Histological and immunohistochemical analysis of the effects of BaP1 and leuc-a in skeletal muscle.

<p>Mice were injected with either 50 µL PBS as control (A, D), 50 µg of leuc-a (B, E) or 50 µg BaP1 (C, F). Tissue samples were collected 15 min after injection and processed for embedding in paraffin (see experimental details in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0028017#s2" target="_blank">Methods</a>). A, B and C: Hematoxylin-eosin staining. Hemorrhage, evidenced by the presence of erythrocytes in the interstitial space (arrows), occurred only in muscle injected with BaP1. D, E and F: Immunostaining with anti-type IV collagen (green) and anti-VEGFR2 (red). Arrows depict capillary vessels. There is a reduction in capillary vessels positive for type IV collagen and VEGFR2 in samples treated with BaP1, whereas no reduction in the staining of capillaries was observed in tissue injected with leuc-a. Bar corresponds to 50 µm. (G) The total number of capillaries and muscle cells were counted in various sections, and the capillary: muscle cell ratio was calculated. Results are presented as mean ± SD. A significant reduction in the ratio was observed only in muscle injected with BaP1, but not with leuc-a. *<i>P</i><0.05 when compared with capillary: muscle cell ratios of control and leuc-a-treated samples.