Effects of treatments with MTX alone or with supplementary folinic acid (FA) for 6 weeks on growth plate chondrocyte apoptosis.

<p><i>In Situ</i> TUNEL labeling of growth plate apoptotic chondrocytes from week 6 control (A), MTX-treated (B), and MTX+FA (C) treated rats, with arrows pointing to TUNEL positive apoptotic chondrocytes, characterized by fragmented nuclei (enlarged version shown in dotted square). (D) Treatment effects on density of apoptotic chondrocytes in growth plate. (E, F) Treatment effects on mRNA expression of apoptotic death receptor pathway genes Fas and Fas-L relative to Cyclophilin-A. Scale bar on panels A–C = 200 µm.