Background:

IC50: 13 nM (binding at the human β3 adrenergic receptor) [1]

Benzenesulfonamide derivative L-755,507 is a partial agonist for the human β3 receptor, with maximal activation 52% of that evoked by isoproterenol [2]. β3 adrenergic receptor is a G protein-coupled receptors which can enhancement of lipolysis in adipose tissue.

In vitro: L-755,507 displays an excellent activity profile as an extremely potent human β3 adrenergic receptor agonist (β3 EC50 0.43 nM), with >440-fold selectivity over β1 and β2 binding [1]. L-755,507 is also a potent and selective b3 partial agonist in rhesus monkeys as assessed by its affinity for the cloned b adrenergic receptors, and stimulates lipolysis in rhesus adipocytes with an EC50 = 3.9 nM [2].

In vivo: Dose rhesus monkeys with L-755,507 elicits lipolysis and metabolic rate elevation. The ED50 for glycerolemia was 0.03 mg/kg and the ED50 for tachycardia was 2.5 mg/kg, and stimulates metabolic rate by