The uptake of 131I by the thyroid of the rat has been investigated under various conditions of stress.The acute change always consists in a considerable reduction of the rate of uptake of 131I irrespective of the nature of the stress. This acute inhibition in the uptake of 131I is independent of the anterior pituitary lobe, since it occurs in the normal and hypophysectomized animal alike. It is also independent of the presence of the adrenals. The inhibition of the uptake of 131I by the thyroids occurs in vivo only; their ability to take up 131I in vitro is not impaired.All the acute changes seen under stress conditions can be readily reproduced by treatment with adrenaline, which shows the same inhibitory effect on normal and hypophysectomized animals, the action being equally transitory.It is suggested that the acute changes in thyroid function seen under stress conditions are entirely independent of the anterior pituitary and are caused by increased release of vasoconstrictor substances.An increased uptake rate of 131I by the thyroid was seen 24 hr after the acute stress. This was thought to be caused by a compensatory increase in the secretion of thyrotrophic hormone by the anterior pituitary.It has been reported previously [Haigh, Reiss & Reiss, 1954] that the rate of uptake of 131I by the human thyroid during the first hour after intravenous injection of this tracer may be considerably decreased in conditions of severe mental tension. This state was shown to be only transitory, since the thyroids of the investigated subjects showed a normal or even increased 24-hr uptake rate if their function was not other¬ wise disturbed. It was suggested that this initial inhibition of 131I uptake might be due to an increased concentration of vasoconstrictor substances in the blood. Supporting evidence was provided by preliminary experiments carried out on rabbits under Nembutal anaesthesia in which the uptake slope was completely flattened after intravenous infusion or injection of adrenaline.The investigations described in this paper were undertaken with the object of analysing the reaction of the thyroid to different stress conditions. A further purpose was to clarify and differentiate between the roles played by the pituitary, the adrenal and vasoconstrictor substances in the response of the thyroid to stress. METHODSThe rats used in this study were of the Wistar (Portón) strain. They were fed on Parkes' diet no. 41, and kept in a thermo-regulated room at 70 + 5°F. Hypophys¬ ectomy was performed by the paratracheal route and adrenalectomy by the dorsal route. 2i J. Endoc.
15 had no recurrence in 2-15 years. Niceberg and others (1956) report that 7 of 26 cases treated only by appendicectomy died of proven metastatic carcinoma within 5 years.It would appear that, provided there is no pseudomyxoma peritonei, the prognosis for mucocele is excellent, and for cystadenoma it is good, but with the latter there may be local recurrence. In adenocarcinoma the prognosis is very variable. In this series, of 6 patients with adenocarcinoma, 3 have died ( I was an incidental finding at necropsy) and the others were alive 14 years, 10 years, and 2 months after the operation. It would also appear that when the diagnosis of adenocarcinoma is made unexpectedly on microscopy in an appendix removed incidentally at another operation, the prognosis is good. SUlMlMARYAn account is given of 7 columnar-cell tumours of the appendix (6 adenocarcinomas and I cystadenoma) and 2 mucoceles. The terminology, treatment, incidence, pathogenesis, and prognosis are discussed.The only constant feature in the histological differentiation between an adenocarcinoma and a cystadenoma is that there is invasion of the wall in the former. A mucocele of the appendix is lined by flattened, cuboidal epithelium or by no epithelium. The presence of papillary projections suggests a cystadenoma rather than a mucocele.Acknowledgements.-We
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.
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