Addiction

Question 1

What is the working of nicotine, and why is it so addictive?

Answer 1

Nicotine is the most addictive drug.

Targets heteromeric α4β2 receptors.
-during the first few puffs, nicotine directly stimulates DA neurons by acting upon α4β2 nACh receptors.
-after one cigarette, most of these receptors are desensitised, which results in reduced tonic inhibition of DA neurons. In other words, DA neurons are more easily activated by excitatory input -> prone to addiction.

Question 2

What are drugs for smoking cessation?

Answer 2

• bupropion (NDRI)
• yellow flower (but highly toxic in high doses)

Question 3

What are the toxic components in alcohol?

Answer 3

Ethanol is concerted to the toxic component Acetaldehyde by ADH, and broken down into acetic acid by ALDH.

Question 4

How does alcohol work in the body?

Answer 4

Alcohol serves as a PAM at extra-synaptic GABAa receptors.