title: Quantitative analysis of the sympathetic innervation of the rat knee joint.
abstract: Retrograde tracing with Fluoro-Gold (FG) was used to identify the complete population of knee joint sympathetic postganglionic efferents in the lumbar sympathetic chain of adult female Wistar rats. In 6 rats, the total number and distribution of FG-labelled neurons in the lumbar sympathetic chain was determined. The rat knee joint is supplied by an average of 187+/-57 sympathetic afferents with the majority at the L3 and L4 levels. Immunohistochemistry using antibodies specific for tyrosine hydroxylase (TH), somatostatin (SS) or vasoactive intestinal polypeptide (VIP) revealed that 33 % of knee joint sympathetic afferents contained TH, 42 % contained VIP, and none contained somatostatin. Retrograde tracing with FG provided accurate and reproducible labelling of the joint-innervating subpopulation of sympathetic efferent neurons. This model lends itself to the further study of the molecular responses of this neuronal population in the various disorders and conditions affecting joints.
authors.affiliation: Department of Surgery, University of Toronto, Canada.
authors.forename: M G
authors.initials: MG
authors.lastname: Catre
authors.forename: P T
authors.initials: PT
authors.lastname: Salo
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005121:Extremities; D005260:Female; D007150:Immunohistochemistry; D007596:Joints / Q000294:innervation*; D051381:Rats; D017208:Rats, Wistar; D017779:Sympathetic Fibers, Postganglionic / Q000033:anatomy & histology* / Q000737:chemistry / Q000201:enzymology; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis; D014660:Vasoactive Intestinal Peptide / Q000032:analysis
chemical_list: D014660:Vasoactive Intestinal Peptide; D014446:Tyrosine 3-Monooxygenase