Deck 20: The Nervous System and Exposure to Lipophilic Toxicants or Transported Neurotoxic Agents

Question 1

What is the blood-brain barrier and how is it breached by agents such as 3-chloropropanediol?

Answer 1

Specialized epithelial cells excluding molecules>400 Da. Astrocytes support the BBB and damage to them with agents such as 3-chloropropanediol will breach the BBB.

Question 2

How is the choroid plexus of interest in determining damage to the BBB?

Answer 2

This is the site of CSF which bathes the brain. Metal damage here is separated in direct damage (Hg & Cd), transthyretin production and secretion pathway (Pb), and sequestered protective metal portion (Fe, Ag, Au).

Question 3

How might calcium disruption cause brain toxicity?

Answer 3

Via NMDA receptor (e.g. glutamate) or non-NMDA receptor (domoic acid).

Question 4

How can protein disruption lead to CNS problems?

Question 5

What are examples of chemicals that alter gene expression to cause at least part of their neurotoxicity?