Dynamic control of calcium, phosphate, citrate, and glucose levels in blood serum. Effect of ACTH, adrenaline, noradrenaline, hydrocortisone, parathormone, insulin, and glucagon.

The effect of ACTH, adrenaline, noradrenaline, insulin, parathormone, hydrocortisone,and glucagonon the homeostaticmechanismcontrolling serum glucose,citrate, calcium, phosphorus,and potassium was studied in fasting rabbits and children. Citrate levelsare kept in balancebyACTH, adrenaline,and glucagon,which raisethe levels,and by insulin,which lowers them. Stressalone raisescitrate levels,probably through adrenalineand ACTH effects. Calcium levels in rabbits are markedly lowered by ACTH, given l.M., to tetany levels. Adrenaline hasa similar, but mild, effect. I. M. parathormone raisescalcium levels slowly. ACTH and parathormonemay be the antagonists in keeping calcium levelsconstant. Insulin, adrenaline, ACTH, glucagon, and parathormone lower phosphate levels. Major factors in lowering phosphatelevelsacutely evidentlyare insulin,which moves phosphateinto the cell, and parathormone,which movesit through the kidney. Insulin, adrenaline,ACTH, and glucagonlower potassiumlevelsin the rabbit. Only noradrenalinecausesa significant rise. In the normal child only citrate movesin the samedirection (elevates) as in the rabbit after ACTH.