ADRB3 and type 2 diabetes mellitus: A third original finding from the MD-Lipolysis Study is that adipose tissue from Obese-IR and Obese-T2D showed reduced mRNA abundance of the β3-adrenergic receptor (ADRB3), which drives catecholamine-induced lipolysis via cAMP signalling [50]; and of gap junction protein alpha 1 GJA1, also known as connexin 43, which propagates catecholamine signalling by allowing the diffusion of cAMP between connected adipocytes [49].