Chemical messengers that are released by axons and stimulate dendrites on another neuron are called

Neurotransmitters

Explanation:

Neurotransmitters are chemical compounds produced by neurons and communicated by synapses, which are responsible for transmitting the necessary information to various parts of the body.

Thus, these chemical mediators are generally found in presynaptic vesicles and may be amines (dopamine, serotonin, melatonin, epinephrine and norepinephrine), amino acids (glutamate, aspartate, glycine, serine and gamma-aminobutyric acid “GABA”) or peptides ( calcitonin, glucagon, vasopressin, oxytocin and beta-endorphin).

well, i believe that the answer is 2. : 3