Notch1 deletion does not alter PanIN development following acute pancreatitis.

<p>(<b>A</b>) Schematic of experimental design. Mice were treated with tamoxifen at 8 weeks of age to activate <i>K-ras^G12D</i> and delete <i>Notch1</i> expression. Two weeks later, mice were treated with caerulein for 2 consecutive days to induce acute pancreatitis. Pancreatic tissue was collected 3 weeks following the final caerulein treatment. (<b>B</b>) Histological analysis of pancreas tissue from <i>Elastase1-Cre^ERT2;Notch1^lox/lox</i>, <i>Elastase1-Cre^ERT2;Kras^G12D</i>, and <i>Elastase1-Cre^ERT2;Kras^G12D;Notch1^lox/lox</i> mice following acute pancreatitis. PanIN-3 lesions are shown in <i>Elastase1-Cre^ERT2;Kras^G12D</i> and <i>Elastase1-Cre^ERT2;Kras^G12D;Notch1^lox/lox</i> pancreas tissue. Scale bar, 30 µm. (<b>C</b>) Fibroplasia and inflammation observed in <i>Elastase1-Cre^ERT2;Kras^G12D</i> and <i>Elastase1-Cre^ERT2;Kras^G12D;Notch1^lox/lox</i> pancreas tissue. Scale bar, 100 µm. (<b>D</b>) Atypical flat lesions (AFLs) were observed in <i>Elastase1-Cre^ERT2;Kras^G12D</i> and <i>Elastase1-Cre^ERT2;Kras^G12D;Notch1^lox/lox</i> pancreas tissue. Scale bar, 100 µm. (<b>E</b>) Analysis of the number of PanIN lesions found per pancreas in <i>Elastase1-Cre^ERT2;Kras^G12D</i> (n = 5) and <i>Elastase1-Cre^ERT2;Kras^G12D;Notch1^lox/lox</i> (n = 6) following acute pancreatitis.