Data/hora: 02/06/2024 09:24:26

Provedor de dados: | Brazilian Journal of Medical and Biological Research
País: | Brazil
Título: | Changes in the electrophysiological parameters of the posterior intestine of Anguilla anguilla (Pisces) induced by oxytocin, urotensin II and aldosterone
Data: | 1997-01-01
Ano: | 1997
Palavras-chave: | Intestine; Anguilla anguilla; Oxytocin; Urotensin II; Aldosterone.
Resumo: | In view of the importance of the intestine in the osmoregulation of freshwater fishes, we determined the effects of oxytocin, urotensin II (UII), and aldosterone added to the serosal side of the isolated posterior intestine of the freshwater-adapted teleost Anguilla anguilla on electrophysiological parameters. Oxytocin decreased the short-circuit current (SCC) and transepithelial potential difference (TPD) at concentrations of 1 and 10 mU/ml (to 50% and 42% of control values, respectively), but did not alter these parameters at a concentration of 0.1 mU/ml. UII reduced SCC and TPD at concentrations of 10 nM, 50 nM and 100 nM (to 85% of control values), but increased these parameters at the concentration of 500 nM (to 115% of control values). Aldosterone did not alter SCC or TPD at the concentrations tested (10 nM and 100 nM). Oxytocin may open Na+ channels in the apical membrane, allowing the flow of Na+ to the serosa, reducing SCC and TPD. Should this hypothesis be correct, oxytocin would be important for freshwater adaptation, since it would increase Na+ absorption. The reduction of SCC and TPD in the posterior intestine of A. anguilla induced by UII is evidence that this neurohormone is also important for freshwater adaptation in teleosts. Aldosterone did not show this effect probably due to the lack of receptors in this organ
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000100006
Editor: | Associação Brasileira de Divulgação Científica
Relação: | 10.1590/S0100-879X1997000100006
Formato: | text/html
Fonte: | Brazilian Journal of Medical and Biological Research  v.30 n.1 1997
Fonte: | info:eu-repo/semantics/openAccess