Anatomy and Physiology Resource Site

9.2 - Major Endocrine Glands

The major endocrine organs work together to maintain homeostasis and regulate body functions.

Endocrine glands can be stimulated in three ways:

Hormonal - Tropic hormones from other endocrine tissues (Often rhythmic secretion)
Humoral - Blood levels of ions or nutrients (Feedback control)
Neural - Direct stimulation by the nervous system

The following is a brief overview of the major endocrine glands and their functions.

Table 9.1 - Major endocrine glands

Gland	Hormone(s)	Function(s)
Adrenal Cortex	Corticosteroids	Increase blood glucose and bloos pressure (Na+ reabsorption in kidneys)
Adrenal Medulla	Epinepherine and Norepinepherine	Increase energy consumption through increased metabolism and blood glucose; increased blood pressure (vasoconstriction)
Gonads	Androgens (males) and estrogens (females)	Support the development of gametes and secondary sex characteristics
Hypothalamus	Releasing and inhibiting hormones; Oxytocin and ADH (released by the posterior pituitary)	Regulate production of hormones in the anterior pituitary; See posterior pituitary
Pancreas	Insulin and glucagon	Regulate blood glucose levels
Parathyroid	Parathyroid hormone (PTH)	Increase blood calcium levels
Pineal	Melatonin	Biological day/night and seasonal cycles
Pituitary (anterior)	GH, PRL, FSH, LH, TSH, ACTH	Various; see module 9.5
Pituitary (posterior)	Oxytocin, ADH	See module 9.5
Thymus	Thymosin	Immunocompetency in T lymphocytes
Thyroid	T3, T4, Calcitonin	T3 and T4: stimulates metabolism. Calcitonin: decreases blood calcium levels

Endocrine organ locations

By National Cancer Institute - SEER training modules via Wikimedia Commons

Figure 9.2.1 - Locations of the major endocrine organs