Food-associated drinking in pygmy goats: importance of histamine receptors

The combined effect of the histamine receptor antagonists Dexbrompheniramine (DXB: H1-receptor antagonist) and Cimetidine (C: H2-receptor antagonist) on food and water intake was investigated in pygmy goats. DXB (1 mg/kg BW0.75) and C (16 mg/kg BW0.75) were injected together intraperitoneally (i.p.). Cumulative food and water intake, as well as meal and draft pattern, were recorded. DXB and C significantly reduced cumulative water intake, whereas cumulative food intake did not change. Water to food ratio was also significantly diminished. Draft frequency and the percentage of drafts associated with meals were significantly reduced during the 6 h post injection, while meal frequency and meal size did not change during this period. The results show that blockade of the H1- and H2-histamine receptors attenuates the association between water and food intake in pygmy goats. Therefore, mechanisms responsible for meal-associated drinking seem to depend upon activation of histamine receptors.