• Journal of Yeungnam Medical Science
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• 제16권2호
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• pp.326-332
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• 1999

이 연구에서는 유기인제 농약으로 인한 acetylcholinesterase와 pseudolcholinesterase의 활성도 변화와 알콜과 유기인제 농약의 상호 작용시 효소 활성도 변화를 비교하고, 임상적으로 쓰이고 있는 가역성 항콜린에스터라제 약물과도 비교하여 여러 항콜린에스터라제 약물의 효능과 알콜 섭취가 콜린에스터라제 활성도에 미치는 영향을 파악하는 것에 이 실험의 목적을 두었다. 남자 대학생 15명을 무작위 추출하여 상박부 정맥에서 채혈하여 혈액중 적혈구내에 존재하는 acetylcholinesterase와 혈장에 존재하는 acetylcholinesterase를 분리하였고 cholinesterase가 acetylcholine을 acetic acid와 choline으로 가수분해한다는 점을 이용하여 각 효소에 acetylcholine을 기질로서 주입한 후 1시간 후 생성된 acetic acid에 의해 변화된 pH를 pH meter로 측정하여 간접적으로 활성도를 알아내는 electrometric method를 이용하여 활성도 변화를 측정하였다. 위 실험 조건에서 가역성 항콜린에스터라제 약물이 유기인제 농약보다 콜린에스터라제 활성도를 감소시켰고, 유기인제로 인한 acetylcholinesterase와 pseudocholinesterase의 활성도 변화는 에탄올 처치시 더욱 현저하게 감소되는 것으로 나타났으며, 콜린에스터라제 활성제인 oxime은 acetylcholinesterase에 대해서는 효소 활성도를 높이지만 pseudocholinesterase의 효소 활성도에는 영향을 미치지 않는 것으로 나타났다.

• BMB Reports
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• 제36권2호
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• pp.149-153
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• 2003

The dibucaine number (DN) was determined for serum cholinesterase (EC 3.1.1.8, SChE) in plasma samples. The ones with a DN of 79-82 were used, because they had the "usual" SChE variant. The enzyme was assayed colorimetrically by the reaction of 5,5'-dithiobis-[2-nitrobenzoic acid] (DTNB) with the free sulfhydryl groups of thiocholine that were produced by the enzyme reaction with butrylthiocholine (BuTch) or acetylthiocholine (AcTch) substrates, and measured at 412 nm. Dibucaine, a quaternary ammonium compound, inhibited SChE to a minimum within 2 min in a reversible manner. The inhibition was very potent. It had an $IC_{50}$ of $5.3\;{\mu}M$ with BuTch or $3.8\;{\mu}M$ with AcTch. The inhibition was competitive with respect to BuTch with a $K_i$ of $1.3\;{\mu}M$ and a linear-mixed type (competitive/noncompetitive) with respect to AcTch with inhibition constants, $K_i$ and $K_I$ of 0.66 and $2.5\;{\mu}M$, respectively. Dibucaine possesses a butoxy side chain that is similar to the butryl group of BuTch and longer by an ethylene group from AcTch. This may account for the difference in inhibition behavior. It may also suggest the existence of an additional binding site, other than the anionic binding site, and of a hydrophobic nature.

• Applied Microscopy
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• 제14권2호
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• pp.66-80
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• 1984

The organic phosphorus compounds have been widely used as an insecticide, since toxicity of these compounds is especially drastic to the insects than to men and other mammals. The organic phosphates are rapidly hydrolized and hence have little cumulative and ecologic effects. However, due to their acute toxic effects organophosphate have recorded rather high fatalities in men and domestic animals. The organic phosphorus compounds are powerful inhibitors to the carboxylic esterase enzymes such as acetylcholinesterase and pseudocholinesterase. As a result of firm binding characteristics of phosphate radicals to the active sites of enzyme, the activities of these enzymes are inhibited by the organophosphates. The organophosphates such as diazinon is easily observed from skin, gastrointestinal tract, conjunctivas and respiratory tract, and it is converted to more toxic form during metabolism in the liver The present study was carried out in order to investigate the hepatotoxicity of diazinon by observing the changes in the ultrastructure of cytoplasmic organelles of hepatic cells in albino mice. The animals were killed at 6, 12 and 24 hours after administration of 25mg/kg diazinon. The piece of hepatic tissue obtained from each animal was ultrathinly sectioned. The specimens stained by uranyl acetate and lead citrate double contrast methods were observed with JEM model 100B electron microscope. The results obtained were as follows: 1) A prominent dilatation and sacculation of the cisternae of rough endoplasmic reticulum associated with detachment of membrane bound-ribosomes, and disaggregation of the free ribosomes were recognized. 2) The hypertrophy of the smooth endoplasmic reticulum associated with depletion of the glycogen particles was observed. 3) The atrophy of cisternae of Golgi complex was observed. 4) A large number of secondary lysosomes (autophagic vacuoles and residual bodies) were formed. Consequently it is suggested that diazinon would induce disorganization of the cytoplasmic organelles of hepatocytes in albino mice.

• 대한임상독성학회지
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• 제8권1호
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• pp.16-23
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• 2010

Purpose: Organophosphate insecticide poisoning is common in Korea, but there is no definitive guideline for determining the severity of the poisoning and the predictive factors. Therefore, we evaluated the organophosphate poisoned patients and we divided them into two groups, the survivors and the dead, and the results might be useful for treating organophosphate poisoning patients. Methods: We performed a retrospective analysis of 68 organophosphate poisoned patients who visited the Chosun University Hospital Emergency Medical Center during a 24-month period from January, 2007 to December, 2008. We made a work sheet of the patients' characteristics and the collected data was analyzed and we compared this data between the survivor group and the dead patient group. Results: There were significant differences between the survivor group and the dead patient group for the mean age, the alcohol intake state and the typically expressed signs. The dead patients had lower blood pressure, tachycardia and a lower Glasgo Coma Score (GCS) score than the survivor group. On the arterial blood gas analysis, the dead patients had more severe acidemia and they had lower saturations. Increased serum amylase levels were found in the dead patients. The survivors'initial and follow up serum pseudocholinesterase activity (after 6~8 days) was significantly higher than that of the dead group. The total amount of atropine injected to patient was less in the survivors than that in the dead patients. Conclusion: Old age and expressing the typical intoxication signs, a lower GCS score and blood pressure, showing acidosis on the gas analysis and low serum cholinesterase activity may be useful as poor prognostic indicators for patients with organophosphate poisoning. We suggest that physicians must pay careful attention to the signs and prognostic factors of organophosphate insecticide poisoned patients.