Methods for the study of dopamine receptors within lipid rafts of kidney cells

There is increasing evidence that G protein-coupled receptor (GPCR) signaling is regulated in lipid raft microdomains. GPCRs and GPCR-signaling molecules, including G proteins and protein kinases, have been reported to compartmentalize in these microdomains. Dopamine D(1)-like receptors (D(1)R and D(5)R) belong to a family of GPCRs that are important in the regulation of renal function. These receptors are not only localized and regulated in caveolae that contains caveolin-1 but are also distributed in non--caveolar lipid rafts which do not contain caveolin-1. This chapter describes detergent- and non-detergent-based methods to obtain lipid raft fractions from renal proximal tubule cells.