Which of the following neurotransmitters function, both as neurotransmitters and hormones, decreasing our perception of pain?

Explanation

Option D is correct.Epinephrine (also called adrenaline) can act as both a neurotransmitter and a hormone. As a neurotransmitter, epinephrine is released from neurons in the sympathetic nervous system (SNS). The SNS is a part of the autonomic nervous system (ANS), which is responsible for involuntary bodily functions. When the SNS is activated, it releases epinephrine, which causes a number of physiological changes, including:Increased heart rate and blood pressure: This allows the body to deliver more oxygen and nutrients to the muscles.Increased respiratory rate: This allows the body to take in more oxygen and release more carbon dioxide.Dilated pupils: This allows the body to take in more light.Increased sweating: This helps to cool the body down.Goosebumps: This helps to trap heat in the body. Endorphins are neurotransmitters that function both as neurotransmitters and hormones. They are produced by the pituitary gland and the hypothalamus in the brain, and they are released into the bloodstream and the central nervous system. Endorphins bind to receptors on the cells in the brain and spinal cord that are responsible for pain perception. This binding blocks the pain signals from reaching the brain, which results in a decrease in pain sensation.Serotonin, a neurotransmitter and hormone, plays an important role in reducing our perception of pain. Serotonin is a neurotransmitter that is produced by neurons in the brain and spinal cord. It is released into the synaptic cleft, where it binds to receptors on other neurons. This binding triggers a cascade of events that ultimately leads to a change in the activity of the postsynaptic neuron. Serotonin also acts as a hormone. It is released by the brainstem and travels through the bloodstream to other parts of the body. Serotonin receptors are found on many different types of cells, including cells in the gut, the skin, and the immune system.