Experimental Studies On The Toxicity Of Trypsin And Its Preparation

Trypsin is the earlist discovered digestion enzyme which was found in pancreatic juice.Trypsin is a kind of protease in vertebrate digestion system as a digestion enzyme.It is synthesized as a prosoma-trypsinogen in the pancreas,secrete into small intestine through pancreas tubular as a component of pancreatic juice,and then become an active trypsin after activated by enterokinase.Trypsin can selectively cleaving polypeptide at the carboxyy side of arginine and lysine residues.Trypsin also can active the prosoma of some enzymes such as procarboxypeptidase,chymotrypsinogen.Trypsin is the most specificity protease.As a protease,trypsin can digest denatured protein,but doesn't work on active protein.Therefore,trypsin can make pus or blood clot easy to draw upon and remove by resolving and attenuating,to accelerate the necrosis wound surface decontamination,promote regeneration of granulation tissue.Trypsin is used to cure empyema,hemothorax,local-edema caused by fistulae,and abscess,and also used to cure thanatophidia bite in human clinics;Biotechnologically,trypsin usually used in cell culture.Up to now,however,trypsin including toxicology is rarely reported in veterinary clinics.According to the toxicology test method of veterinary drugs register document assembly by Veterinary Drugs Judgment Center,Chinese Ministry of Agriculture,the toxicities studies of trypsin such as the mice acute toxicity test,rat subchronic toxicity test,mice bone marrow cells micronucleus test,and the rabbit skin stimulatory tests and the skin sensitization test of the compound proteinase,rabbit mucous membrane stimulatory test of the compound proteinase were studied in this paper.After oral administration of trypsin at the dosage of 40 mg/kg,200 mg/kg,1000 mg/kg,5000 mg/kg,8000 mg/kg respectively,the results showed that the acute toxicity test of trypsin on mice is LD50>5000 mg/kg.According to the toxicity grade standard of chemistry materials,trypsin is belongs to the practical innoxious substance.The subchronic toxicity test based on 30-days oral administration at the dosage of high dose(800 mg/kg),middle dose(400 mg/kg),low dose(200mg/kg)of trypsin respectively,there is no obvious poisoning reaction in each experimental group.Although there are significant changes of some parameters,all index of the blood routine parameters and blood chemical parameters are in the range of normal parameter limits.Compare to the control group,there is no significant organ coefficient change,and no obvious abnormal histopathological lesion is found in the tested organs.The rabbit skin stimulation test and the rabbit skin sensitization test,after the compound proteinase smeared on the back skin of rabbit,showed that the compound proteinase do not cause skin stimulatory reaction.And there is no stimulatory reaction on vagina mucous membrane after injection of the compound proteinase agent into the rabbit vagina.After administration of trypsin at the dose of LD50(5000 mg/kg,)?1/2 LD50(2500 mg/kg)?1/4 LD50(1250 mg/kg),the mice bone marrow micronucleus test showed the negative result,indicating that trypsin has no mutagenic action on mice somatic cell.