Radioactive Colloidal Gold in Macrophages and Serous Exudate in Peritoneal Fluid of Sarcoma Bearing Mouse.

Abstract

CFW and dba mice were inoculated intraperit. with Sarcoma 37 cells from serial intraperit. transfers. After formation of copious peritoneal exudate containing tumor cells and macrophages, these mice received intraperit. or intraven. 0.1 mc (in 2 series, 0.3 mc) of radioactive colloidal gold. At various intervals (30 min. to 48 hrs.) after injn., specimens of peritoneal fluid were withdrawn from these mice and centrifuged. Radioactivity of precipitate (P) and of supernatant (S) in each specimen was detd. by Geiger counter. Ratio P/S was accepted as index of radioactivity distr. between macrophages and serous exudate of the peritoneal fluid. Data illustrating trends in changes of P/S in various groups of mice were plotted in graphs and discussed. These data were interpreted as the combined effect of 2 parallel phenomena responsible for disappearance of radioactive colloid from the peritoneal serous exudate: [long dash]Absorption and storage of colloid particles into macrophages; and their diffusion into circulating blood. The ratio P/S in various specimens of peritoneal fluid from the same mouse remained consistently on higher levels after the use of higher doses of radioactive colloidal gold; the use of dba mice, and the prepn. with inactive (decayed) colloidal gold before treatment with radioactive gold. The effect of these factors is attributed to the increase in the number and in the activity of macrophages.