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Biomedical subjects

A B Morrison

Publications and source records attributed to A B Morrison.

At least 55 records · Page 3Linked to original sources
PubMed1973

Vascular permeability of the renal medullary vessels in the mouse and rat.

The vascular permeability of the vessels of the renal medulla of normal rats and mice and potassium-deficient rats was studied by using ferritin, horseradish peroxidase and carbon particles as markers. Fenestrated endothelia are more permeable to ferritin and horseradish peroxidase than nonfenestrated endothelia. The ease with which the tracers are able to pass from the vascular lumina through the endothelia into the interstitium is directly related to the size of the tracers (horseradish peroxidase permeates most readily, followed by ferritin and carbon particles, in this order), suggesting the presence of a molecular sieving mechanism for the passage of substances through the capillary walls of the renal medulla. At the initial stage after injection of horseradish peroxidase and ferritin, these tracers pass from the medullary vascular lumina into the interstitium, not from the tubular lumina into the interstitium. It appears that the passage of ferritin and horseradish peroxidase through the vascular wall is enhanced in potassium-deficient rats.

Animals↗
PubMed1966

The functional capacity of hypertrophied nephrons. Effect of partial nephrectomy on the clearance of inulin and PAH in the rat.

A method is described for the measurement of inulin and PAH clearances in rats without killing the animal. Inulin clearance measurements of partially nephrectomized rats and sham-control rats were made before operation and at intervals following the operation; inulin clearances were determined on normal rats at intervals during their growth. In another series of partially nephrectomized rats and their sham-operated controls, inulin and PAH clearances were determined in all the animals before and at intervals following the operation. Glomerular counts were made in some rats. After partial nephrectomy the inulin clearance is reduced but not as much as would be expected considering the amount of renal tissue removed. The mean inulin clearance per nephron is greatly increased in the partially nephrectomized rat when compared to the value determined for the control rat. The inulin clearance of the partially nephrectomized rat shows a progressive decline which is first clearly evident about 6 months after operation. The sham-operated rats showed an inulin clearance slightly less than that of nonoperated controls about 24 to 30 wk after the operation. In the normal rats the inulin clearance relative to body weight is much greater in rats with a mean weight of 197 +/- 3 g than in normals which are older and heavier. The PAH dearance of the partially nephrectomized rat is reduced following operation but undergoes no further change in the ensuing 24 wk.

Aminohippuric Acids↗