5HT4 Receptor/HTR4 (extracellular) Blocking Peptide (#BLP-SR036) is the original antigen used for immunization during Anti-5HT4 Receptor (HTR4) (extracellular) Antibody (#ASR-036) generation. The blocking peptide binds and ‘blocks’ Anti-5HT4 Receptor/HTR4 (extracellular) primary antibody, this makes it a good negative reagent control to help confirm antibody specificity in western blot and immunohistochemistry applications. This control is also often called a pre-adsorption control.