Uptake of Noradrenaline by Adrenergic Nerves, Smooth Muscle and Connective Tissue in Isolated Perfused Arteries and Its Correlation With the Vasoconstrictor Response
Year: 1968
Type: article
Abstract: Perfusion of the cat spleen with blood containing large quantities of noradrenaline causes the smooth muscle cells, when exposed to formaldehyde vapour, to develop the fluorescence characteristic of this catecholamine (Gillespie & Hamilton, 1967).The development of fluorescence is paralleled by the retention of noradrenaline assayed biochemically (Gillespie, Hamilton & Hosie, 1967).The smooth muscle cells differed both in the degree to which they retained noradrenaline and in the site of retention; in trabecular and capsular smooth muscle the fluorescence was slight and confined to the periphery of the cells, whereas in the smooth muscle of arteries the fluorescence was intense and present within the cells.In the perfused spleen it was difficult to be sure that all smooth muscle cells were equally exposed to noradrenaline and in the present experiments with an isolated length of artery perfused with saline it was hoped to minimize this difficulty so that the relationship between the concentration of noradrenaline and the degree of fluorescence could be determined.In the experiments on the spleen, the a-receptor blocking agent phenoxybenzamine prevented the development of fluorescence of arterial smooth muscle (Gillespie & Hamilton, 1966), suggesting that a-receptors might be involved in the uptake.If this were so, one would expect phenoxy- benzamine to interfere with the development of fluorescence and with the response in a parallel fashion.The vasoconstrictor response is easily measured in the perfused artery and it is therefore very suitable for this correlation.A brief account of some of these results has previously been published (Avakian & Gillespie, 1967). METHODSThe saline-perfused isolated artery preparation described by de la Lande & Rand (1965) was used.Rabbits of either sex in the weight range 1.8-2.8kg were anaesthetized with intravenous pentobarbitone
Authors: O. V. AVAKIAN, J. S. GILLESPIE
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W2036702791