Ca²⁺ level. It is concluded that brown fat cells possess a specific mechanism for α₁-adrenergic stimulation of Cl⁻ efflux. The possibility is discussed that this Cl⁻ efflux pathway could be the basis for the early α-adrenergic depolarization seen in brown fat cells.

【 授权许可】

Unknown