Effect of deoxynivalenol on neurotransmitters in discrete regions of swine brain.

The effect of deoxynivalenol (DON, vomitoxin) on brain amine levels was investigated in swine. DON, a trichothecene mycotoxin, causes suppression of feed intake (anorexia) in susceptible species. Following acute administration of DON to pigs (0.25 mg/kg, IV), concentrations of endogenous catecholamines norepinephrine (NE), dopamine (DA), 3,4-dihydroxyphenyl-acetic acid (DOPAC), and homovanillic acid (HVA), and the indoleamines, 5-hydroxytryptamine (5HT, serotonin) and 5-hydroxyindoleacetic acid (5HIAA) were determined in five brain regions, periodically during the 24 h post-dosing. Analysis was carried out by high performance liquid chromatography, using electrochemical detection. Effects of DON in the swine brain were transmitter, time and region-specific. It was observed that levels of the major transmitters (NE, DA and 5HT) were statistically different from controls in the hypothalamus (Hypo), frontal cortex (FCX) and cerebellum (Cb) up to 8 h post-dosing. Overall, DON administration elevated NE and depressed DA concentrations in these regions, and levels of 5HT which increased initially in Hypo (1 h), had dropped significantly below controls in both Hypo and FCX at 8 h. These alterations, however, were not indicative of known neurochemical changes associated with chemical-induced anorexia. Instead, this data suggested that the neurochemical effects of acute DON exposure might be due to peripheral toxicological events (i.e., vomiting), which overwhelmed its more subtle feed refusal activity.