OBJECTIVETo investigate the preclinical evaluation method of pseudoanaphylactoid reactions for Chinese herbal injections.

METHODBeagle dogs were divided into control group (C), 0.5% tween 80 group (T), Yuxincao injection containing 0.5% tween 80 (YT), distilled solution from Yuxincao (Y). Various groups of Beagle dogs were given 3 mL x kg(-1) of the test articles intravenously. The anaphylactoid reactions were observed immediately, while blood pressure, respiratory frequencies and heart rates were tested at 10 min and 30 min after administration.

RESULTA variety of symptoms that range from cutaneous and mucosa signs to bronchospasma and cardiovascular collapse, including angioedema at lip, conjunctiva, ear and circumoral skin, somnolence, lethargy, breathless or dyspnea, severe hypotension etc were observed in T and TY groups from immediately post-injection to at least 30 min after administration. These reactions occurred at both first injection or repeated injections at 24 weeks intervals, manifesting that it was pseudoanaphylactoid reaction mediated by non-immune mechanisms.

CONCLUSIONBeagle dogs could be used as an animal model for preclinical evaluation of pseudoanaphylactoid reactions of Chinese herbal injection with sensitivity, reproducibility, and high clinic consistency.