INVESTIGADORES
VATTA Marcelo Sergio
artículos
Título:
Angiotensin 111 modulates noradrenaline uptake and release in the rat hypothalamus
Autor/es:
PAPOUCHADO ML; VATTA MS; CESAR CASALE; BIANCIOTTI LG; FERNADEZ BE
Revista:
JOURNAL OF AUTONOMIC PHARMACOLOGY
Editorial:
John Wiley & Sons Ltd
Referencias:
Año: 1995 vol. 15 p. 1 - 8
ISSN:
0144-1795
Resumen:
1 Effects of angiotensin I11 (A 111) on 'H-noradrenaline ('H-NA) total, neuronal andnon-neuronal uptake, 'H intracellular distribution and release were studied in vitro inthe rat hypothalamus.2 A 111 (1 p ~ d)ecr eased total, neuronal and non-neuronal 'H-NA uptake whenhypothalamic slices were incubated with 'H-NA for 30 min. A I11 effects on neuronaland non-neuronal 3H-NA uptake were determined in the presence of 100 PM hydrocortisoneor 10 PM cocaine hydrochloride, respectively. The effect of A I11 on total'H-NA uptake was blocked by 10 p~ Ile7 angiotensin I11 (Ile' A 111), an antagonistat A I11 receptors. In contrast, 100 nM A I11 had no effect on 'H-NA uptake.3 The study of the 3H-NA uptake time course showed that 1 ,LLM A111 decreased NAuptake at 1, 3, 7, 15 and 30min incubation.4 In hypothalamic slices preloaded with 'H-NA for 30 min, 1 PM A111 increased the'H content in the granular pool and decreased it in the cytosolic pool.5 Spontaneous 'H release was also modified by 1 p~ A I11 when hypothalami werepreloaded with 'H-NA for 30 min. A 111 increased the spontaneous output of 'H. Thiseffect was receptor-mediated since the effect of A I11 on 3H release was antagonizedby Ile7 A 111.6 The present results suggest that the effects of A I11 on NA neurotransmission, maybe involved in the regulation of central angiotensin effects such as blood pressurecontrol, hydrosaline balance and dipsogenesis, through modulation of central sympatheticactivity.