| Objective:Zhu Hong ointment iscomprised of cinnabar,hydrargyri oxydum rubrum and vaseline.It has the effect of removing the necrotic tissue and promoting granulation.After decades of clinical use,it has significant effects in the treatment of chronic skin ulcers.However,because the cinnabar and the hydrargyri oxydum rubrum are all mercury-containing mineral medicines,the safety of clinical use has received widespread attention.Although the toxicity and toxicity mechanism of mercury-containing mineral drugs have made great progress,the types and forms of mercury-containing toxic components that are transdermally absorbed into the body remain unclear.This project mainly studied the types of toxic components in Zhu Hong Ointment,and analyzed the types and forms of mercury absorbed into the body by HPLC-ICP-MS method.At the same time,its accumulation in the liver,kidney,and brain and its toxic effects on the liver and kidneys were discussed.In order to scientifically evaluate the transdermal absorption and toxicity of Zhu Hong ointment and provide a certain reference for clinical application.Methods:1.Based on literature research,preliminary definition of the possible indicators related to toxicity in Zhu Hong ointment.Basing on the determination method of cinnabar in the Chinese Pharmacopoeia,the total mercury content in Zhu Hong ointment,as well as the content of HgS and HgO were determined.HPLC-ICP-MS method used to determine the content of organic mercury in Zhu Hong ointment.At the same time,the contents of soluble mercury salts in Zhu Hong ointment and other soluble toxic heavy metals such as lead,arsenic,and cadmium were detected.2.HPLC-ICP-MS method used to detect the form of transdermal mercury.Different degrees of rat skin models were established by combining the actual skin conditions of clinical patients.The skin transdermal absorption and transdermal absorption rate of mercury in Zhu Hong ointment were measured for different degrees of skin damage using Franz diffusion cell.3.In this study,a skin injury model of rat was established to study the in vivo transdermal absorption of Zhu Hong ointment.Mercury species in major target organs after 4 weeks of administration in rats were determined.Rats were given different doses of Zhu Hong ointment.After 4 weeks,the levels of mercury in blood,urine,liver,kidney and brain,and the contents of ALT,AST,BUN and Cr in serum,and BMG and NAG in urine were measured.The liver and kidney of rats were observed for histomorphology,and the accumulation of mercury in the main target organs and the toxic effects on liver and kidney were investigated.Results:1.The mercury content in Zhu Hong ointment was 16.95%,and the ratio of HgS to HgO was about 6:1.In addition to the above major components,the Zhu Hong ointment also contained toxic heavy metals such as soluble mercury,lead,arsenic,and cadmium,in which the average content of soluble mercury was as high as 0.804 mg/g.2.Mercury penetrated the skin in inorganic form and did not convert into organic mercury.The damaged skins of different levels were dealt by different ways.The histopathological results indicated that the structure of normal skins were intact,and the skins were deleted partial epidermis by dealing with abrasive paper,and the skins were deleted intact dermis by dealing with depilatory.The penetration rate of mercury on the normal skin was significantly lower than the other two groups,but the penetration rates of the other two groups were basically same.3.The mercury that Zhu Hong ointment absorbed into the organism was in the form of inorganic mercury and did not convert into organic mercury.Mercury accumulated in rat urine,blood,liver,kidney and brain after 4 weeks.The mercury levels in urine,blood,and liver,kidney,and brain of rats in the over-dose groups were significantly different from those in the control group.In the normal dose group,the urine,blood and brain mercury levels were significantly different from the control group.Accumulation of Hg:Kidney>Liver>Brain.Accumulation of mercury in the liver and kidney was significantly dose-dependent.The high dose of Zhu Hong ointment would increase the serum ALT significantly,and the middle dose and high dose of Zhu Hong ointment would increase serum Cr significantly.The long-term use of medium-and high-dose Zhu Hong ointment would destroy the structure of the hepatic lobules,leading to visible necrosis of the nipple lobe.At the same time,it also leaded to tubular lumen shrinkage,glomerular atrophy,Bowman’s capsule enlargement,and other kidney toxicity.The normal dose of Zhu Hong ointment had no obvious changes in the histomorphological of the liver,but it had a slight effect on the kidneys.Conclusion:The toxic components in Zhu Hong ointment include HgS and HgO,soluble lead,cadmium,mercury,and arsenic.The soluble mercury content is high and needs to be controlled.Mercury penetrates the skin in inorganic form and does not convert to organic mercury during percutaneous absorption and in rats.The stratum corneum is the main obstacle which effected the transdermal absorption of mercury in Zhu Hong ointment.Because skin lesions in clinical patients are usually severe,the stratum corneum is often missing.Therefore,the use of Zhu Hong ointment can not consider the impact of skin damage.Inorganic mercury would accumulate in the liver,kidney,and brain,and it is more likely to accumulate in the liver and kidneys.Under the normal dose and treatment cycle,the toxicity of Zhu Hong ointment to the liver is not obvious.However,there was a significant increase in blood mercury and brain mercury levels,and slight changes in the kidney’s tissue morphology.Urine and blood mercury can be used as a sensitive indicator of nephrotoxicity.It is necessary to pay close attention about nephrotoxicity and neurotoxicity in clinical use.Over-dose Zhu Hong ointment can cause severe toxic damage to the kidneys.It will increase serum Cr and urinary mercury content.Therefore,the above indicators can be used as sensitive indicators of renal toxicity.Over-dose group has obvious liver damage.However,only high doses cause significant changes in biochemical indicators.Therefore,more sensitive indicators need to be found to detect liver toxicity.The above studies provide a material basis for the toxicity of Zhu Hong Ointment.It provides a certain reference for the rational and safe use of Zhu Hong Ointment. |
