N. Hirasawa et al., INCREASE IN HISTAMINE PRODUCTION BY INFLAMMATORY EXUDATE IN THE CHRONIC PHASE OF ALLERGIC INFLAMMATION IN RATS, Inflammation, 22(5), 1998, pp. 471-482
In the air pouch-type allergic inflammation in rats, we reported that
a sustained histamine production in the late phase is induced by a cyt
okine-like factor, named histamine-production-increasing factor (HPIF)
(1). Recently, we found another type of histamine-production-increasi
ng factor in the pouch fluid at the chronic phase of air pouch-type al
lergic inflammation. Although it did not increase histamine production
by itself, it enhanced the HPIF-induced histamine production by rat b
one marrow cells. It also increased GM-CSF-induced histamine productio
n. The activity of this factor increased time-dependently from 3 to 7
days after the antigen challenge. Injection of the 5 day pouch fluid s
ample containing this factor into the pouch 4 h after the antigen chal
lenge increased histamine contents in the pouch fluid at 24 h, indicat
ing that this factor enhances HPIF-induced histamine production in viv
o. Biochemical analysis of the 5 day pouch fluid sample indicated that
this factor is a heat-labile and trypsin-sensitive protein of which p
i value and molecular weight are 7-8 and about 100 kDa, respectively.