Primary Study On Scavenging Effect Of Early Hemoperfusion To Diquat And Early Damage In Beagles

Background:Diquat is a kind bipyridyl herbicide with broad-spectrum,rapid contact and herbicidal properties.It can let the weeds quickly wither and dry.It has been widely used in countries around the world since its listing in 1958.With the widespread use of diquat in agriculture and forestry,health problems caused by improper preservation,improper use,and even oral herbicides have also emerged.In the past two years,the number of patients with rapid poisoning of diquat in our department has shown an obvious upward trend.At present,the research on diquat is mostly research on agro-ecology,as well as clinical case reports,and there are few studies on the treatment of diquat poisoning.Blood purification is to take the patient's blood out of the body and through a purification device to remove some of the pathogenic substances,purify the blood,and achieve the purpose of treating the disease.Among many purification methods,hemoperfusion(HP)is commonly used.It is widely used in the treatment of various acute drugs or toxic substances.In the past two years,experimental research on blood perfusion has also been hid,but there is no relevant experimental study on the effect of a treatment method on the elimination of diquat in the body.Conducting research in this area will have a greater guiding significance for clinical treatment.Objective:Taking Beagles as the experimental objects,one group was given hemoperfusion after the rapid application of diquat,and the other group did not take any treatment measures.Record the clinical manifestations of the experimental dogs.Collect the peripheral blood at each time point and detection the concentration of poison in the blood.After 24 hours of exposure,the animals were sacrificed and the organ tissues were dissected to measure the concentration of diquat in the organs.The toxicant clearance effect of hemoperfusion was explored by comparing the toxicant concentrations of the two groups of experimental animals,and the distribution of toxicants in various organs was observed.The liver,kidney and lung tissues were taken for pathological section to observe the pathological damage in the early stage of acute diquat poisoning.Method:Twelve adult male healthy were randomly divided into two groups:group A(control group)and group B(hemoperfusion group),with 6 beagles in each group.After a series of preliminary experiments,it was determined that each dog was intravenously injected of 30 mg/kg of diquat with a concentration of 10%.The indwelling needle is placed in the small saphenous vein of the hind limb of the experimental dog to supply medicine,blood and rehydration.Group A and Group B established a vascular access in the left femoral vein.Then group A did not receive any other treatment while performed hemoperfusion for 2 hours at 2 hours of administration to group B.Heparin sodium was used for anticoagulation during blood perfusion,and the extracorporeal circulation rate was 40 ml/min.After hemoperfusion,protamine was neutralized with heparin.The blood of the Beagles was collected at 0.5h,1h,2h,4h,6h,8h,12h,24h after exposure,and the concentration of diquat in the blood at each time point was detected.The 2h and 4h of group B were collected before and after hemoperfusion to avoid the influence of physiological saline and heparin.When collecting blood through an indwelling catheter,first take 5 ml of blood and then collect the specimen.After 24 hours,the dogs were deeply anesthetized and sacrificed.The liver,kidney,lung,heart,small intestine and spleen tissues were taken.After homogenization,the supernatant was taken to detect the concentration of diquat in the tissue.Liver,kidney,and lung were taken for pathological sectioning,including HE and Masson staining.The liquid chromatography-mass method was used to quantitatively determine the concentration of diquat in canine plasma and tissues,and each data was detected and recorded.The data is expressed as mean±standard deviation,and the analysis method uses t-test of the group design data.The statistical software uses spssl7 statistical software.P 0.05 was considered to be statistically significant.Results:(1)There were 3 animals in the experimental group who developed convulsions during the perfusion therapy.The animals were kept warm and the hemoperfusion was not stopped.After the end of the hemoperfusion,there were 2 experimental animals with obvious oozing at the catheter,and the amount of protamine was increased in an appropriate amount,and the osmotic blood was improved after the pressing time.Two experimental animals in the experimental group and the control group developed diarrhea.All experimental animals did not die within the observation period of 24h after administration.(2)Comparing the concentration of peripheral venous blood at each time point of the two groups of experimental animals,there was no statistically significant difference in the concentration of diquat in the two groups before the hemoperfusion.At 4h after the exposure,the end of the hemoperfusion,the concentration of diquat in the experimental group was significantly lower than that in the control group(P<0.05).The concentration of diquat in the two groups recovered to a similar level 6h after exposure(P>0.05).There was no statistical difference in the concentration of diquat in the two groups of experimental animals until 24h(P>0.05).(3)Comparing the concentration of diquat in the heart,liver,spleen,lung,kidney and small intestine tissues of the two groups of experimental animals,the concentration of diquat in the heart,liver,spleen,lung and small intestine was not statistically different(P>0.05).The diquat concentration of kidney of the experimental group was significantly lower than that of the control group.The content of diquat in the kidneys is much higher than that of other organs,and the concentration of diquat in the lungs is the lowest.(4)The liver and kidney function indexes of each experimental animal before administration(blank control)and 2h.?4h.?and 24h after administration were compared:At 2h after administration,compared with the blank control,BUN in the non-treated group was significantly increased(P<0.05);The ALT AST BUN was significantly increased(P<0.05).There was no significant difference between the treatment group and the non-treatment group(P>0.05).At 4h after administration,compared with the blank control,ALP BUN Cr was significantly increased in the non-treated group(P<0.05);ALP BUN Cr was significantly increased in the treatment group(P<0.05);there was no significant difference between the treatment group and the non-treated group(P>0.05).At 24 h after administration,compared with the blank control,the indexes of the non-treated group were significantly increased(P<0.05);the AST ALT AST BUN of the treatment group was significantly increased(P<0.05);the BUN?Cr was significantly higher in the treated group than in the non-treated group(P<0.05).(5)After 24 hours of exposure,the liver,kidney and lung tissues were taken for pathological section.Liver HE staining of control group showed many hepatic cells with mild edema,swelling of the cells,cytoplasmic loosening.Many granulocyte-based white blood cells can be seen in more venous lumens and hepatic sinusoids;hepatic sinus congestion was seen in many tissues.A small amoumt of neutrophils can be seen in some venous lumens,and more neutrophils are seen in the hepatic sinus.A small amount of neutrophil infiltration is seen in the connective tissue around some veins;some connective tissue around the vein is loose,accompanied by a small amount of inflammation.There are sexual cell infiltration and no other obvious abnormalities:in the tissue.Liver Masson stained sections showed no significant fibrosis in the tissue.Hepatic sinus congestion and mild inflammatory cell infiltration were observed in the HE staining sections of the experimental group.No obvious extensive watery cell degeneration was observed.The liver Masson stained sections showed no obvious fibrosis in the tissues.Renal HE staining of control group showed renal tubular epithelial cell swelling,cytoplasmic loosening,renal tubular epithelial cells detached from the basement membrane;a small amount of renal tubular epithelial cells watery degeneration;no obvious abnormalities were observed in the tissue.Kidney Masson stained sections showed no significant fibrosis in the tissue.In the experimental group,HE staining of the kidney showed swelling of renal tubular epithelial cells and a small amount of renal tubular epithelial cells with water-like degeneration.Masson-stained sections of the kidney showed no obvious fibrosis in the tissue.Lung HE staining of control group showed extensive thickening of the alveolar wall in the tissue,accompanied by a large amount of inflammatory cell infiltration;more white blood cells were seen in the lumen of the vessel;alveolar wall rupture occurred in many tissues,small alveoli merged into a large cyst;local alveolar exfoliated epithelioid cells were seen in the lumen;no other abnormalities were observed in the tissue.Lung Masson-stained sections showed more blue staining of collagen on the thickened alveolar wall.The lung HE staining of the experimental group showed extensive inflammatory cell infiltration,and no extensive alveolar wall rupture was observed.The lung Masson-stained sections showed a little blue staining of collagen on the thickened alveolar wall.Conclusion:The method of intravenous poisoning is simple to operate and the dose can be accurately controlled.Hemoperfusion can significantly reduce the concentration of toxic substances in the blood,and then the blood concentration in the short-term rebound significantly to a similar concentration to the non-treated group.Until 24h,there is no significant difference in blood concentration between the two groups of animals.The concentration of organs in the body exposed to diquat for 24h showed that the concentration of diquat in the kidneys of the experimental animals which receiving the hemoperfusion was significantly lower than that in the group without hemoperfusion.It is necessary to have hemoperfusion in the early stage of acute poisoning of diquat.Two hours after the administration,the liver and kidney function indexes of the two groups of animals showed abnormalities.The abnormality of each index was aggravated.There was no significant difference between the treatment group and the non-treatment group.At 24 hours after administration,the indexes of the two groups of animals were all different.Significant abnormalities,BUN Cr was significantly lower in the treatment group than in the non-treatment group The pathology showed that collagen hyperplasia occurred in the lungs,and the liver and kidney showed different degrees of cell water-like changes and inflammatory reactions.