Postnatal development of organic cation transport in the rat liver

• Tipo: Artigo em Revista Científica Internacional
• Data: 1998

Autores

Martel, F (Autor) FMUP; Martins, MJ (Autor) FMUP; Calhau, C (Autor) FCNAUP; Hipolito Reis, C (Autor) Outra; Azevedo, I (Autor) Outra

Revista

Título: Pharmacological Research

Vol. 37

Páginas: 131-136

ISSN: 1043-6618

Editora: Elsevier

Indexação

ISI Web of Knowledge - 24 Citações

Scopus - 27 Citações

Classificação Científica

FOS: Ciências médicas e da saúde > Medicina básica

Outras Informações

ID Authenticus: P-001-8M8

DOI: 10.1006/phrs.1997.0283

Abstract (EN): Previous studies have demonstrated that the small permanently charged organic cation 1-methyl-4-phenylpyridinium (MPP+) is avidly taken up by rat hepatocytes. The aim of this study was to characterise the postnatal development of hepatic uptake of organic cations, using the model compound MPP+. Accumulation of [H-3]MPP+ by liver slices obtained from rats ranging from 1 day to 7 weeks was measured, and the effect of a series of compounds on [H-3]MPP+ uptake was examined. The accumulation of [H-3]MPP+ by liver slices was similar in adult (87.5 +/- 19.9 pmol g(-1); n = 7) and neonatal rats (110.6 +/- 11.5 pmol g(-1); n = 15). Verapamil, quinidine (100 mu M) and progesterone (200 mu M) produced very marked reductions on [H-3]MPP+ uptake at all ages, and the inhibitory effect of verapamil and quinidine was maximum in livers from 1-day-old rats. Bilirubin (200 mu M) significantly reduced [H-3]MPP+ uptake by liver slices from 1 day, 1 week and 7-week-old rats. However, [H-3]MPP+ accumulation was reduced by cimetidine, vinblastine and daunomycin (100 mu M) in 1-day-old rats, but the effect of these drugs disappeared as the animals age increased. These findings demonstrate that hepatic organic cation uptake capacity is remarkably high shortly after birth and suggest that at least two distinct uptake mechanisms are involved in this process. These uptake systems are the type I hepatic transporter of organic cations, active from birth to adulthood, and P-glycoprotein, active only in very young rats. (C) 1998 The Italian Pharmacological Society.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 6