Mice with ablation of 5‐HT2B receptors, restricted to the BM, are resistant to NdF‐induced valvulopathy. Reduced mitral valve thickness and endothelial cellularity after chronic NdF administration (1 mg·kg−1·day−1, during 28 days, s.c.) in lethally irradiated mice transplanted with BM cells from Htr
2B
−/− (B: WT_KO_NdF) compared with mice transplanted with WT BM (A: WT_WT_NdF) (scale bar = 200 μm); arrow indicates characteristic valvular lesions. Mitral valve thickness (C), endothelial (D) and interstitial cellularity (E) of transplanted mice exposed to NdF. Values are means ± SEM (n = number of animals per group). *P < 0.05, significantly different from mice transplanted with WT BM; unpaired Student's t‐test.