Hypothalamic histamine modulates adaptive behavior of rats at high environmental temperature

Abstract
Histamine content in the rat hypothalamus was lower at 4°C and higher at 31°C compared to that at 21°C. Pretreatment with α-fluoromethylhistidine, a ‘suicide’ inhibitor of histidine decarboxylase, attenuated both the increased level of hypothalamic histamine and rat adaptive behavior at 31°C. Increase of histamine content in the hypothalamus appears to be an important factor contributing to rat adaptive behavior to high environmental temperature.