No abstract

No abstract

(1) Antigen, in sensitized guinea pigs, produced a dose-dependent increase of the serum adrenaline concentrations, whereas the noradrenaline levels were not enhanced significantly. (2) The anaphylactic adrenaline release was diminished, but not prevented, by high doses of the antihistamine mepyramine. (3) Rat serum anaphylatoxin, in non-sensitized animals, provoked a significant increase in both the adrenaline and noradrenaline concentrations. Mepyramine abolished the adrenaline release, but not the noradrenaline release. (4) Histamine, in non-sensitized guinea pigs, also caused a dose-dependent adrenaline release, which was partially resistant to mepyramine.