title: Evidence for a neuropathic contribution to the development of spontaneous knee osteoarthrosis in a mouse model.
abstract: Previous work has shown a progressive, age-related loss of knee joint innervation in the C57BL6Nia mouse. We did three experiments to describe further the loss and determine whether it might contribute to the development of knee osteoarthrosis in this model. Immunocytochemistry showed that the percentage of neurons expressing substance P and calcitonin gene-related peptide increased with age, indicating a relatively selective loss of mechanoreceptors. Histological examination of knee joints of mice at various ages showed that loss of joint innervation always preceded histological changes of cartilage degeneration. The mice usually developed a mild form of osteoarthrosis, but surgical ablation of joint innervation caused the development of severe patellofemoral osteoarthrosis. The findings are consistent with the hypothesis that an age-related loss of joint innervation may contribute to the development of osteoarthrosis.
authors.affiliation: McCaig Centre for Joint Injury, Department of Surgery, University of Calgary, AB, Canada. salo@ucalgary.ca
authors.forename: Paul T
authors.initials: PT
authors.lastname: Salo
authors.forename: Ruth A
authors.initials: RA
authors.lastname: Seeratten
authors.forename: W Mark
authors.initials: WM
authors.lastname: Erwin
authors.forename: Robert C
authors.initials: RC
authors.lastname: Bray
mesh_terms: D000375:Aging / Q000502:physiology; D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis; D004195:Disease Models, Animal; D007150:Immunohistochemistry; D007719:Knee Joint / Q000294:innervation*; D008297:Male; D008465:Mechanoreceptors; D051379:Mice; D008810:Mice, Inbred C57BL; D009479:Neuropeptides / Q000032:analysis; D020370:Osteoarthritis, Knee / Q000209:etiology* / Q000473:pathology*; D018570:Risk Assessment; D012307:Risk Factors; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013373:Substance P / Q000032:analysis
chemical_list: D009479:Neuropeptides; D013373:Substance P; D015740:Calcitonin Gene-Related Peptide