Introduction: Histamine is one of the most important mediators in the mammalian organism. It has a basic role in numerous physiological fuctions and also in the regulation of cell growth. Material and methods: In the present study the level of cell-bound and secreted histamine was measured in rats exposed to histamine in vivo during their neonatal age or in controls. Results and main conclusions: The findings strongly suggest that the in vivo treatment of neonatal rats with histamine leads to significantly increased level of both spontaneous and histamine-provoked histamine secretion at the age of two months. The results suggest a long-lasting effect of neonatal histamine treatment.

Keywords: Histamine, peritoneal cells, neonatal effects