OBJECTIVETo investigate the sensitizing potential of Shuanghuanglian Injection (SHL) by comparing the popliteal lymph node (PLN) response in mice induced by SHL and chemicals.

METHODSSixty female C57BL/6J mice were equally and randomly divided into six groups, i.e. the blank control group (A) and five treated groups treated respectively with phenobarbital 1 mg/mouse (B), mercuric chloride ( HgCl2) 50 microg/mouse (C), D-penicillamine 2 mg/mouse (D), and SHL in low (1 mg/mouse) and high (5 mg/mouse) dosages (E and F) via subcutaneous injection into left pad of hind foot. Animals were sacrificed on the 8th day after injection, their bilateral PLNs were isolated and weighed respectively to calculate the PLN mass index (MI). Then the PLNs get from four mice in each group were fixed with 4% paraformaldehyde solution for histopathologic examination; the other six PLNs were prepared into single-cell suspensions to calculate cell index (CI) for comparing the changes of PLN in various groups.

RESULTSMI and CI in Group F reached to > or = 2 and > or = 5 (average) respectively, which was higher than those in Group A (P<0.05). Pathological examination showed that the left PLN in Group F enlarged, with remarkable germinal center and increased high endothelial venules proliferation.

CONCLUSIONSHL could induce significant PLN response in C57BL/6J mice, suggesting it has certain sensitizing potential.