Uptake of radioactive phosphorus in experimental tumors. II. effect of vascularity on radioactive uptake in neoplastic, inflammatory, and normal ocular tissue.

This second phase of the study of "Uptake of Radioactive Phosphorus in Experimental Tumors" deals with the uptake of P32 by malignant tissue, in comparison with that by inflammatory ocular tissue, and an investigation of the influence of vascularity upon the uptake of P32 in normal, inflammatory, and neoplastic tissues. There has been some speculation as to the effect of vascularity upon the uptake of P32by neoplastic as compared with normal tissue. Obviously, with greater vascular supply, the tissue is exposed to more radioactive material and also has a greater capillary area for diffusion of the phosphate ion across the membrane into the tissue itself. Either of these mechanisms may result in higher deposi tion. In curves of radioactive uptake, the initial rapid rise, or that occurring during the first 5 minutes of observation, is thought generally to be due to vascularity (3). Following the pattern set forth in our first paper on uptake of radioactive phosphorus in experimental tumors, the study of the influence of vascularity was approached in three sets of experiments: 1. Inflammatory corneal lesions were produced, and uptake studies were carried out over the lesions and simultaneously over normal ocular tissue, and the pattern of accumulation was plotted againsL the element of time. 2. Perfusion studies were carried out on eyes containing anterior chamber neoplasms. Com parative radioactive counts were made over both the neoplasm and the normal ocular tissue. 3. Comparative measurements of the uptake