Adrenergic nerve fibre

An adrenergic nerve fibre is a neuron for which the neurotransmitter is either adrenaline (epinephrine), noradrenaline or dopamine. These neurotransmitters are released at a location known as the synapse, which is a junction point between the axon of one nerve cell and the dendrite of another. The neurotransmitters are first released from the axon and then bind to the receptor site on the dendrite. Adrenergic nerve terminals are found in the secondary neurons of the sympathetic nervous system, one of two deviations of the autonomic nervous system which is responsible for your fight-or-flight response. This systems increases heart rate, slows digestion, dilates pupils, and also controls the secretion of apocrine sweat glands in the dermal layer of skin, in addition to other responses.