Immunocytochemical analysis of the Ki67 expression and BrdU incorporation in ARPE-19 cells.

<p>Immunocytochemical analysis of the Ki67 expression in ARPE-19 cells after 24 h of proliferation. A) Control. B) 10% FBS (v/v). C) 100 nM human obestatin (<b>1</b>). D) 100 nM human non-amidated obestatin (<b>2</b>). E) 100 nM human (6–23)-obestatin (<b>3</b>). F) 100 nM human (11–23)-obestatin (<b>4</b>). G) 100 nM human (16–23)-obestatin (<b>5</b>). H) 100 nM mouse obestatin (<b>6</b>). The magnification was 20x. I) Quantification of the immunocytochemical expression of Ki67 in ARPE-19 cells after treatment with 10% FBS (v/v; 100±2), 100 nM human obestatin (<b>1</b>; 84±1%), 100 nM human non-amidated obestatin (<b>2</b>; 33±2%), 100 nM human (6–23)-obestatin (<b>3</b>; 56±3%), 100 nM human (11–23)-obestatin (<b>4</b>; 67±3%), 100 nM human (16–23)-obestatin (<b>5</b>; 50±2%) and 100 nM mouse obestatin (<b>6</b>; 32±2%). The expression of Ki67 was expressed as the fold change relative to the expression level in FBS-treated cells in the positive control (mean ± SE). J) BrdU incorporation in ARPE-19 cells after treatment with 10% FBS (v/v; 100±1), 100 nM human obestatin (<b>1</b>; 84±4%), 100 nM human non-amidated obestatin (<b>2</b>; 39±2%), 100 nM human (6–23)-obestatin (<b>3</b>; 30±1%), 100 nM human (11–23)-obestatin (<b>4</b>; 52±3%), 100 nM human (16–23)-obestatin (<b>5</b>; 34±3%) and 100 nM mouse obestatin (<b>6</b>; 35±1%). The BrdU incorporation was expressed as the fold change relative to the level in FBS-treated cells in the positive control (mean ± SE). The data are expressed as the mean ± SE. The asterisk (*) denotes <i>P</i><0.05 when comparing the peptide-treated ARPE-19 cells groups with the human obestatin (<b>1</b>)-treated group.