Kathleen E. Roberts

Electrocardiographic Alterations Produced by a Decrease in Plasma pH, Bicarbonate and Sodium as Compared with those Produced by an Increase in Potassium

The effects of a decrease in plasma pH, bicarbonate and sodium on the electrocardiographic pattern are compared with those produced by elevation of serum potassium and lithium in the dog. The electrocardiographic alterations were found to be similar in form and progression. The alterations can be correlated with those found in isolated nerve and muscle preparations.

Elevation of Peripheral Blood Ammonia Following Muscular Exercise

Summary 1. Peripheral blood ammonia concentrations were elevated following convulsions due to electroshock therapy in patients, convulsions in dogs due to metrazol, and active voluntary exercise in human subjects. 2. The possibility that increase in circulating blood ammonia may be a factor in hyperpnea of muscular exercise is discussed.

Electrocardiographic Alterations Produced by an Increase in Plasma pH, Bicarbonate and Sodium as Compared with Those Seen with a Decrease in Potassium

The effects of an increase in plasma pH, bicarbonate and sodium on the electrocardiogram of the normal dog have been compared with those produced by a decrease in plasma potassium. The electrocardiographic alterations in these experimentally induced situations were found to be similar in form and progression.

Effects of Cortisone on Electrocardiographic Changes in Adrenal Insufficiency.

Discussion and Conclusions The changes in the electrocardiogram in adrenal insufficiency were found to parallel the alterations in plasma sodium and potassium; these were prevented with adequate maintenance dosages of cortisone but not corrected completely by this steroid after marked abnormalities in the electrocardiogram had occurred. This is in keeping with the concept ( 2 , 6 ) that the defects in cardiac function, found in adrenal insufficiency are the result of losses of body sodium and elevation of plasma potassium with a consequent imbalance of these ions. If this were the cause, it would be expected that abnormalities of the electrocardiogram would be reversed toward normal only by restoration or maintenance of adequate concentrations of sodium and potassium; such was found to be the case in our experiments. It is currently taught that the difference in potential which exists across the cell membrane is dependent, in part, upon the difference in concentration of potassium between the intra- and extracellular compartments. Alterations in this concentration, as are seen in conditions of hyperkalemia, result in a variety of disturbances in neuro-muscular activity and, more particularly, myocardial function ( 9 , 11 , 12 ), which result in such clinically overt findings as described above. In adrenal insufficiency it has been repeatedly observed( 4 , 5 , 7 ), that sodium chloride administration in adequate amounts will lower plasma potassium concentration and restore the electrocardiographic abnormalities toward normal; from this it would appear that these disturbances are directly related to abnormalities in sodium and potassium metabolism and are reversible only if adequate concentrations of these ions are restored. Since cortisone has been found to correct the renal functional defect on sodium excretion and to maintain normal plasma concentrations of sodium and potassium, it is conceivable that the disturbances in the electrocardiogram seen in adrenal insufficiency are effected by this steroid only in so far as it corrects the abnormalities in electrolyte metabolism.

A New Approach for Evaluating Differential Renal Function Utilizing a Mathematical Hypothesis.

Summary Neonatal thymectomy did not significantly reduce the size of the mast cell population in young and adult mice. Consequently, the thymus is not necessary for mast cell production during postnatal development.