Q. Regarding receptor regulation (Solved)

1. Receptor down regulation occurs over hours – days

2. Receptor responses to drugs often “desensitise” with time – this desensitisation is usually irreversible

3. The mechanism of agonist induced desensitisation of the nicotinic Ach receptor has been worked out in detail

4. All “internalised” receptors are degraded by lysosomes

5. None of the above are correct