Atrial Natriuretic Factor Modifies the Biosynthesis and Turnover of Norepinephrine in the Rat Adrenal Medulla

FERNADEZ BE; LEDER M; FERNANDEZ G; BIANCIOTTI LG; VATTA MS

BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS

ACADEMIC PRESS INC ELSEVIER SCIENCE

Año: 1997 vol. 238 p. 343 - 346

0006-291X

In the present work we investigate atrial natriuretic on blood arterial pressure may be indirectly mediatedfactor (ANF) effects on the endogenous content, utili- through modifications of central as well as peripheralzation and turn over of norepinepinephrine (NE), on catecholamine metabolism (4-6).tyrosine hydroxilase (TH) activity, on cAMP and cGMP The atrial factor gene expression has been reported levels, and on phosphatidylinositol hydrolysis in rat adrenal medulla in order to assess the possible mecha- in the aortic arch, lung, anterior pituitary, centralnisms underlying ANF effects on NE metabolism. Re- nervous system, adrenal glands (including adrenalsults showed that ANF (5 mg/kg) increased NE endoge- medulla), the kidney and the gastrointestinal tractnous content (44%) and diminished the amine utiliza- (3,7). ANF immunoractivity and precursors, as welltion. On the other hand, the atrial factor (10 nM) as several mature forms of the atrial factor, haveinhibited both spontaneous and evoked, by 100 mM been identified in the chromaffin cells (8,9). FurtherKClTH, activity (48% and 59%, respectively).When sec- more, ANF binding sites also been reported in theond messenger systems were studied results showed adrenal medulla (10).that 10 nM ANF increased cGMP levels in adrenal me- We have previously reported that ANF modulateddulla (51%), while it modified neither cAMP levels nor noradrenergic neurotransmission in the central nerphosphatidylinositolhydrolysis. These results suggest vous system and norepinephrine (NE) activity in thethat ANF may play an important role in the modula- adrenal medulla of the rat. The atrial factor increasestion of the sympathoadrenergic system function, be- neuronal NE uptake and decreases neuronal NE rehavingas a putative neuromodulator.