Dopamine plasma membrane transporter (DAT) in rat thymus and spleen: an immunochemical and immunohistochemical study.
The expression of the dopamine plasma membrane transporter (DAT) was investigated in rat thymus and spleen by immunochemical and immunohistochemical techniques. Antibodies raised against a peptide mapping near the amino terminus of DAT were bound to a single band of approximately 76 kDa in thymus and spleen membranes as well as in striatal and kidney membranes which were used as dopaminergic reference tissues. Reverse transcription-polymerase chain reaction analysis revealed that both thymus and spleen expressed DAT mRNA. Immunohistochemistry revealed in rat thymus a DAT immune reaction in the wall of arteries located in septa of connective tissue as well as in the medulla, with a reticular localization and an apparent negative reaction of thymocytes. In the spleen, DAT immunoreactivity was located primarily in the red-white pulp marginal zone, within small cells, likely corresponding to lymphocytes and in the wall of white pulp arteries. The presence of a dopamine transporter suggests that dopamine released in the lymphoid microenvironment may contribute to neuroimmune modulation. It cannot be excluded a different activity of dopamine in primary and secondary immune organs, such as maturation and selection of lymphocytes and activation of immune responses in the spleen.
Mignini
F
F
Anatomia Umana, Dipartimento di Medicina Sperimentale e Sanitá Pubblica, Universitá di Camerino, Via Scalzino 3, 62032 Camerino, Italy.
Traini
E
E
Tomassoni
D
D
Amenta
F
F
D000818:Animals; D050483:Dopamine Plasma Membrane Transport Proteins / Q000032:analysis / Q000096:biosynthesis / Q000378:metabolism*; D007150:Immunohistochemistry; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013154:Spleen / Q000378:metabolism*; D013950:Thymus Gland / Q000378:metabolism*
D050483:Dopamine Plasma Membrane Transport Proteins; D012333:RNA, Messenger