Abstract
LONDON. Royal Society, February 26.—E. H. Starling and E. B. Verney: The secretion of urine, as studied on the isolated kidney. The mechanism of urinary secretion in mammals has been studied by perfusing the dog's kidney with the heart-lung preparation. The glomeruli filter from the blood plasma its non-protein constituents. Hydrocyanic acid suspends tubular activity, while the action of hydrocyanic acid is reversible. Urea, sulphate, and, when present in the serum, phenosulphonephthalein, are secreted by the tubule cells into the glomerular filtrate. Water, chloride, bicarbonate, and glucose are re-absorbed by the tubule cells from the glomerular nitrate. Water appears to be re-absorbed lower down the tubule than chloride. Pituitrin causes a marked increase in the percentage and absolute amounts of chloride and a decrease in the amount of water eliminated. Substances of this type normally regulate the output of water and chloride in the intact animal, and the characters of the urine secreted by the isolated organ are due in large part to their absence.-F. Eicholtz and E. H. Starling: The action of inorganic salts on the secretion of the isolated kidney. Calcium working on a background of potassium leads to an increase of chloride excretion and water output, due to decreased re-absorption in the tubules. These salts, if given separately, have no definite effects. Inorganic phosphates decrease the output of water and chlorides by turning the calcium ion into a colloidal form. To this colloidal form the glomerulus membrane is impermeable. Cyanide increases the permeability of the glomerulus membrane and allows the colloidal phosphates to appear in the urine.-G. V. Anrep: A new method of crossed circulation. The method consists in an arterial anastomosis between a heart-lung preparation and the descending aorta or the brachio-cephalic artery of another animal. Thus the part of the animal connected with the heart-lung preparation receives its blood supply from the latter, while the remaining part of the animal continues to be fed by its own heart. The blood flow and the blood pressure of the perfused part of the animal is therefore under complete control.-G. V. Anrep and I de B. Daly: The output of adrenaline in cerebral anasmia, as studied by means of crossed circulation. In this condition there is an increased liberation of adrenaline from the suprarenal glands, which is due to a true secretion and not to redistribution of blood, and the increased secretion disappears after denervation of the suprarenal glands.-G. V. Anrep and E. H. Starling: Central and reflex regulation of the circulation. Mechanical rise in blood pressure in the brain inhibits the vasomotor centre and stimulates the cardio-inhibitory, the two centres acting synergetically to produce lowered pressure. Asphyxia by cerebral anaemia stimulates both vasomotor and cardio-inhibi-tory centres, the centres acting antagonistically, not synergetically. Andrenaline (small doses) introduced into head circulation causes slowing of heart and fall of pressure in lower half of animal. Measurement of pressure in Circle of Willis shows these effects are due to increased circulation through medullary centres, and cannot be ascribed to direct excitation of centres by adrenaline itself. The effects are analogous to, and produced in the same way as, those obtained on increasing pressure in head circulation.-K. Furusawa: Muscular exercise, lactic acid, and the supply and utilisation of oxygen. Part IX. Muscular activity' and carbohydrate metabolism in the normal individual. Results obtained are: On normal diet, carbohydrate only is responsible for the process of contraction and recovery from it. As duration of exercise is prolonged respiratory quotient of excess metabolism falls slowly, indicating that some substance other than carbohydrate is being called upon. On fatty diet, shortlived muscular exercise is performed at expense only of carbohydrate, as on normal diet. In long-continued exercise, fat takes part more quickly than on normal diet. In exercise of short duration, in which no change in general metabolism of body as a whole might be expected, the human body acts as though it were an isolated muscle, in which carbohydrate is the only substance oxidised, as shown by Meyerhof. The primary fuel of contraction, therefore, in human muscle is carbohydrate, and fat or protein is presumably used to replenish carbohydrate store disappeared. -A. Hunter and J. A. Dauphinee: (i) Quantitative studies concerning the distribution of arginase in fishes and other animals. (2) An approximative colori-metric method for the determination of urea with an application to the detection and quantitative estimation of arginase.-J. J. R. Macleod and N. A. McCor-mick: The effect on the blood-sugar of fish of various conditions, including removal of the principal islets (isletectomy).
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Societies and Academies. Nature 115, 357–359 (1925). https://doi.org/10.1038/115357a0
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DOI: https://doi.org/10.1038/115357a0