title: Inhibiting effect of plasma from normal and tumour bearing mice on the mitotic rate of regenerating liver.
abstract: Plasma from normal mice and from mice bearing the ES2 transplantable malignant tumour was injected intraperitoneally at a dose of 0.01 ml/g body weight in partially hepatectomized mice. Control animals were injected with a solution of sodium citrate in saline. The recipients were killed at the first (14:00 hours/48 h). These times are the time of day and the number of h after partial hepatectomy and second (14:00 hours/72 h) peak times after partial hepatectomy. The number of colchicine metaphases per 1000 nuclei was determined for hepatocytes and litoral cells. A different effect was obtained with plasma from tumour-bearing compared with normal mice. Plasma from both sources when injected 26 h after partial hepatectomy (16:00 hours/26 h) inhibited the mitotic activity of hepatocytes at the next peak of regenerative activity (14:00 hours/48 h). The plasma from tumour-bearing mice also inhibited the peak on the following day (14:00 hours/72 h), whereas plasma from normal mice had no inhibitory effect and, indeed, a compensatory wave was observed at this time. Furthermore, plasma from tumour-bearing mice also showed an inhibitory effect at the first peak (14:00 hours/48 h) when injected at the time of partial hepatectomy (14:00 hours/00 h) or at 22 h before partial hepatectomy (16:00 hours/-22 h) whereas the injection of plasma from normal mice at these times had no inhibitory effect. In the litoral cells the injection of plasma from tumour-bearing mice made 22 h before hepatectomy (16:00 hours/-22 h) led to a stimulation of mitotic activity which was controlled at 14:00 hours/48 h.(ABSTRACT TRUNCATED AT 250 WORDS)
mesh_terms: D000818:Animals; D001769:Blood; D002940:Circadian Rhythm; D006498:Hepatectomy; D007267:Injections; D008099:Liver / Q000166:cytology; D008115:Liver Regeneration; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D008938:Mitosis; D008940:Mitotic Index; D009374:Neoplasms, Experimental / Q000097:blood*