INVESTIGADORES
VATTA Marcelo Sergio
artículos
Título:
Bile Secretion Is Centrally Regulated by C-Type Natriuretic Peptide
Autor/es:
SABBATINI M; VATTA MS; VESCINA C; CASTRO JL; FERNADEZ BE; BIANCIOTTI LG
Revista:
CELLULAR AND MOLECULAR NEUROBIOLOGY.
Editorial:
SPRINGER/PLENUM PUBLISHERS
Referencias:
Lugar: New York; Año: 2002 vol. 22 p. 755 - 770
ISSN:
0272-4340
Resumen:
1. Current evidence supports that C-type natriuretic peptide (CNP) is the brain natriureticpeptide. Natriuretic peptide receptors and mRNA CNP have been reported in theliver and in discrete areas and nucleus of the central nervous system involved in the regulationof gastrointestinal physiology. In the present work, we sought to establish the roleof CNP in the central regulation of bile secretion in the rat and to delineate the possiblepathways and mechanisms involved.2. To examine the role of CNP on bile secretion, the peptide was applied in the brainlateral ventricle (1, 10, and 100 ng/¹L) and bile samples were collected every 15 min for60 min. The role of the autonomic nervous system in CNP response was assessed by atropineor combined phentolamine and propranolol administration.3. Centrally applied CNP diminished basal as well as bile salt-evoked bile flow in adose-dependent manner. CNP reduced bile acid output as well as sodium and potassiumexcretion, supporting CNP effect on bile acid-dependent flow. CNP also decreased chlorideexcretion and increased bile pH. The excretion of total glutathione was not affected bycentrally applied CNP suggesting that this peptide does not alter bile acid-independentflow. Neither parasympathetic nor sympathetic blockade abolishedCNPinhibitory responseon bile secretion. Mean arterial pressure and portal venous pressure were not modifiedby CNP.4. Present findings show that centrally applied CNP modulates bile secretion in a dosedependentfashion. CNP alkalinized bile and reduced bile acid-dependent flow withoutaffecting bile acid-independent flow. The inhibitory response of CNP on bile secretion wasnot mediated by the autonomic nervous system. Present findings give further support to therole of CNP as the brain natriuretic peptide.