The pituitary gland is the sort of like, the nucleus of the endocrine system (essentially the system of cell to cell communication whereby an endocrine cell in a gland can send a signal to a target cell via secretions of hormones into the blood stream). It is responsible for the secretion of Human Growth Hormone, Antidiuretic Hormone (for osmoregulation), Hormones pertaining to secondary sexual characteristics, Thyroid stimulating hormone, Prolactin (to do with breast milk production during gestation) and Adrenocorticotrophic hormone (to do with stimulating cortisol, which is to do with stress).
Pretty long, but I hope this helps :)
