Neurotoxicology Flashcards
Role of Glial cells
Protects CNS cells from disease engulfing invading microbes
Why is the Nervous system a sensitive target for pollutants?
Neuronal damage is irreversible. Neurones cannot normally regenerate
High metabolic rate, little capacity for anaerobic metabolism
Nerve cells have a large surface area hence more susceptible to damage
Being electrically excitable, neurons tend to lose cell membrane integrity more readily
Physical protection for the Nervous System
Neurons lie within the body surrounded by myelin sheath
Immunological protection for Nervous System
Microglial cells phagocytose microorganisms and other foreign materials
What is the Blood Brain Barrier?
tightly packed endothelial cells and astrocytes that line the capillaries of the brain
Is the Blood Brain Barrier (BBB) an idea or organ?
BBB is not a distinct organ but a functional concept
What are Neurotoxicants?
agents causing adverse functional or structural changes in the nervous system
What % of all commerically used chemicals may have neurotoxic potential?
30%
Environmental Neurotoxicants
Pesticides/ Biocides
Metals
Pharmaceuticals
Toxic Algal Blooms
Signs of Neurotoxicity (5)
Motor effects- tremor, coordination, movement
Mood- excitability, irritation
Cognitive effects- altered behaviour
Sensory- vision, hearing
General- muscle weakness, fatigue, narcosis (a state of drowsiness or unconsciousness)
Mechanisms of Neurotoxicity
Electrical conduction
Cell body
Inhibition of Synaptic transmission
What does an increase in GABA do?
Decrease electron excitability/ calm you down
What is Fluoxetine and what does it do (biologically)
Antidepressant
Increases seretonin levels in synapses by inhibiting serotonin transporters (prolongs mood lightening effect)
What enhances the natural effect of GABA and where is it found (not meant to be there)?
Benzodiazepines enhance the natural effect of GABA to reduce neural activity even further
Found in wastewater effluent
Are Benzodiazepines photo-resistant?
YES!
