Histamine and its catabolism in tumour-bearing rat and mouse.

The hypothesis that failure of histamine (Hi)-mediated inter and intracellular cell-cell communication may be involved in the control of cellular growth has been tested in leukaemia-bearing mice and fibrosarcoma-bearing rats. In all examined tissues of mice bearing leukaemia L1210 cells and rats bearing methylcholanthrene fibrosarcoma histamine content was higher than in controls. Tissues of fibrosarcoma-bearing rats more intensively metabolized 14C-Hi and oxidative pathway was predominant. Histamine metabolic activity as well as histamine catabolic pathways do not differ in leukaemic mice as compared with the controls.