Studies Of Renqingmangjuewan On The Safety Assessment And The Comitant Toxicokinetic

Objectives:To investigate the toxicokinetics of strychnine alkaloid and tissues distribution of lead, copper,mercury and strychnine alkaloid on the basis of safety evaluation of Renqingmangjuewan such an its acute toxicity test and chronic toxicity study, to clarify the metabolic outcome and poisonous ingredient for the accumulation of harm, and to provide the experiment data for the clinical of RenqingmangjuewanMethods:(1) Acute toxicity test. The toxic reaction and the death condition were observed in mice after orally administered once the maximum administration dosage of Renqingmangjuewan. (2) Chronic toxicity test. It includes the rodent and non-rodent tests. Sprague-Dawley Rats were successively received Renqingmangjue in doses of 0.5,1.0 and 2.0 g (crude drugs)·kg-1 BW for 3 morth, which were equal to about 20,40 and 80 times clinical dosage.Beagles were treated with 0.375,0.75 and 1.5 g (crude drugs)·kg-1 BW of Renqingmangjuewan for a successive course of 3 months through oral administration,which were equal to about 15,30 and 60 times clinical dosage.We observed the toxic reaction and severity in rats and Beagles in continuous oral administration of 3 months, and also observed the development and recovery after the withdrawal of Renqingmangjuewan. (3) Studies on tissues distribution of lead, copper and mercury after oral administed Renqingmangjuewan. The concentrations of lead, copper and mercury in brain, heart, liver, spleen, lung, kidney, stomach-duodenal,colon and blood of rats and beagle which were tested in chronic toxicity test were determined by atomic absorption spectrometry. (4) Toxicokinetics and distribution of strychnine alkaloid in rats and beagles.The LC-MS/MS method was established for the determinations of strychnine and brucine in rats and Beagles which were tested in chronic toxicity test, to explore the toxicokinetics of strychnine and brucine after single or repeated oral doses, and tissue distribution of strychnine and brucine.Results:(1) The maximum administration dosage by oral adminstration was 24.48g (crude drugs)·kg-1BW,which is 979 times more than the daily human adult the maximum dose in clinic. No death was observed and no significant changes in body weight were found. So it indicated that Renqingmangjuewan was no acute toxicity by oral administration in mice and it belong to no obvious toxic subordinates varieties in clinical recommend doses. (2) No significant differences of the physical conditions, hematology, hematic biochemistry, and histopathology were found in the rats and beagles.observed the pathological and histological changes.It was indicated that Renqingmangjuewan had low toxicity after long-term oral.It is thought that the safe dosage for oral administration were 2.0 g (crude drugs)·kg-1 BW in SD rats and 1.5 g (crude drugs)·kg-1 BW in Beagles. (3) The copper and mercury in rats or Beagles which were tested in chronic toxicity test were mainly distributed in kidney. It was shown that the copper and mercury may be cumulative in kidney. But withdrawal after recovery, their contents in the kidney decreased.(4) After Renqingmangjuewan were orally administered repeated to Sprague Dawley rats, the plasma concentrations of strychnine and brucine in the low dosage were the lowest.Then the AUCss, Cmax of strychnine in the middle and high doses were 172.43,296.12μg·h-L-1; 41.57,48.47μg·L-1, respectively,when the AUCss, Cmax of brucine in the middle and high doses were 11.96,40.48μg·h·L-1; 5.64,9.98μg·L-1, respectively. (5) The AUCss of strychnine for single oral administration in the low, middle and high groups of Beagles were 9.01,16.39 and 30.65μg·h·L-1, respectively,which were positively related to drug doses with correlation coefficient by 0.9999. The Cmax of strychnine for single oral administration in the low, middle and high groups of Beagle were 5.26, 7.30 and 6.59μg·L-1, respectively. The AUCss and cumulative coefficient of strychnine for repeat oral administration in the low, middle and high groups of Beagles were 80.81,58.17,170.92μg·h·L-1; 8.97,3.55,5.58, respectively.Meanwhile, whether single or repeat oral administration,the plasma concentration of brucine in each group was low. (6) Strychnine and brucine were distributed widely in some tissues of animals which were experimented in the chronic toxicity test. Their contents were the highest in stomach-the duodenum of rats than other tissues.Conclusion:Both acute toxicity and long-team toxicity after oral administration of Renqingmangjuewan were low.The metabolism process of strychnine in Beagle belong to linear pharmacokinetics, meanwhile, the accumulation of strychnine and brucine were low, so it suggested the recommended dosage of Renqingmangjuewan in clinical relatively was safe product. But after long-term and more doses, mercury was in a certain cumulated in the kidney.