Homogeneous or heterogeneous distribution of systemically administered adrenaline: Organ dependence

• Tipo: Artigo em Revista Científica Internacional
• Data: 1996

Autores

Brandao, F (Autor) Outra; Paiva, MQ (Autor) Outra; Albino Teixeira, A (Autor) FMUP; Maria Paula Serrão (Autor) Outra; Guimaraes, S (Autor) Outra

Revista

Título: Naunyn-Schmiedeberg's Archives of Pharmacology

Vol. 353

Páginas: 579-583

ISSN: 0028-1298

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 1 Citação

Scopus - 1 Citação

Outras Informações

ID Authenticus: P-001-EJA

Abstract (EN): In incubation experiments it was shown that exogenous adrenaline or noradrenaline does not distribute homogeneously into the adrenergic varicosities of the rat vas deferens (wall with thick and compact muscle layer) but does distribute homogeneously in the rat spleen capsule (thin and loose muscle layer, containing more extracellular space than the vas deferens). To circumvent any hypothetical role of the muscular layer in the distribution of the amine, 100 mu g.kg(-1).h(-1) adrenaline was administered to rats in vivo either i.v. (during 90 min) or i.p. (under pentobarbital anaesthesia, an Alzet minipump was implanted which delivered that dose during 6 days). The rats also received 100 mg.kg(-1) pargyline (to inhibit MAO) and 100 mg.kg(-1) tropolone (to inhibit COMT). At the end of adrenaline administration, vasa deferentia and spleen capsule were removed, washed and then exposed to 100 mu mol.l(-1) tyramine for 20 min. At the end of this exposure, the ratio noradrenaline/adrenaline in the tissue and in the medium was compared. In the vas deferens both after i.v. and i.p. administration of adrenaline, the ratio noradrenaline/adrenaline was about 3 times higher in the medium than in the tissue, while in the spleen capsule the ratio noradrenaline/adrenaline was not significantly different in the medium and in the tissue. We conclude that, even when the amine reaches the storage sites from the blood, it distributes homogeneously in the spleen capsule and heterogeneously in the vas deferens, perhaps because there are more than one kind of storage vesicles in the vas deferens.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 5