title: Expression of the high-affinity choline transporter CHT1 in rat and human arteries.
abstract: The arterial vascular wall contains a non-neuronal intrinsic cholinergic system. The rate-limiting step in acetylcholine (ACh) synthesis is choline uptake. A high-affinity choline transporter, CHT1, has recently been cloned from neural tissue and has been identified in epithelial cholinergic cells. Here we investigated its presence in rat and human arteries and in primary cell cultures of rat vascular cells (endothelial cells, smooth muscle cells, fibroblasts). CHT1-mRNA was detected in the arterial wall and in all isolated cell types by RT-PCR using five different CHT1-specific primer pairs. Antisera raised against amino acids 29-40 of the rat sequence labeled a single band (50 kD) in Western blots of rat aorta, and an additional higher molecular weight band appeared in the hippocampus. Immunohistochemistry demonstrated CHT1 immunoreactivity in endothelial and smooth muscle cells in situ and in all cultured cell types. A high-affinity [3H]-choline uptake mechanism sharing characteristics with neuronal high-affinity choline uptake, i.e., sensitivity to hemicholinium-3 and dependence on sodium, was demonstrated in rat thoracic aortic segments by microimager autoradiography. Expression of the high-affinity choline transporter CHT1 is a novel component of the intrinsic non-neuronal cholinergic system of the arterial vascular wall, predominantly in the intimal and medial layers.
authors: Institute for Anatomy and Cell Biology, Justus-Liebig-University Giessen, Giessen, Germany. S.Lips@anatomie.med.uni-giessen.de
authors: Katrin S
authors: KS
authors: Lips
authors: Uwe
authors: U
authors: Pfeil
authors: Katja
authors: K
authors: Reiners
authors: Christoph
authors: C
authors: Rimasch
authors: Klaus
authors: K
authors: Kuchelmeister
authors: Ruediger C
authors: RC
authors: Braun-Dullaeus
authors: Rainer V
authors: RV
authors: Haberberger
authors: Rupert
authors: R
authors: Schmidt
authors: Wolfgang
authors: W
authors: Kummer
mesh_terms: D000368:Aged; D000818:Animals; D001158:Arteries / Q000378:metabolism; D001345:Autoradiography; D015153:Blotting, Western; D002478:Cells, Cultured; D002794:Choline / Q000378:metabolism*; D004730:Endothelium, Vascular / Q000166:cytology / Q000378:metabolism*; D005260:Female; D005455:Fluorescent Antibody Technique; D006801:Humans; D008297:Male; D026901:Membrane Transport Proteins / Q000096:biosynthesis*; D008875:Middle Aged; D009130:Muscle, Smooth / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D026901:Membrane Transport Proteins; C065637:choline transporter; D002794:Choline