Hormones:

Hormones are produced in endocrine glands and are secreted into and transmitted through the bloodstream. They act differently in the body from neurohormones, as follows:

• Hormones must be made on demand. Neurohormones can be stored in vesicles (cellular envelopes that transport materials from one place to another) and released when needed.
• Hormones only act on effector tissues (bodily tissues, structures, or organs—like glands or muscles—that respond to stimulation). Neurohormones only act on endocrine tissue to initiate the release of a different hormone.
• Hormones are circulated by bloodstream. Neurohormones are circulated by nerves.
• Hormones are released from specialized endocrine glands or cells. Neurohormones are released from modified nerve cells.