The pituitary gland regulates various body functions and plays an important role in balancing hormone levels in the body. It is a protrusion at the base of the brain and about the size of a pea or cherry. The gland lies well protected in a small bony cavity of the skull, level with the eyes, and roughly in the middle of the head. Show The pituitary gland: Location and individual parts Together with the hypothalamus – which belongs to a part of the brain known as the diencephalon – the pituitary gland controls the involuntary (vegetative) nervous system. This part of the nervous system manages the balance of energy, heat and water in the body, which includes things like body temperature, heartbeat, urination, sleep, hunger and thirst. The pituitary gland also produces a number of hormones that either regulate most of the other hormone glands in the body or have a direct effect on specific organs. The pituitary gland is made up of four parts, each with their own functions:
Anterior lobeThe anterior lobe makes up about three quarters of the overall mass of the pituitary gland. It produces two kinds of hormones:
The group of hormones that control glands includes:
The group of hormones that have a direct effect includes:
The hormones are released into the bloodstream by the pituitary gland and then travel through the blood vessels until they reach the various organs they have an effect on. TSH, for example, stimulates the thyroid gland to increase or reduce the production of thyroid hormones, depending on how much is needed. Prolactin stimulates the growth of girls’ mammary glands in puberty, suppresses ovulation in pregnant women, and triggers the production of breast milk after giving birth. The production of hormones in the anterior lobe itself is regulated in two ways:
Posterior lobeThe posterior lobe of the pituitary gland mainly consists of entangled nerve fibers coming from the hypothalamus. Two different hormones are stored in the posterior lobe. They are released if needed:
The posterior lobe of the pituitary gland is directly connected to the hypothalamus through the pituitary stalk. Hormone-producing tissue is found between the anterior and posterior pituitary, too. Melanocyte-stimulating hormones (MSH) are produced in this intermediate part of the pituitary gland. They stimulate the production of things like melanin in the skin. Melanin is a pigment that protects against harmful ultraviolet sun rays. MSH also regulates our appetite and influences our sex drive. Sources
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