GLYCOGEN METABOLISM IN RABBIT KIDNEY UNDER DIFFERING PHYSIOLOGICAL STATES

¹ University Laboratory of Physiology, Oxford

Glycogen, has been assayed biochemically and histochemically in the kidney medulla. It is distributed very discretely in the epithelial cells of the collecting ducts of the papilla.

Histochemical and biochemical methods showed that glycogen levels are doubled in diuresis produced by administration of a water-load or mannitol. In antidiuresis, produced by dehydration or administration of deoxycorticosterone acetate, the glycogen levels are halved as compared with control kidney papillæ. The interstitial mucopolysaccharide structure of the papilla appeared thickened in antidiuresis and was dematous in diuresis, when compared with sections taken from control kidneys.

The glycogen content of the two kidneys of a single animal was not the same. Rabbit kidneys seemed to show a summing action, not working as a pair in parallel but giving a total response appropriate to the water balance of the whole animal.

It is suggested that the glycogen could be involved in the provision of energy for active transport processes involved in the transport of ions from the lumen of the collecting ducts to the papillary interstitium or alternatively, or in addition, could also act as a precursor for mucopolysaccharides of the papillary interstitium.

Note:

I should like to thank Professor Sir G. L. Brown for the privilege of working in his laboratory. The Oxford University Laboratory of Physiology and the London Hospital Medical College both provided publication grants. I am extremely grateful to the late Mr. E. H. Leach and to many others for their help and guidance.