Respiration of Kidney Cortex in High Potassium-Low Sodium Ringer's Solution. ∗

Abstract

Carr and Beck 1 have shown that in the brief life span of an albino rat after bilateral adrenalectomy there is a gradual decrease of about 25% in the basal metabolic rate, when the animal is maintained on a “normal” diet. The experiments reported here are part of a series designed to determine the cause and effect relationship of this decreased metabolic rate in the syndrome of adrenal insufficiency. In this instance an attempt was made to see whether the typical serum electrolyte picture in advanced adrenal insufficiency would reduce the respiration of kidney slices from normal rats. The kidney was chosen for study because of its importance in producing the adrenal insufficiency syndrome 2 and because it has been shown by Crismon and Field 3 that there is a decrease in kidney respiration in the adrenalectomized rat of about 38%.

Kidney slices were prepared with the Terry razor microtome which proved very satisfactory for this purpose. 4 The oxygen consumption of kidney cortex was measured by the Warburg method. 5 The suspension medium used in control experiments was the mammalian Ringer's of Dickens and Greville, 6 hereinafter termed D.G.-Ringer's. For the experimental series the medium was a high potassium-low sodium modification of mammalian Ringer's solution osmotically balanced with glucose, hereinafter called A.I.-Ringer's. The concentrations of electrolytes in this medium were those reported for blood of adrenalectomized animals by Grollman 7 and Hegnauer and Robinson. 8 The compositions of these solutions are summarized in Table I.

Thirty-two determinations were made in D.G.-Ringer's solution and 39 in the A.I.-Ringer's solution. Since the tissues were obtained from 9 white rats (Slonaker-Wistar strain), the arithmetic means of the results obtained on each animal were analyzed statistically as paired data. The mean oxygen consumption, N.P.T., per mg (dry weight) in one hour was 16.954 cu mm in D.G.-Ringer's solution and 16.098 cu mm in A.I.-Ringer's solution.