What is the Difference Between Anterior Pituitary and Posterior Pituitary?

The pituitary gland is a small, pea-sized endocrine gland located at the base of the skull, underneath the brain and behind the bridge of the nose. It has two main lobes: the anterior pituitary gland and the posterior pituitary gland, which are joined by pars intermedia. The main differences between the anterior pituitary and the posterior pituitary are:

• Origin: The anterior pituitary (adenohypophysis) is glandular tissue that develops from the digestive tract in the embryo, while the posterior pituitary (neurohypophysis) is neural tissue that derives from the neural ectoderm.
• Hormone Production: The anterior pituitary produces, stores, and releases various hormones, including growth hormone (GH), prolactin (PRL), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and others. The posterior pituitary, on the other hand, does not produce its own hormones but stores and releases two hypothalamic hormones: oxytocin and antidiuretic hormone (ADH).
• Connection to the Hypothalamus: The anterior pituitary is connected to the hypothalamus by short blood vessels, while the posterior pituitary is part of the brain and secretes hormones directly into the bloodstream under the command of the brain.
• Size: The anterior pituitary makes up about 80% of the total weight of the pituitary gland, while the posterior pituitary is smaller.

Comparative Table: Anterior Pituitary vs Posterior Pituitary

The anterior pituitary and posterior pituitary are two distinct lobes of the pituitary gland, which is a small endocrine organ located in the human skull. They have different functions, cellular structures, and hormones they secrete. Here is a table summarizing the differences between the anterior pituitary (adenohypophysis) and the posterior pituitary (neurohypophysis):

The anterior pituitary is responsible for producing and releasing various hormones that regulate functions of other endocrine glands, such as the thyroid gland, adrenal glands, ovaries, and testes. In contrast, the posterior pituitary does not produce hormones; instead, it stores and releases hormones produced by nerve cells in the hypothalamus.