The acute effect of ethanol on behaviour, body temperature, and brain histamine in mice.

The possible relationships between ethanol-induced changes in behaviour, body temperature, and brain histamine were studied. Mice were injected intraperitoneally with various doses of ethanol in the range of 0.088--1.75 g/kg. There was a dose-dependent biphasic alteration in behaviour and body temperature, where a low dose of 0.175 g/kg produced excitation and hyperthermia. Doses of 0.875 and 1.75 g/kg caused an increasing state of depression and dose-dependent hypothermia. Behavioural changes induced by ethanol appear to reflect changes in body temperature. When hyperthermia was produced the animals were hyperactive, whereas with hypothermia they were sedated and huddled close together. These changes in behaviour and body temperature closely paralleled the ethanol-induced modifications in whole brain histamine levels, indicating that a relationship may exist between the ethanol-induced changes in these parameters.