Increased Levels of ER Stress and Apoptosis in a Sheep Model for Pulmonary Fibrosis Are Alleviated by In Vivo Blockade of the KCa3.1 Ion Channel

Figure 1

Schematic diagram of bleomycin infusion protocols in sheep (n = 8) and immunohistochemical staining against GRP78 to identify ER stressed type II AECs and macrophages in sheep parenchymal lung tissues. (a) In individual sheep (n = 8), the left caudal lung segment received infusions of bleomycin, while the right caudal lung segment received saline for internal control purposes. (b) Diagram shows the timeline for bleomycin/saline infusions and the tissue collections. These infusions were repeated at day 14 and tissue samples were harvested at day 28. All the animals were kept for 14 days acclimation period (pre-treatment) prior to bleomycin/saline administration. (c) Representative images of GRP78 immuno-stained sections taken from the differentially treated lung segments. Arrows indicate ER stressed type II alveolar epithelial cells (AECs) and macrophages (M). (d, e) Graphs represent the number of ER stressed type II AECs and macrophages in bleomycin- (BLM-) and saline-infused lung segments (n = 8 sheep). The data was taken from twenty representative, non-overlapping fields randomly captured under 40x magnification. Each bar represents the mean ± standard error of the mean. Significance was determined by t-test. and .

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