Ovaries secrete estrogens and progesterone, and the testes secrete androgens, such as testosterone.Īlthough it is against Federal laws and many professional athletic associations (The National Football League, for example) have banned their use, anabolic steroid drugs continue to be used by amateur and professional athletes. The female gonads are the ovaries the male gonads are the testes.

The gonads secrete sexual hormones, which are important in reproduction, and mediate both sexual motivation and behavior. People who suffer from diabetes do not produce enough insulin therefore, they must take medications that stimulate or replace insulin production, and they must closely control the amount of sugars and carbohydrates they consume. These pancreatic hormones are essential for maintaining stable levels of blood sugar throughout the day by lowering blood glucose levels (insulin) or raising them (glucagon). The pancreas is an internal organ that secretes hormones that regulate blood sugar levels: insulin and glucagon. The adrenal glands sit atop our kidneys and secrete hormones involved in the stress response, such as epinephrine (adrenaline) and norepinephrine (noradrenaline). Fortunately, thyroid disorders are often treatable with medications that help reestablish a balance in the hormones secreted by the thyroid. In hypothyroidism, reduced hormone levels cause sufferers to experience tiredness, and they often complain of feeling cold. One cause of hyperthyroidism is Graves' disease, an autoimmune disease in which one’s own body attacks itself. In hyperthyroidism, the thyroid secretes too much of the hormone thyroxine, causing agitation, bulging eyes, and weight loss. Located in the neck, the thyroid gland releases hormones that regulate growth, metabolism, and appetite.

In addition to messenger hormones, the pituitary also secretes growth hormone, endorphins for pain relief, and a number of key hormones that regulate fluid levels in the body. The pituitary is often referred to as the “master gland” because its messenger hormones control all the other glands in the endocrine system, although it mostly carries out instructions from the hypothalamus. The pituitary gland descends from the hypothalamus at the base of the brain, and acts in close association with it.

This section explores some of the major glands that make up the endocrine system and the hormones secreted by these glands ( Table 3.2). Imbalances in hormones are related to a number of disorders. Hormones are involved in regulating all sorts of bodily functions, and they are ultimately controlled through interactions between the hypothalamus (in the central nervous system) and the pituitary gland (in the endocrine system). Figure 3.30 The major glands of the endocrine system are shown.

Hormones secreted by adrenal gland