“…Considering the 418 G iertz/G lanzmann/K eller fact that, in the present experiments, blood was collected only 60 min after challenge in most cases, the concentrations of circulating histamine were rather high. The mean concentration of histamine found in the blood of both normal and shocked rats was of the same order as that reported by other workers [2,10,14]. These data were extended by results of histamine levels in animals challenged after pretreatment with compound 48/80; here, plasma histamine concentrations were only slightly increased.…”