| Author |
Arduini, Arduino Indiveri, Cesare Pochini, Lorena Bonomini, Mario Pandolfi, Assunta Scalise, Mariafrancesca Belviso, Stefania Di Silvestre, Sara |
| Description |
Author Affiliation: Pochini L ( 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.); Scalise M ( 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.); Di Silvestre S ( Department of Medical, Oral and Biotechnological Sciences, University 'G. d'Annunzio' CeS.I., Via Luigi Polacchi, 11, 66013 Chieti, Italy.); Belviso S ( 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.); Pandolfi A ( Department of Medical, Oral and Biotechnological Sciences, University 'G. d'Annunzio' CeS.I., Via Luigi Polacchi, 11, 66013 Chieti, Italy.); Arduini A ( CoreQuest Calabria, Via P. Bucci 4C, 87036 Arcavacata di Rende, (CS), Italy); Bonomini M ( Department of Medicine, Institute of Nephrology, G. d'Annunzio University, Via dei Vestini, Chieti-Pescara, Italy.); Indiveri C ( 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.) |
| 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. |
