Species-Differences in the Process of Apoptosis in Epithelial Cells of the Small Intestine. An Ultrastructural and Cytochemical Study of Luminal Cell Elements

Abstract

The kinetics of rat macrophage proliferation in the inflamed pancreas was analysed using a duct-ligation pancreatitis model. We performed a dou-ble immunostaining of pancreatic cryosections using a panel of monoclonal antibodies to either macrophage-specific (EDI, ED2) or macrophage-related (CR3 and la) antigens in combination with a cell marker of DNA synthesis (5-bromo-2'-deoxyuridine, BrdU). One hour labeling with BrdU revealed each recorded macrophage phenotype to have a very high labeling index (12-28%), peaking on day 2 after induction of pancreatitis. The percentage of cach proliferating phenotype also reach-ed 20-40% of the total BrdU+ cells on day 2. The prolifer-ating macrophages consisted of heterogeneous subpopu-lations including monocyte-like cells and resident macro-phages. Their growth occurred in a relatively synchron-ized fashion, and seemed to be triggered by common proliferative signals. © 1993, International Society of Histology and Cytology. All rights reserved.