Detailed Instructions: Given a scientific passage and an answer, generate a question for the given answer.
Q: Passage: Adrenaline, or epinephrine, is a hormone and a neurotransmitter. It increases heart rate, constricts blood vessels, dilates air passages, and participates in the fight-or-flight response of the sympathetic nervous system. Adrenaline is produced in the adrenal medulla of the adrenal gland. So how does it effect processes all over the body?. Answer: adrenaline
A:
What neurotransmitter is associated with the fight-or-flight response?