Flowcytometric evaluation of the DNA distribution in isolated pancreatic islets from normal and diabetic mice.

Abstract

Pancreatic islets from C57BL/KsJ-db/db, and +/+ mice were isolated by collagenase. After isolation the islets were transferred to a hypotonic ethidiumbromide solution with 0.3% of the detergent Nonidet P40. After vortexing, the samples were analyzed in a BioPhysics Cytofluorograf 4802A. The DNA histograms were divided into 2c, 2-4c, 4c and 8c fractions under the assumption of a constant rate of DNA synthesis during the 2-4c phase. In comparison with normal mice, we found that diabetic mice had a lower fraction of 2c nuclei and a higher fraction of 2-4c, 4c, and 8c nuclei. These results obtained by flow cytometry are in agreement with results obtained by 3HTdR incorporation and by cytophotometry on histological sections.

Polyploid cells in the mouse ovary

“…The results for the control tissues agree with previous findings obtained by other methods in showing a higher frequency of polyploid nuclei in the liver (Epstein, 1967; Brodsky & Uryvaeva, 1977, 1985) than in the pancreas (Larsen & Nielsen, 1978; Webb et al. 1982; Ornitz et al.…”

Cell Cycle Analysis of the Postnatal Mouse Pancreas

“…Extension of DNA flow analysis to the individually iso lated components of the pancreas from nor mal and diabetics subjects may provide a better understanding of the detection and progression of the disease. One report by Larsen and Nielsen [12] documents that DNA analysis using flow microfluorometry of islet cells from normal and diabetic mice is a feasible alternative to established proce dures for characterization of cellular DNA(ploidy) and proliferation. A prerequi site to interpretation of data on the progres sion of polyploidy in diabetes is, of course, first, a thorough understanding of all aspects of cell cyle changes in the normal pancreas.…”

Growth and Function of the Pancreatic β cell in vitro

“…Such studies require long-term culture of the islets. In long-term culture simple microscopic examination of the islet size or meas¬ urement of DNA content in the islets are more reliable expressions of the cell mass (V) although a minor frequency of polyploidy among the islet cells may occur (Larsen & Nielsen 1979). A widely used method is the measurement of incorporation of 3H-thymidine into DNA.…”