Pituitary (posterior)

Table of Contents

Other names

posterior pituitary
neurohypophysis

Synopsis

The posterior pituitary, or neurohypophysis, is the back portion of the pituitary gland. Unlike the anterior pituitary, it does not produce hormones itself. Instead, it serves as a storage and release site for two critical hormones that are synthesized in the hypothalamus:

  • Antidiuretic Hormone (ADH), also called vasopressin: Regulates water balance by controlling how much water the kidneys reabsorb, thereby influencing blood pressure and hydration status.

  • Oxytocin: Stimulates uterine contractions during labor, promotes milk ejection during breastfeeding, and influences emotional bonding and social behavior.

These hormones are made in the supraoptic and paraventricular nuclei of the hypothalamus, then transported down nerve fibers (axons) into the posterior pituitary, where they are stored until needed.

The posterior pituitary is part of the neuroendocrine system, and its function is closely tied to signals from the nervous system, particularly in response to stress, blood osmolality, and physical/emotional stimuli.

Medical Information

Posterior pituitary dysfunction can disrupt fluid balance and reproductive processes, most commonly seen in:

  • Diabetes Insipidus (central): Caused by insufficient ADH production or release. Leads to excessive urination (polyuria), intense thirst (polydipsia), dehydration, and electrolyte imbalances.

  • Syndrome of Inappropriate Antidiuretic Hormone (SIADH): Characterized by excessive ADH, causing water retention, low sodium (hyponatremia), and potential neurological symptoms.

  • Oxytocin-related issues: Though rarer, inadequate oxytocin may contribute to labor complications or affect maternal-infant bonding. Oxytocin is also being researched for roles in autism spectrum disorders and social cognition.

Imaging (e.g., MRI of the pituitary) and hormone testing (plasma osmolality, ADH levels, sodium) are used to evaluate posterior pituitary disorders.

Natural Remedies

Hydration and electrolyte support: Especially for those with fluctuating ADH levels. Coconut water, trace minerals, and salt balance are helpful.

Magnesium and potassium: Support nerve signaling and water-electrolyte balance.

Adaptogens (e.g., ashwagandha, holy basil): Help regulate stress, which can affect both ADH and oxytocin release.

Omega-3s and vitamin D: Support brain and hypothalamic health, indirectly aiding posterior pituitary signaling.

Mindfulness and social bonding: Hugging, nurturing touch, and even meditation can naturally boost oxytocin levels.

Sleep and circadian rhythm: ADH secretion follows a circadian pattern—sleep disruption can impair fluid regulation.