Antipeptide antibodies differentiate between long and short isoforms of the D2 dopamine receptor

We have developed specific antibodies directed against two synthetic peptides corresponding to defined sequences in the D2 dopamine receptor. One peptide is from a region that is present only in the 'long' isoform of the receptor, whereas the other is from a region that is common to both. These antibodies are able to recognize the native receptor as judged by immunocytochemical staining of cells transfected with dopamine receptor DNA. One antibody was shown to be specific for the 'long' form of the receptor and reacts only with cells transfected with the 'long' DNA subtype and not with those transfected with the 'short' DNA subtype. This recognition is specific and can be inhibited by the corresponding free peptide and not by a non-relevant peptide.