title: Toxic effects of mercuric sulfide on immune organs in mice.
abstract: Mercuric sulfide (HgS) is a major component of cinnabar, which has been used as a sedative drug in China for more than 2000 years. Because its toxicological effects are still unclear, we attempted to verify the toxic effects of HgS, focused on liver and immune organs such as the spleen and thymus. Male ICR mice were administered HgS (0.02, 0.2, 2.0 g/kg/day) by gavage for 4 weeks. During the administration period, HgS-treated mice did not reveal overt signs of clinical toxicity. HgS had no significant effect on body weight, food consumption, water consumption, and organ weights. In spite of its known insolubility, HgS was absorbed by the gastrointestinal tract and accumulated in the liver, spleen and thymus in a dose-dependent manner. In the biochemical and histological examination, HgS did not cause hepatotoxicity. However, HgS significantly increased both CD8(+) T lymphocytes and CD4(+)CD8(+) lymphocyte populations in the spleen without changing in the thymus. In the histological evaluation, HgS induced enlargement with marked hyperplasia and increase of lymphoid follicles in the spleen. In addition, HgS induced the gene expression of pro-inflammatory cytokines in the spleen and thymus. Our results suggest that insoluble HgS was absorbed by the gastrointestinal tract, accumulated in the spleen and thymus, and thus could affect immune systems.
authors.affiliation: Cell and Matrix Research Institute, Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu, Republic of Korea.
authors.forename: Hee-Young
authors.initials: HY
authors.lastname: Son
authors.forename: Soyoung
authors.initials: S
authors.lastname: Lee
authors.forename: Seung-Bin
authors.initials: SB
authors.lastname: Park
authors.forename: Mi-Sun
authors.initials: MS
authors.lastname: Kim
authors.forename: Eun-Ju
authors.initials: EJ
authors.lastname: Choi
authors.forename: Thoudam S K
authors.initials: TS
authors.lastname: Singh
authors.forename: Yunju
authors.initials: Y
authors.lastname: Bae
authors.forename: Seung Jun
authors.initials: SJ
authors.lastname: Kwack
authors.forename: Tae Seok
authors.initials: TS
authors.lastname: Kang
authors.forename: Hong-In
authors.initials: HI
authors.lastname: Shin
authors.forename: Moon-Chang
authors.initials: MC
authors.lastname: Baek
authors.forename: Sang-Hyun
authors.initials: SH
authors.lastname: Kim
mesh_terms: D000284:Administration, Oral; D000818:Animals; D056486:Chemical and Drug Induced Liver Injury / Q000209:etiology / Q000276:immunology / Q000473:pathology; D016207:Cytokines / Q000235:genetics / Q000276:immunology; D041981:Gastrointestinal Tract / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D022781:Hepatocytes / Q000187:drug effects / Q000473:pathology; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D008111:Liver Function Tests; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology; D008297:Male; D017669:Mercury Compounds / Q000493:pharmacokinetics / Q000633:toxicity*; D051379:Mice; D008813:Mice, Inbred ICR; D009929:Organ Size / Q000187:drug effects; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013154:Spleen / Q000187:drug effects* / Q000276:immunology / Q000473:pathology; D013950:Thymus Gland / Q000187:drug effects* / Q000276:immunology / Q000473:pathology; D014018:Tissue Distribution
chemical_list: D016207:Cytokines; D017669:Mercury Compounds; C034211:cinnabar