title: Acetylcholine and acetylcarnitine transport in peritoneum: Role of the SLC22A4 (OCTN1) transporter.
abstract: A suitable experimental tool based on proteoliposomes for assaying Organic Cation Transporter Novel member 1 (OCTN1) of peritoneum was pointed out. OCTN1, recently acknowledged as acetylcholine transporter, was immunodetected in rat peritoneum. Transport was assayed following flux of radiolabelled TEA, acetylcholine or acetylcarnitine in proteoliposomes reconstituted with peritoneum extract. OCTN1 mediated, besides TEA, also acetylcholine and a slower acetylcarnitine transport. External sodium inhibited acetylcholine uptake but not its release from proteoliposomes. Differently, sodium did not affect acetylcarnitine uptake. These results suggested that physiologically, acetylcholine should be released while acetylcarnitine was taken up by peritoneum cells. Transport was impaired by OCTN1 inhibitors, butyrobetaine, spermine, and choline. Biotin was also found as acetylcholine transport inhibitor. Anti-OCTN1 antibody specifically inhibited acetylcholine transport confirming the involvement of OCTN1. The transporter was also immunodetected in human mesothelial primary cells. Extract from these cells was reconstituted in proteoliposomes. Transport features very similar to those found with rat peritoneum were observed. Validation of the proteoliposome model for peritoneal transport study was then achieved assaying transport in intact mesothelial cells. TEA, butyrobetaine and Na(+) inhibited acetylcholine transport in intact cells while efflux was Na(+) insensitive. Therefore transport features in intact cells overlapped those found in proteoliposomes.
authors.affiliation: Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, (CS), Italy.
authors.forename: Lorena
authors.initials: L
authors.lastname: Pochini
authors.affiliation: Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, (CS), Italy.
authors.forename: Mariafrancesca
authors.initials: M
authors.lastname: Scalise
authors.affiliation: Department of Medical, Oral and Biotechnological Sciences, University "G. d'Annunzio" CeS.I., Via Luigi Polacchi, 11, 66013 Chieti, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Di Silvestre
authors.affiliation: Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, (CS), Italy.
authors.forename: Stefania
authors.initials: S
authors.lastname: Belviso
authors.affiliation: Department of Medical, Oral and Biotechnological Sciences, University "G. d'Annunzio" CeS.I., Via Luigi Polacchi, 11, 66013 Chieti, Italy.
authors.forename: Assunta
authors.initials: A
authors.lastname: Pandolfi
authors.affiliation: CoreQuest Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, (CS), Italy; Department of Research and Development, CoreQuest Sagl, Tecnopolo, Via Cantonale 18, 6928 Manno, Switzerland.
authors.forename: Arduino
authors.initials: A
authors.lastname: Arduini
authors.affiliation: Department of Medicine, Institute of Nephrology, G. d'Annunzio University, Via dei Vestini, Chieti-Pescara, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Bonomini
authors.affiliation: Department DiBEST (Biologia, Ecologia, Scienze della Terra) Unit of Biochemistry and Molecular Biotechnology, University of Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, (CS), Italy. Electronic address: cesare.indiveri@unical.it.
authors.forename: Cesare
authors.initials: C
authors.lastname: Indiveri
mesh_terms: D000108:Acetylcarnitine / Q000737:chemistry / Q000378:metabolism*; D000109:Acetylcholine / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D001693:Biological Transport, Active; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D027701:Organic Cation Transport Proteins; D010537:Peritoneum / Q000737:chemistry / Q000378:metabolism*; D011510:Proteolipids / Q000737:chemistry / Q000378:metabolism; D051381:Rats; D012964:Sodium / Q000737:chemistry; D000070590:Solute Carrier Proteins; D027981:Symporters
chemical_list: D002352:Carrier Proteins; D008565:Membrane Proteins; D027701:Organic Cation Transport Proteins; D011510:Proteolipids; C000705567:Slc22a4 protein, rat; D000070590:Solute Carrier Proteins; D027981:Symporters; C020485:proteoliposomes; D000108:Acetylcarnitine; D012964:Sodium; D000109:Acetylcholine
keywords: Acetylcarnitine; Acetylcholine; Inflammation; Membrane transport; OCTN1; Proteoliposomes