The measurement of histamine release from suspensions of rat peritoneal cells rich in mast cells.

Histamine released from the mast cells in unfractionated rat peritoneal cell suspensions could be quickly and conveniently measured by an automated chemical method. There were no substances in the unfractionated peritoneal cells that interfered with the chemical histamine measurement. Organic extraction of histamine and deproteinization of samples were not necessary using the automated method. The amount of histamine released from preparations of peritoneal cells by a fixed concentration of compound 48/80 decreased with the time of preincubation of the cells but this varied between preparations. Phagocytic activity directed against the mast cells probably explained these observations. The state of nutrition of the rats and the presence or absence and/or glucose in the medium all influenced the rate of decline of viability of the mast cells.