The in Vitro Action of Acth on the Oxygen Consumption of Slices of Cattle Adrenal Cortex

Abstract

A technique for measuring the action of small doses of ACTH on the oxygen consumption of slices of cattle adrenal cortex is described.The oxygen consumption rate of such slices in vitro is increased by ACTH. A linear relationship between logarithm of the dose of ACTH and the percentage increase in the rate of oxygen uptake is obtained with this method, and its suitability for biological assay purposes has been investigated.The question of the specificity of this action of ACTH is discussed.The energy metabolism of the adrenal cortex has been investigated by several workers in recent years. Carpenter, McLeod & Reiss [1946] found increased oxygen uptake values in the adrenal cortices of rats treated with ACTH. Gemzell [1948] and Reiss & J. M. M. Halkerston [1950] showed that treatment of rats with ACTH increased the phosphorylization rate of the adrenals. Tepperman [1950] using dog adrenal slices, Saffran, Bayhss & Webb [1951] bisected rat adrenals and Ferstl, Heppich & Schmid [1951] cattle adrenal cortex shces, demonstrated that ACTH added to the incubation medium brought about an in¬ crease in oxygen uptake and a decrease in the ascorbic acid content of the tissues used.Overbeek & van der Vies [1952] reported that the increase in oxygen consumption rate and decrease in ascorbic acid content of surviving adrenal cortex slices found in vitro experiments was not a specific effect of ACTH, as preparations inactive in the adrenal ascorbic depletion test [Sayers, Sayers & Woodbury, 1948] showed the same ability to increase the oxygen-uptake rate as active preparations.However, a direct action of ACTH on surviving adrenal tissue has been shown by Vogt [1951] and Pincus, Hechter & Zaffaroni [1951], using the isolated perfused gland; by Saffran, Grad & Bayliss [1952] and Haynes, Savard & Dorfman [1953] using bisected rat adrenals and cattle adrenal cortex slices respectively. The action was demonstrated by increased hormone production as estimated by biological assay, chemical analysis or radioactive isotope techniques. This report describes an improved technique for assessing the effect of different substances on the respiratory metabolism of surviving adrenal cortex tissue. The technique has been apphed to a study of the action of ACTH on such tissue and the relation between the in vivo activity of ACTH and the in vitro effect.

The Influence of Steroid Hormones on the Energy Metabolism of the Adrenal Cortex in Vitro

“…For instance, it is known that the ascorbic acid content of surviving adrenal cortex slices is diminished after incubation with ACTH or DOC [Tepperman, 1950;Saffran et al 1951;Ferstl et al 1951]. As shown in this and a previous paper (Reiss et al [1953]), the presence of glucose or pyruvate is essential for the increase of the oxygen consumption by DOC or ACTH. Depletion of these substrates, or of high energy phosphorus compounds which play an essential role in the carbohydrate metabolism, must also be considered as causal factors.…”

“…Many of the clinical and physiological actions of testosterone thus become more understandable, as, for instance, the well-known therapeutic action of testosterone in pituitary cachexia and the improvement in the response of the adrenal cortex of some patients, as recently shown by Reiss [1953].…”

“…In a previous paper [Reiss, Brummel, Halkerston, Badrick & Fenwick, 1953], it was described how the adrenocorticotrophic hormone (ACTH) of the anterior pituitary lobe increased the oxygen uptake of cattle adrenal cortex slices.…”

The Pituitary and Adrenals

“…A method for determination of ACTH in blood of hypophysectomized dogs has been described (214) as also in blood of intact human beings (215). The in 'lJitro stimulation of oxygen uptake of adrenal cortex slices from cattle has been suggested for ACTH assay (216) as has an in vitro frog skin test (217). (218) and electro phoretic studies (219) continue to indicate the heterogeneity of relatively pure preparations of somatotrophin.…”

Some Effects of Adrenal Cortical Steroids on Intermediary Metabolism

“…The adrenal steroids have a less specific effect on brain tissue. Although a decrease in Q 02 has been shown, this appears to correlate with the anaesthetic action of these steroids rather than their carbohydrate-regulating capacity (Gordan, 1956 , 1952), whereas corticotrophin is known to increase the respiration of this tissue (Reiss, Brummel, Halkerston, Badrick, and Fenwick, 1953). Some of these glucocorticoid effects resulting from studies in vitro have been summarized in Table III. 1.…”