Evelyn M. Anderson

Elaboration of Hormones by Pituitary Cells Growing in vitro

Conclusion With growth in vitro, pars intermedia cells of the posterior lobe of the pituitary retain their power to elaborate melanophore-expanding principle. Under the conditions of experiment no discernible production of hormones took place with growth of anterior lobe cell in vitro. We wish to thank Dr. K. I. Melville for his very kind assistance in the assay of posterior lobe hormone.

The Therapeutic Use of Potassium in Certain Cardiac Arrhythmias.

The investigation of the action of potassium salts on the heart dates from the time of Ringer, 1 whose classical experiments on the frog heart are well known. Irrespective of osmotic tension, the necessity of sodium, potassium and calcium ions in a balanced solution was proved. Hering 2 stopped paroxysmal ventricular tachycardia and ventricular fibrillation in the dog, and many investigators including Rothberger and Winterberg, 3 Anrep, 4 and Wiggers 5 have similarly obtained immediate cessation of both auricular and ventricular ectopic rhythms by intravenous or intracardiac injections of solutions of potassium chloride. Wiggers 5 suggested the possibility of its therapeutic use in ventricular fibrillation of accidental electrocution. It thus seemed reasonable to attempt to disturb the calcium-potassium ratio in favor of potassium for certain other therapeutic reasons. Scherf 6 and others have demonstrated a reversal of the customary actions of potassium and calcium when used intravenously on ventricular ectopic rhythms caused by aconite. The calcium eliminated the aberrant beats, while the potassium precipitated showers or paroxysms of them. It is predicted that some cases may be encountered clinically in which the arrhythmias show such a paradoxical response to potassium. Norn 7 showed an increment in blood potassium of 21% 40 minutes after the oral administration of 12 gm. of potassium chloride; and 61% increment in 2 hours. An appreciable increment was obtained in 30 minutes after 2 gm. of KCl in 2 of our cases. Potassium salts were used clinically to check attacks of paroxysmal ectopic ventricular tachycardia, and to prevent the occurrence of auricular and ventricular ectopic beats. Four different soluble potassium salts were used: potassium chloride, potassium iodide, potassium citrate, and potassium acetate, all with apparently identical effect. It is presumed that the anion and acid-base influences are negligible.

A Preliminary Investigation of the Source of the Creatinuria Following Transection of the Spinal Cord

Summary It has been shown that the creatine excreted in large amount following spinal cord transection originates mainly from the muscle tissue which has been affected by the cord transection. Creatine half-life in the “spinal” dog was 38 days. The rate of disappearance of body creatine in the dog (estimated to be about 2% per day) is compatible with that found for other species.