The CB1 receptor and the splice variant CB1a are localized mainly in the brain.1,2,3 The CB1 receptor is a G-protein coupled receptor that binds the active component of cannabis, Δ9-tetrahydrocannabinol. Human and rat CB1 receptors exhibit 97.3% homology at the amino acid level over the complete protein, and 100% homology within the peptide sequence used to make this antibody.4,1 This peptide exhibits no homology with the CB2 receptor. Based on the amino acid sequence, the CB1 receptor has a molecular weight of approximately 52,800.1 The CB1 receptor and the splice variant CB1a are localized mainly in the brain, whereas the CB2 receptor is localized predominantly in peripheral tissues, including the spleen and hemopoietic cells.4,1,2,3 Cayman’s CB1 Receptor Polyclonal Antibody can be used for Western blot applications. The antibody recognizes the N-terminal extracellular region of the CB1 receptor at 40 kDa from human samples.WARNING This product is not for human or veterinary use.