Vasoconstrictor responses to norepinephrine were determined during constant flow perfusion with warm Krebs solution in dog mesenteric arteries. The arteries were then stored 20—24 hours at 3°C in one of the following isosmotic solutions: Krebs, complex K (KC1, CaCl 2 , KHCO 3 , and glucose), NaCl, KC1, sucrose, or mannitol. After storage, arteries were again perfused with warm Krebs solution, a...