Lladó Isabel, Rodríguez-Cuenca Sergio, Pujol Esperanza, Monjo Marta, Estrany M Elena, Roca Pilar, Palou Andreu
Laboratori de Biologia Molecular, Nutrició i Biotecnologia, Departament de Biologia Fonamental i Ciències de la Salut, Universitat de les Illes Balears, Palma de Mallorca, Spain.
Obes Res. 2002 Apr;10(4):296-305. doi: 10.1038/oby.2002.41.
To investigate the effects of short-term (15 days) cafeteria-diet feeding on the expression of alpha- and beta-adrenergic receptors (AR) and its association with lipolytic stimulation in isolated retroperitoneal white adipocytes.
Six female and 6 male Wistar rats (4 weeks old) were fed a cafeteria diet plus standard diet for 15 days. The remaining 12 age- and sex-matched rats received a standard diet only. White retroperitoneal adipose tissue was isolated and used for the determination of both alpha(2) and beta-AR expression and for in vitro studies of lipolytic activity.
In female control rats, we found higher lipolytic capacities located at the postreceptor level and a lower alpha(2)/beta(3)-AR ratio than male rats. Cafeteria-diet feeding for 15 days decreased lipolytic activity in both male and female rats and altered the alpha(2A)- and beta(3)-AR protein levels with an increase of alpha(2A)-AR in males and a beta(3)-AR decrease in females.
Our results indicate that a 15-day cafeteria-diet feeding induced an increase in the alpha(2)/beta(3)-AR balance and impaired adipose tissue lipolytic activity, which was higher in males and may contribute to the development of increased fat mass. The higher functionality of alpha(2)-AR, together with the minor role developed by beta(3)-AR and lower lipolytic capacities located at the postreceptor level in cafeteria-diet-fed male rats compared with female rats, may be responsible for the gender-dependent differences observed in this study.
研究短期（15天）自助餐式饮食喂养对分离的腹膜后白色脂肪细胞中α和β肾上腺素能受体（AR）表达的影响及其与脂解刺激的关系。
6只雌性和6只雄性Wistar大鼠（4周龄）喂食自助餐式饮食加标准饮食15天。其余12只年龄和性别匹配的大鼠仅接受标准饮食。分离腹膜后白色脂肪组织，用于测定α(2)和β-AR表达以及脂解活性的体外研究。
在雌性对照大鼠中，我们发现受体后水平的脂解能力较高，且α(2)/β(3)-AR比值低于雄性大鼠。15天的自助餐式饮食喂养降低了雄性和雌性大鼠的脂解活性，并改变了α(2A)-和β(3)-AR蛋白水平，雄性大鼠中α(2A)-AR增加，雌性大鼠中β(3)-AR减少。
我们的结果表明，15天的自助餐式饮食喂养导致α(2)/β(3)-AR平衡增加，脂肪组织脂解活性受损，雄性大鼠的这种情况更严重，这可能导致脂肪量增加。与雌性大鼠相比，自助餐式饮食喂养的雄性大鼠中α(2)-AR功能更高，β(3)-AR发挥的作用较小，且受体后水平的脂解能力较低，这可能是本研究中观察到的性别差异的原因。
