Homogeneous or heterogeneous distribution of systemically administered adrenaline: Organ dependence

• Type: Article in International Scientific Journal
• Date: 1996

Authors

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

Journal

Title: Naunyn-Schmiedeberg's Archives of Pharmacology

Vol. 353

Pages: 579-583

ISSN: 0028-1298

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 1 Citation

Scopus - 1 Citation

Other information

Authenticus ID: 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.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 5