D-Carnitine hydrochloride ((S)-Carnitine Hydrochloride) is a constituent of striated muscle and liver. It is used therapeutically to stimulate gastric and pancreatic secretions and in the treatment of hyperlipoproteinemias.

Competitive ligand binding assay.: Ligand binding is performed using lysates from COS-7 cells transfected with expression plasmids for VDR or RXRα. Binding is performed overnight at 4°C in lysate buffer with 0.71 nM (18 Ci/mmol) [3H]1,25(OH)2D3 and bile acid competitor. Unbound [3H]1,25(OH)2D3 is removed by adsorption to dextran-coated charcoal and the supernatant removed for scintillation counting. Ki values are calculated from a computer fit of competition curves from triplicate assays.