Fig. 2.

Pressure-volume (top panels) and pressure-compliance relations (bottom panels) in young (left panels) and older men (right panel) before (filled symbols) and during systemic adrenergic blockade (blocked; open symbols). Before adrenergic blockade calf venous compliance was reduced in older compared with young men. In response to adrenergic blockade calf venous compliance did not increase in young or older men, suggesting that adrenergic tone neither contributes to calf venous compliance in young or older men nor does it contribute to age-associated decreases in calf venous compliance in healthy men.