Bx dsu microscope

Immunohistochemistry was used to detect changes in morphology and SNAP-25 expression in the posterior and anterior horns of spinal cord after SCI. The primary antibody was mouse anti-SNAP-25 (1:100, monoclonal, Boster). Rats in the SCI and sham groups (n = 3 per group) were anesthetized with 3.6% chloral hydrate and perfused with 4% paraformaldehyde. Briefly, spinal cord tissues were fixed in paraffin. Paraffin sections were cut transversely at 4 μm. After dewaxing and hydration, high-pressure antigen retrieval was performed. The sections were rinsed in 0.05 M phosphate-buffered saline and endogenous enzymes were inactivated by 3% H₂O₂. Before adding the primary antibody, 5% goat serum with 0.3% Triton X-100 was used. Sections were incubated overnight at 4°C with the primary antibody followed by horseradish peroxidase-conjugated goat anti-mouse IgG (1:200; ZSGB-BIO, Beijing, China). Images of the epicenter of the injured spinal cord were photographed using an Olympus BX-DSU microscope (Olympus, Tokyo, Japan). The positive staining was quantified using ImageJ (National Institutes of Health, Bethesda, MD, USA).