Canine model of ischemic stroke with permanent middle cerebral artery occlusion: clinical features, magnetic resonance imaging, histopathology, and immunohistochemistry

The purpose of this study was to identify time-related changes in clinical, MRI, histopathologic, and immunohistochemical findings associated with ischemic stroke in dogs. Additionally, the association of cerebrospinal fluid (CSF) and tissue levels of interleukin (IL)-6 with clinical prognosis was assessed. Ischemic stroke was induced by permanent middle cerebral artery occlusion (MCAO) in nine healthy experimental dogs. The dogs were divided into three groups according to survival time and duration of the experimental period: group A (survived only 1 day), group B (1-week experimental period), and group C (2-week experimental period). Neurologic status was evaluated daily. Magnetic resonance imaging (MRI) was performed according to a predetermined schedule. Concentration of IL-6 in CSF was measured serially after ischemic stroke. Postmortem examination was performed for all experimental dogs. During histopathological examination, variable degrees of cavitation and necrosis due to neuronal cytopathic effects, such as pyknotic nuclei and cytoplasmic shrinkage, were observed on the affected side of the cerebral cortex in all dogs. Immunohistochemistry specific for IL-6 showed increased expression in the ischemic lesions. CSF IL-6 concentrations and ischemic lesion volumes 1 day after ischemic stroke were significantly higher in group A compared to groups B and C.

A study of experimental autoimmune encephalomyelitis in dogs as a disease model for canine necrotizing encephalitis

In the present study, the use of dogs with experimental autoimmune encephalomyelitis (EAE) as a disease model for necrotizing encephalitis (NE) was assessed. Twelve healthy dogs were included in this study. Canine forebrain tissues (8 g), including white and grey matter, were homogenized with 4 mL of phosphate-buffered saline for 5 min in an ice bath. The suspension was emulsified with the same volume of Freund's complete adjuvant containing 1 mg/mL of killed Mycobacterium tuberculosis H37Ra. Under sedation, each dog was injected subcutaneously with canine brain homogenate at four sites: two in the inguinal and two in the axillary regions. A second injection (booster) was administered to all the dogs using the same procedure 7 days after the first injection. Clinical assessment, magnetic resonance imaging, cerebrospinal fluid analyses, necropsies, and histopathological and immunohistochemical examinations were performed for the dogs with EAE. Out of the 12 animals, seven (58%) developed clinically manifest EAE at various times after immunization. Characteristics of canine EAE models were very similar to canine NE, suggesting that canine EAE can be a disease model for NE in dogs.

Hematologic and hemodynamic findings during hemodialysis in 13 beagle dogs / 동물의과학연구지

Hemodialysis is an effective therapy for renal failure in veterinary practice. To evaluate hematologic and hemodynamic changes during hemodialysis, 13 dogs were treated with hemodialysis, after which complete blood cell counts (CBC), serum chemistry, and mean systolic blood pressure were analyzed. For CBC, white blood cells (WBC) and platelets underwent significant changes. In serum chemistry, there were significant differences in blood urea nitrogen (BUN), creatinine, total protein, albumin, globulin, amylase, calcium, potassium, and phosphorus contents. Further, mean systolic blood pressure suddenly increased in early hemodialysis and decreased significantly thereafter. During hemodialysis, adverse effects were observed in some dogs as follows: bleeding (1 dog), anemia (2 dogs), leukopenia (8 dogs), thrombocytopenia (2 dogs), and hypotension (1 dog). This study demonstrates hematologic and hemodynamic effects during hemodialysis as well as complications similar to human medicine. Before applying the commercialized human hemodialysis system to canine renal failure patients, we monitored hematologic and hemodynamic findings during hemodialysis in healthy beagle dogs.