Acts as a receptor for L-lactate and mediates its anti-lipolytic effect through a G(i)-protein-mediated pathway. Highly expressed in subcutaneous fat and omental fat and detectable in lower levels in brain and many other tissues. High levels detected in epididymal and subcutaneous fat with slightly lower in omental fat, low levels are detected in the brain, skeletal muscle, kidney, liver and the pancreas (at protein level). Belongs to the G-protein coupled receptor 1 family.