— Neuropeptides, the second type of ligand, make up the majority of
these messengers. Most are manufactured in a structure of the brain called
the hypothalamus (recent studies show that our immune system also makes
them). These chemicals are passed through the pituitary gland, which then
releases a chemical message to the body with specific instructions.
— As neuropeptides make their way through the bloodstream, they attach
to the cells of various tissues (primarily glands) and then turn on the third
type of ligand, hormones, which further influence us to feel certain ways.
Neuropeptides and hormones are the chemicals responsible for our feelings.
For our purposes, think of neurotransmitters as chemical messengers
primarily from the brain and mind, neuropeptides as chemical signalers that
serve as a bridge between the brain and the body to make us feel the way
we think, and hormones as the chemicals related to feelings primarily in the
body.