Subject(s)
Catecholamines/metabolism , Horses/metabolism , Hydrocortisone/blood , Peptides/analysis , Pituitary Gland/metabolism , Adrenocorticotropic Hormone/blood , Adrenocorticotropic Hormone/cerebrospinal fluid , Animals , Arginine Vasopressin/blood , Arginine Vasopressin/cerebrospinal fluid , Catecholamines/blood , Catecholamines/cerebrospinal fluid , Catheterization/veterinary , Chromatography, High Pressure Liquid/veterinary , Dopamine/blood , Dopamine/cerebrospinal fluid , Dynorphins/blood , Dynorphins/cerebrospinal fluid , Enkephalin, Methionine/blood , Enkephalin, Methionine/cerebrospinal fluid , Female , Horses/blood , Horses/cerebrospinal fluid , Male , Norepinephrine/blood , Norepinephrine/cerebrospinal fluid , Peptides/blood , Peptides/cerebrospinal fluid , Radioimmunoassay/veterinary , Reference Values , beta-Endorphin/blood , beta-Endorphin/cerebrospinal fluidABSTRACT
Forty-five horses were infected peripherally or intrathecally with enzootic or epizootic strains of Venezuelan equine encephalomyelitis (VEE) virus. Low titers of virus appeared in cerebrospinal fluid (CSF) after peripheral inoculation of enzootic or epizootic VEE virus strains. Intrathecal infection with either epizootic or enzootic VEE virus produced higher titers of virus in CSF than did peripheral infection. In contrast to peripheral infections with enzootic strains, intrathecal infections with these strains caused death. The animals that died had widespread histopathologic changes and large amounts of virus in brain tissue. The attenuated VEE virus vaccine strain, TC-83, also multiplied in the brain of horses inoculated intrathecally but caused no clinical disease and little histopathologic damage.