RAT BRAIN HISTAMINERGIC NEURONS FOLLOWING SINGLE ETHANOL EXPOSURE: COMPARISON OF LOW AND HIGH DOSE EFFECTS

The central histaminergic system is modulated in neurodegenerative disorders and dementia, as well as in alcoholism since the histamine and ethanol metabolic pathways in the brain share the common enzyme aldehyde dehydrogenase. While numerous biochemical works have reported changes in brain histamine metabolism following ethanol administration, the morphological basis for this action is still missing. In this study we have examined effects of low (1 g/kg) and high, hypnotic (4 g/kg) dose of ethanol on morphological parameters of rat brain histaminergic neurons. We have detected morphometric and histochemical changes compatible with an increase of neuronal activity, confirmed by upregulation of c-Fos in ethanol treated animals, have revealed compensatory and adaptive changes following ethanol administration aimed to support the viability of these neurons in the situation of ethanol intoxication.