11 Hypothal-pit-gland axis

11 Hypothal-pit-gland axis - Glands controlling glands...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Glands controlling glands The control of other hormones is more complex than the simple loop controlling the secre5on (NOT EXCRETION!) of insulin. Many hormones are controlled by a combina5on of neuronal and hormonal signaling. The anterior pituitary consists of several different types of gland cells. • Each cell type releases one or two par5cular hormones. • The anterior pituitary cells release their hormones under the control of neurohormones; the neurohormones are secreted by neurons in one part of the hypothalamus. • All anterior pituitary hormones are pep5des/proteins. (By what mechanism do they affect their target cells?) • Some anterior pituitary hormones control secre5on by the cells in other glands elsewhere in the body. • Some anterior pituitary hormones affect most cells in the body; others have very specific targets. The hypothalamic neurons release their hormones (called releasing factors) into specific capillaries. From there, the blood carries the releasing factors into the anterior pituitary. Regula5on of the thyroid gland provides a good example of the rela5onship between hypothalamic neurons, cells in the anterior pituitary, and another gland. No5ce that this paRern is also a nega5ve feedback loop. Cold s5mulates release of a releasing factor by hypothalamic neurons. The net affect of this endocrine pathway is an increased basal metabolic rate in most cells of the body. The chemical reac5ons of metabolism produce heat, so increasing the release of thyroid hormone generates more heat, and that increases the temperature of the body. ...
View Full Document

This note was uploaded on 02/18/2012 for the course BILD 2 taught by Professor Schroeder during the Spring '08 term at UCSD.

Ask a homework question - tutors are online