恶性疟原虫乳酸脱氢酶活性测定及在药物疗效监测方面的初步观察

目的 探讨疟原虫乳酸脱氢酶（Plasmodium lactate dehydrogenase,pLDH)活性与原虫密度，培养时间的关系。以及在监测药物疗效等方面的作用。方法 利用酶比色法对不同原虫密度不同培养时间以及药物治疗前后患者的血样进行pLDH活性检测。结果 pLDH的活性随恶性疟原虫感染率的提高，培养时间的增加而明显地升高，最大活性是在虫体培养36-48h之间，虫体主要处在裂殖体期和滋养体期；混合感染（恶性疟原虫和间日疟原虫）患者经药物治疗后血液中pLDH活性明显降低，治疗5d后已检测不到pLDH的活性。结论 pLDH活性检测对于疟原虫克隆株鉴定，药物的疗效监测等方面具有一定的应用价值。

Plasmodium lactate dehydrogenase activity assay and its preliminary application in therapeutic efficacy monitoring of drugs.]

OBJECTIVE: To evaluate the activity of Plasmodium lactate dehydrogenase (pLDH) in relation to the degree of parasitemia and laboratory culture time of the parasite, and explore the feasibility of using the activity assessment in monitoring the effect of drug therapies. METHOD: Using enzymatic colorimetric method, pLDH activities were assayed in the blood samples of different degrees of parasitemia and of varied in vitro culture time. Blood samples from a patient with P.falciparum and P.vivax infection were also collected before and after chemotherapy for pLDH activity assay. RESULTS: pLDH activity increased as parasitemia escalated and the culture time prolonged. The strongest activity was observed between 36 and 48 h of incubation when the trophozoites and schizonts were predominant. pLDH activities were reduced in the blood sample of the patient collected after chemotherapy, completely undetectable after 5 d. CONCLUSION: pLDH activity assay would potentially be of value in detecting specific Plasmodium clones and monitoring efficacy of drug therapy.