Effect of Parathyroid Extract on Renal Excretion of Phosphate

Publisher Website
Google Scholar
Abstract
The phosphaturia produced in dogs by parathyroid extract has been studied for 3-4 hrs. after administration. Following intraven. injn., marked increases in GFR and RPF rapidly occurred in most animals and, despite a rise in absolute tubular reabsorption, the increased phosphate filtration resulted in a phosphaturia. When calculated as phosphate reabsorbed per 100 ml. of glomerular filtrate, parathyroid extract appeared to inhibit phosphate reabsorption in half the animals studied. Subcut. injn. produced smaller hemodynamic alteration, and a consistent decline in tubular reabsorption accounted for the phosphaturia in each case. An appreciable increase in plasma inorganic phosphate concn. occurred in many dogs after intraven. injection, and contributed to the increased phosphate excretion; this occurred with no change in plasma Ca concn. However, plasma phosphate consistently declined and Ca increased in animals injd. subcut. The difference in behavior of animals treated intraven. and subcut. may be dependent upon the presence of more than one principle in commercial extracts.