The Influence of Phlorhizin on Intestinal Absorption

It was discovered by v. Mering1) that phlorhizin, when given in moderate quantities through the mouth causes glucosuria in animals, but in larger quantities it induces, in addition to this, some diarrhoea, the cause of which is not yet clear.As this poison, as far as my ex periments on rabbits are concerned, has no direct effect whatever upon the peristaltic movements of the intestine, the cause of the diarrhoea would be ascribed to its action to prevent the absorption of the fluid in the intestine.To determine whether this poison retains the absorption of water directly, or whether it does so indirectly by preventing the ab sorption of some substances dissolved in it, seems to be very interesting not only in explaining the mechanism of phlorhizin diarrhoea, but also in inferring that of the glucosuria produced by the same poison.The mechanism of the glucosuria after phlorhizin has been sub jected by many investigators, and it has experimentally proved by Minkowski1), Frey3), Zuntz4) and many others that the glucosuria is not due to hyperglucaemia, but to the change of the function of the kidney.But the nature of this alteration in the renal function has not yet been quite satisfactorily explained.Pavy, Brodie and Siau5) and Loewi6) believed, without any valid evidence, that phlorhizin causes the epitherial cells of the tubules to form sugar from the protein of the blood and to secrete this in the urine.But this view was contradicted by Cushny7).According to him, in the normal kidney the sugar of the blood is filtered through the glomerular capsule and then reabsorbed