The effects of psychosocial stress on urinary excretion of adrenaline and noradrenaline in 51- to 55- and 71- to 74-year-old men.

The experiments were done to investigate modifications with aging in reactivity and speed of recovery of the sympathetic adrenomedullary system during psychosocial stress. Normal male volunteers were studied. Urinary adrenaline and noradrenaline, diuresis, pH and specific gravity were measured. Adrenaline and noradrenaline baseline levels were lower in the older age group. Adrenaline levels increased by the same percent during stress in the two age groups, but came back to pre-stress values more slowly in older subjects, as did blood pressure.