Targeted gene disruption reveals a leptin-independent role for the mouse beta3-adrenoceptor in the regulation of body composition.
J Clin Invest
; 100(5): 1098-106, 1997 Sep 01.
Article
en En
| MEDLINE
| ID: mdl-9276726
Targeted disruption of mouse beta3-adrenoceptor was generated by homologous recombination, and validated by an acute in vivo study showing a complete lack of effect of the beta3-adrenoceptor agonist CL 316,243 on the metabolic rate of homozygous null (-/-) mice. In brown adipose tissue, beta3-adrenoceptor disruption induced a 66% decrease (P < 0.005) in beta1-adrenoceptor mRNA level, whereas leptin mRNA remained unchanged. Chronic energy balance studies in chow-fed mice showed that in -/- mice, body fat accumulation was favored (+41%, P < 0.01), with a slight increase in food intake (+6%, NS). These effects were accentuated by high fat feeding: -/- mice showed increased total body fat (+56%, P < 0.025) and food intake (+12%, P < 0.01), and a decrease in the fat-free dry mass (-10%, P < 0.05), which reflects a reduction in body protein content. Circulating leptin levels were not different in -/- and control mice regardless of diet. The significant shift to the right in the positive correlation between circulating leptin and percentage of body fat in high fat-fed -/- mice suggests that the threshold of body fat content inducing leptin secretion is higher in -/- than in control mice. Taken together, these studies demonstrate that beta3-adrenoceptor disruption creates conditions which predispose to the development of obesity.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Composición Corporal
/
Proteínas
/
Receptores Adrenérgicos beta
Límite:
Animals
Idioma:
En
Revista:
J Clin Invest
Año:
1997
Tipo del documento:
Article
País de afiliación:
Suiza
Pais de publicación:
Estados Unidos