Study of bioassayable somatomedin on renal artery and vein.

Somatomedin was measured by rat bioassay in samples obtained from renal artery and vein, in order to study the role of this organ in the production of somatomedin activity. The results showed a significant difference, with an increase of the activity in the venous samples. According to the data reported in the literature with bioassay (low values) and radioreceptor assay (normal or high values) in nephropathic subjects, our results seem to suggest that the kidney mainly inactivates a specific somatomedin inhibitor.