The correlations between blood flow or glucose metabolism and distribution of DNA synthesizing cells were simultaneously investigated in the same rat brain tumors using autoradiographic technique and immunoperoxidase stain. Two rat brain tumor strains (A and B) induced by Rous sarcoma virus were used. A suspension of 1 X 10(4) rat brain tumor cells was stereotactically implanted into the right basal ganglia of syngenic Fischer 344/Du Crj rats. The tumor strain A bearing rats died 12.0 +/- 1.8 days and the tumor strain B bearing rats died 17.6 +/- 1.3 days after the tumor implantation. Blood flow and glucose metabolism were measured with 14C-iodoantipyrine and 14C-2-deoxy-D-glucose autoradiography. All rats also received a 1-h i.v. infusion of BrdU, 5-20 mg, at the autoradiographic procedure. The immunoperoxidase staining for BrdU (Avidin Biotin peroxidase complex method) and other conventional stainings were performed in the sections alternating with the autoradiographic sections. BrdU-positive nuclei (S-phase cells) were heterogeneously distributed and labeling index ranged from less than 1% to more than 40% in the tumors. Neoplastic vessels tended to be distributed in the peripheral part of the tumor and were surrounded with S-phase cells in a part of the tumor. The blood flow was heterogeneously distributed in the tumor and the average blood flow reduced to about 50% in the tumor strain A and to about 60% in the tumor strain B, respectively in comparison with contralateral cortex. The distribution of blood flow did not correlate with the distribution of S-phase cells nor the distribution of neoplastic vessels.(ABSTRACT TRUNCATED AT 250 WORDS)