Abstract
The quantity of histamine and the number of mast cells in the skin of the pika were measured and compared with rabbits, guinea pigs and rats. The ranking of regional histamine levels in the skin of the pika was : perianal region>abdomen> interscapular region=back>lumbus>head>auricle, and the average value of the 7 regions was 22.6μg/g. The level of histamine in the 6 regions, except the auricle, was 2 - 5 timesthat of rabbits and guinea pigs. In the auricle of each of the 4 kinds of animal (pika, rabbit, guinea pig and rat), the levels were almost identical. With respect to histamine levels, those in the pika resembled those in rats. The number of mast cells in the skin of the pika was less than in rats, and was greater than that in rabbits and guinea pigs. The average value was 9.9/mm2.