Expression of beta 1- and beta 3-adrenergic-receptor messages and adenylate cyclase beta-adrenergic response in bovine perirenal adipose tissue during its transformation from brown into white fat.
Possible modifications of the beta-adrenergic effector system during the development of bovine perirenal brown adipose tissue (BAT) in utero and its transformation into white-like adipose tissue after birth were studied. The parameters assessed were the level of expression of beta 1-, beta 2- and beta 3-adrenergic receptor (AR) mRNAs and the response of the plasma-membrane adenylate cyclase to (-)-isoprenaline and to the beta 3-agonist BRL 37344. The beta 3-AR mRNA was found to be expressed very early in utero, i.e. before the third month of foetal life. Then it increased dramatically (9-fold) between month 6 of foetal life and birth. A high beta 3-AR mRNA level was maintained after birth up to an age of 3 months. After conversion of BAT into white-like adipose tissue, i.e. in the adult bovine, the beta 3-AR mRNA expression became small or not detectable, and the beta 1-AR mRNA, which was expressed much less than the beta 3-AR mRNA in foetal life, became predominant. A response of the adenylate cyclase to (-)-isoprenaline was observed in foetal life (3.1-fold stimulation). It decreased after birth (1.8-fold stimulation) and then remained constant until adulthood. A response to BRL 37344 was also observed in foetal life (1.8-fold stimulation). It was maintained after birth, but disappeared in the adult. A possible relationship between the beta-AR expression and the adenylate cyclase response to (-)-isoprenaline on the one hand and the uncoupling-protein expression on the other is discussed. The bovine might represent a good model to understand the transition from brown to white fat in the human.
Casteilla
L
L
Centre de Recherche sur l'Endocrinologie moléculaire et le Développement, CNRS, Meudon, France.
Muzzin
P
P
Revelli
J P
JP
Ricquier
D
D
Giacobino
J P
JP
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000273:Adipose Tissue / Q000196:embryology / Q000254:growth & development* / Q000378:metabolism; D002001:Adipose Tissue, Brown / Q000196:embryology / Q000254:growth & development* / Q000378:metabolism; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000375:Aging; D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D015342:DNA Probes; D004983:Ethanolamines / Q000494:pharmacology; D015870:Gene Expression; D007545:Isoproterenol / Q000494:pharmacology; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism*; D011943:Receptors, Adrenergic, beta / Q000235:genetics* / Q000502:physiology*
D000318:Adrenergic beta-Agonists; D015342:DNA Probes; D004983:Ethanolamines; D012333:RNA, Messenger; D011943:Receptors, Adrenergic, beta; C057368:BRL 37344; D000262:Adenylyl Cyclases; D007545:Isoproterenol