<prompt> Dehydration increases the plasma concentration of all the following hormones EXCEPTVasopressinAldosteroneAngiotensin IIAtrial natriuretic peptide  <response>: D. i.e. Atrial natriuretic peptide 729- 30- Ganong 22nd 669-70- Ganong 23rdDEHYDRATION - loss of water from the body causes moderate decrease in ECF volume When ECF volume is decreased, BP falls, Glomerular capillary pressure declines and the GFR therefore falls reducing the amount of Na filtered. Tubular reabsorption of Na is amount, in part because the secretion of aldosterone is increased. Na excretion is decreased within a few minute and this rapid change in Na excretion occurs in adrenalectomiced subject. It is probably due to hemodynamic changes an possibly to decreased ANP secretion. 