Toluidine blue staining of articular cartilage from saline (a, c) and MIA (b, d) injected ipsilateral knee joints. Smooth and intact articular surface of the femur and tibia from 3-month (a) and 22-month (c)-old mice injected with saline in contrast to thinning and loss of articular integrity (indicated by arrows) in 3-month (b) and 22-month (d)-old mice injected with 1-mg MIA. Scale bar = 500 μm. Development of monosodium acetate-induced osteoarthritis and inflammatory pain in ageing mice: Ogbonna AC, Clark AK, Malcangio M - Age (Dordrecht, Netherlands) (2015). Not altered. CC.