How does the nervous system and endocrine work together when adrenaline is released?I don't quite understand that!..I know endocrine system...

In a fight or flight response, there is a coordination of
both the nervous and endocrine systems. The nervous system detects stimuli, either
inside or out, for example, danger like an oncoming car about to run someone over,  and
that in turn sends an impulse to the endocrine system where a response is carried out.
The response in this case is the release of adrenaline into the bloodstream, by the
endocrine glands called adrenal glands. Once in the bloodstream, this hormone can cause
the heart rate to increase, the muscles to become ready to either react to an emergency
situation by fighting or by flight.