ABSTRACT
This chapter focuses on the neural control of thyroid-stimulating hormone (TSH) release by adenohypophysial cells as well as the neuroendocrine integration involved in regulating the brain-pituitary-thyroid axis. A population of cells of the pars anterior that stain with basic dyes synthesize and secrete thyrotropin into blood for delivery to the thyroid gland. The actions of TSH on the cells of the thyroid gland are to promote the cellular uptake of iodide ions and the production/release of the iodide-containing thyroid hormones. The biological actions of thyroid hormones involve a general stimulation of cellular metabolism and oxygen utilization by a majority of the cells in adult animals. An animal’s perception of the external ambient temperature is a major factor controlling the pituitary-thyroid axis. Secretory products of the thyroid gland exert a closed-loop inhibitory feedback that adjusts the release of TSH into blood to maintain homeostasis.
