Antiparasitic Agents

Question 1

Name the two main types of parasites?

Answer 1

Protozoa (uni-cellular) + Metazoa (worms)

Question 2

What is a nematode?

Answer 2

roundworm

Question 3

What is a cestode?

Answer 3

tapeworm

Question 4

Malaria is what type of parasite? the most common and deadly form of malaria parasite?

Answer 4

blood protozoa

Plasmodium falciparum

Question 5

Summarise the mechanism of action of Chloroquine

Answer 5

1. Malaria infects RBCs: the plasma membrane invaginates and wraps around malaria (parasitophorous vacuole)
2. Within the vacuole, the parasite uses the transporters to important things such as haemoglobin (protein meal)
3. However, haem can be toxic to the malaria and the enzyme haem polymerase makes it ‘clump’, so it neutralises the toxic effect

Chloroquine - inhibits haem polymerase.
Effect = haem does not ‘clump’, and is toxic to and kills parasite