抗寄生虫药Antiparasitedrugs的学习教案.pptxVIP

抗寄生虫药Antiparasitedrugs的学习教案;Human parasite; Antimalarial drugs;;第5页/共55页;Four species of plasmodium can produce the disease in its various forms: Plasmodium falciparum （恶性疟原虫） Plasmodium vivax （间日疟原虫） Plasmodium ovale （卵形疟原虫） Plasmodium malaria （三日疟原虫） ;;No one available agent can reliably effect a radical cure, ie, eliminate both exo-erythrocytic and erythrocytic stages. Few available agents are causal prophylactic drugs, ie, capable of preventing erythrocytic infection.;;Antimalarial drugs – Chloroquine （氯喹）;Pharmacological effects 1. Antimalarial effects Rapid schizonticidal activity （裂殖体杀灭剂） against all infections of malaria species . Also gametocytocidal（杀配子体）against P. vivax, P. malariae and P. ovale . It is not active against exo-erythrocytic form, and should therefore be used with primaquine（伯氨喹）to effect radical cure of P. vivax. ;Pharmacological effects 2. Immune inhibition Treatment of rheumatoid arthritis, lupus erythematosus 3. Extraintestinal amebiasis Amoeba trophozoite amebic liver abscess ;Mechanism of actions Accumulation in erythrocyte→pH↑ → malarial pigment synthesis↓ → heme↑ Heme-quinoline compound → heme accumulate in plasmodium ↑ Insert in the double stranded DNA helix → DNA replication and RNA transcription ↓;Adverse effects Rare at the usual antimalarial dosages Pruritus (瘙痒症) common among dark-skinned people. Transient headaches, nausea, vomiting, gastrointestinal symptoms and “blurred vision”. Others: aplastic blood and neurological disorders, such as polyneuritis (多发性神经炎), seizures and neuromyopathy. ;Quinine （奎宁） Mefloquine （甲氟喹） Pyronaridine (咯萘啶) Artemisinin (青蒿素) Artemether and artesunate (蒿甲醚和青蒿琥酯) ;;Pharmacological effects Highly active against the gametocytes (配子体) of all malaria species →dissemination ↓ Active against hypnozoites (迟发型子孢子) of the relapsing malarial parasites The only drug currently used for the treatment of relapsing malaria ;Mechanism of actions Inhibition of coenzyme Q Inhibition of r