EVIDENCE FROM IN-VITRO DIFFERENTIATING CELLS THAT ADRENOCEPTOR AGONISTS CAN INCREASE UNCOUPLING PROTEIN MESSENGER-RNA LEVEL IN ADIPOCYTES OF ADULT HUMANS - AN RT-PCR STUDY

In vivo data have suggested that adrenergic signals can reactivate dor mant brown adipocytes in adult humans. We report here a system based o n primary cultures of perirenal adipocytes from human adults and rever se transcription-PCR of uncoupling protein mRNA. Norepinephrine and co mpounds classified as beta 3-adrenoceptor agonists in rodents increase d uncoupling protein mRNA level in human adipocytes (presumably brown adipocytes). Although we did not demonstrate that the observed effect was mediated by beta 3-adrenoceptors, it is proposed that this system could be used to appreciate the ability of beta-adrenoceptor agonists to activate UCP gene transcription and help to select beta 3-adrenocep tor agonists and antagonists prior to in vivo trials; indeed, the diff iculty in developing such drugs that are effective in humans may resul t from the fact that the screening of molecules has historically been made in rodents.