Inflammatory
cytokines are potential modulators of
infarct progression in acute
ischaemic stroke, and are therefore possible targets for future treatment strategies.
Cytokine studies in animal models of surgically induced
stroke may, however, be influenced by the fact that the surgical intervention itself contributes towards the
cytokine response. Community-dwelling domestic dogs suffer from spontaneous
ischaemic stroke, and therefore, offer the opportunity to study the
cytokine response in a noninvasive set-up. The aims of this study were to investigate
cytokine concentrations in plasma and cerebrospinal fluid (CSF) in dogs with acute
ischaemic stroke and to search for correlations between
infarct volume and
cytokine concentrations. Blood and CSF were collected from dogs less than 72 h after a spontaneous
ischaemic stroke.
Infarct volumes were estimated on MRIs.
Interleukin (IL)-2,
IL-6,
IL-8,
IL-10 and tumour
necrosis factor in the plasma, CSF and brain homogenates were measured using a canine-specific multiplex immunoassay.
IL-6 was significantly increased in plasma (P=0.04) and CSF (P=0.04) in
stroke dogs compared with healthy controls. The concentrations of other
cytokines, such as tumour
necrosis factor and
IL-2, were unchanged. Plasma
IL-8 levels correlated significantly with
infarct volume (Spearman's r=0.8, P=0.013). The findings showed increased concentrations of
IL-6 in the plasma and CSF of dogs with acute
ischaemic stroke comparable to humans. We believe that dogs with spontaneous
stroke offer a unique, noninvasive means of studying the inflammatory processes that accompany
stroke while reducing confounds that are unavoidable in experimental models.