Divergent effects of an alpha2-adrenergic antagonist on lipolysis and thermogenesis: interactions with a beta3-adrenergic agonist in rats.
Divergent effects of an alpha2-adrenergic antagonist on lipolysis and thermogenesis: interactions with a beta3-adrenergic agonist in rats.
复制标题
α2-肾上腺素能拮抗剂对脂肪分解和产热的不同作用：与大鼠中β3-肾上腺素能激动剂的相互作用。
DOI：
10.3892/ijmm.8.1.103
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发表时间：
2001
影响因子：
5.4
通讯作者：
Alfredo Martínez
中科院分区：
文献类型：
--
作者：
J. Gómez;G. Frühbeck;M. Aguado;F. Milagro;Javier Margareto;Alfredo Martínez
This study was undertaken in order to test the hypothesis that selective beta3-AR stimulation and simultaneous blockade of alpha2-AR would result in an increase of lipolysis and thermogenesis in rats. Incubation of isolated white adipocytes with the alpha2-AR antagonist yohimbine produced a concentration-dependent increase in glycerol release (P<0.001) for all assayed concentrations (10-12-10-6 M) and potentiated the lipolytic effect of the beta3-AR agonist Trecadrine. However, in vivo administration of yohimbine produced a marked decrease in body temperature (1.3-1.5 degrees C, P<0.001) and blocked the thermogenic effect of Trecadrine when simultaneously administered. A similar response was observed for whole body oxygen consumption. Furthermore, yohimbine did not modify brown adipose tissue oxygen consumption, but blocked the beta3-AR-mediated increase triggered by Trecadrine. Brown adipose tissue UCP-2 and -3 mRNA expression was not changed by yohimbine. In conclusion, the present work indicates that in vitro alpha2-AR blockade by yohimbine potentiates the beta3-AR-mediated stimulation of lipolysis. On the other hand, in vivo alpha2-AR antagonism blocks the thermogenic effects mediated by beta3-AR stimulation, suggesting a possible interplay between the receptors.
