The pituitary gland is divided into two lobes - the anterior lobe and the posterior lobe. The anterior lobe produces and secretes hormones that act on various target organs. Some of the key hormones secreted by the anterior pituitary include:
| Hormone |
Function |
| Growth hormone (GH) |
Stimulates growth and cell reproduction |
| Thyroid stimulating hormone (TSH) |
Regulates thyroid gland function and thyroid hormone production |
| Adrenocorticotropic hormone (ACTH) |
Stimulates the adrenal glands to produce cortisol |
| Follicle stimulating hormone (FSH) and luteinizing hormone (LH) |
Regulate gonadal function and sex hormone production |
Meanwhile, the posterior pituitary stores and releases two hormones produced by the hypothalamus -
oxytocin and
vasopressin. Oxytocin stimulates uterine contractions during childbirth and milk let-down during breastfeeding. Vasopressin, also known as antidiuretic hormone, regulates fluid balance and blood pressure.
The pituitary gland works in close conjunction with the
hypothalamus, which connects the endocrine system with the nervous system. The hypothalamus produces hormones that either stimulate or inhibit hormone production in the anterior pituitary. This feedback loop allows the body to precisely calibrate its complex hormonal systems.
What happens when the pituitary gland malfunctions? Abnormalities in pituitary hormone secretion can lead to various disorders:
| Disorder |
Description |
| Pituitary adenomas |
Benign tumors that cause overproduction or underproduction of hormones |
| Pituitary apoplexy |
Sudden hemorrhage and infarction of the pituitary gland |
| Hypopituitarism |
Underactivity of the pituitary leading to hormone deficiencies |
| Hyperpituitarism |
Overactivity of the pituitary resulting in excess hormone secretion |
| Diabetes insipidus |
Caused by vasopressin deficiency leading to abnormal urine |