Chapter 24, Problem 19RQ

To determine

The location of opioid sites.

Answer to Problem 19RQ

Opioid receptor sites are located on the neurons in the central nervous system, which includes the brain and spinal cord.

Explanation of Solution

Initially receptor sites raised the question of why they exist. Later it was assumed that, it mimics the action of the naturally occurring brain chemical. The more potent opioid analgesic – morphine, codeine and heroin- moderate the brain perception of pain by binding to receptor sites on neurons in the central nervous system, which includes the brain and spinal column. Endorphins, a group of large biomolecules that have strong opioid activity were subsequently isolated from brain.

Conclusion:

Therefore, Opioid receptor sites are located on the neurons in the central nervous system, which includes the brain and spinal cord.