Characteristics of Purinergic Receptor Expressed in 3T3-L1 Preadipocytes

Abstract

Extracellular ATP elicits diverse physiological effects by binding to the G-protein-coupled P2Y receptors on the plasma membrane. In addition to the short-term effects of extracellular nucleotides on cell functions, there is evidence that such purinergic signalling can have long-term effects on cell proliferation, differentiation and death. The 3T3-L1 cell line derived from mouse embryo is a well-established and commonly utilized in vitro model for adipocytes differentiation and function. However, the distributions and roles of P2Y subtypes are still unknown in the preadipocyte. In this study, we identified the distributions and roles of P2Y subtypes in preadipocyte using Ca2+ imaging and realtime PCR. ATP increased the [Ca2+]i in a concentration-dependent manner. ATP increased Ca2+ in absence and/or presence of extracellular Ca2+. Suramin, non-selective P2Y blocker, largely blocked the ATP-induced Ca2+ response. U73122, a PLC inhibitor, completely inhibited Ca2+ mobilization in 3T3-L1 cells. The mRNA expression by realtime PCR of P2Y subtypes was P2Y2:P2Y5:P2Y6=1.0:12.5:0.3. In conclusion, we showed that P2Y5 receptor is a dominant purinergic receptor in preadipocytes, and multiple P2Y receptors could involve in differentiation and migration via regulating of intracellular calcium concentration.