Catecholamine elevation in iron deficiency.

Iron-deficient rats have increased blood and urinary catecholamines regardless of whether anemia is or is not present. The catecholamine response in both iron-deficient and control animals is largely temperature dependent, showing little difference at the isothermic temperature of 30 degrees C but a two- to threefold increase in iron-deficient animals over controls at lower temperatures. The iron-deficient rat is unable to maintain body temperature at 4 degrees C and this is independent of anemia or of food intake. When animals are run on the treadmill for 4 h, body temperatures increase but the difference observed at 4 degrees C between iron-deficient and control animals persists. The underlying abnormality in temperature regulation and in catecholamine response disappeared after 6 days of iron therapy.