NUR 209 Lecture Notes - Lecture 32: Pancreatic Islets, Catecholamine, Thyroid Hormones
Document Summary
The endocrine system involves the release of chemical transmitter substances known as hormones. These substances regulate and integrate body functions by acting on local or distant target sites. The endocrine system has a unique relationship with the immune and the nervous systems. The endocrine system is composed of the pituitary gland, thyroid gland, parathyroid glands, adrenal glands, pancreatic islets, ovaries, and testes. Hormones help regulate organ function in concert with the nervous system. The rapid action by the nervous system is balanced by slower hormonal action. This dual regulatory system permits precise control of organ functions in response to changes within and outside the body. Exocrine glands secrete substances that reach their target tissue directly or by traveling through a duct; they include sebaceous, salivary, mammary, and sweat glands. Endocrine glands secrete hormones directly into the blood stream;neuronal stimulation, chemical substances, or hormones can control secretion of endocrine glands.
