What is the Difference Between Hypothalamus and Pituitary Gland

The key difference between hypothalamus and pituitary gland is that hypothalamus is an almond-sized gland located below the thalamus, which helps to secrete hormones responsible for stimulating or inhibiting the production of hormones in the anterior pituitary, while pituitary gland is a pea-sized gland attached to the hypothalamus that stores hormones from the hypothalamus and releases them into the bloodstream.

Hypothalamus and pituitary gland complex can be described as the command centre of the human endocrine system. This complex normally secretes several hormones that directly produce responses in target tissues. Moreover, this centre also produces hormones that regulate the synthesis and secretion of hormones of other glands.

CONTENTS

1. Overview and Key Difference
2. What is Hypothalamus
3. What is Pituitary Gland
4. Similarities – Hypothalamus and Pituitary Gland
5. Hypothalamus vs Pituitary Gland in Tabular Form
6. Summary – Hypothalamus vs Pituitary Gland

What is Hypothalamus?

Hypothalamus is an almond-sized gland located below the thalamus and just above the brainstem. All vertebrates’ brains have a hypothalamus. Hypothalamus is a part of the limbic system and contains a number of small nuclei with a variety of functions. The primary function of the hypothalamus is to maintain homeostasis in the body. It secretes ‘releasing hormones’ and ‘inhibiting hormones,’ which stimulate or inhibit the production of hormones in the anterior pituitary. A specialized neuron clusters called neurosecretory cells are present in the hypothalamus. They produce the hormones called antidiuretic hormone (ADH) and oxytocin (OXT). These hormones are later transported to the pituitary, where they are stored for later release.

The hypothalamus regulates certain metabolic processes and other activities of the autonomic nervous system. It synthesizes and secretes certain neurohormones called releasing hormones or hypothalamic hormones. These hormones, in turn, stimulate or inhibit the secretion of hormones from the pituitary gland. Furthermore, the hypothalamus controls the temperature of the body and hunger. In addition to that, the hypothalamus also controls important aspects of parenting and attachment behaviours, thirst, fatigue, sleep, and circadian rhythms.

What is Pituitary Gland?

Pituitary gland is a pea-sized gland and reddish-gray body attached to the hypothalamus that stores hormones from the hypothalamus and releases them into the bloodstream. The pituitary gland consists of an anterior lobe and a posterior lobe. Each of these lobes has distinct functions. The anterior lobe secretes hormones that regulate a wide variety of bodily functions. The anterior pituitary lobe has five types of cells (somatotrophs, gonadotrophs, lactotrophs, corticotrophs, and thyrotrophs) that secrete seven hormones, including human growth hormone (hGH), thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), adrenocorticotropic hormone (ACTH) and melanocyte-stimulating hormone (MSH). The posterior lobe stores and releases only two hormones named oxytocin and antidiuretic hormone (ADH) or vasopressin.

The main function of the pituitary gland is to produce and release several hormones that help the human body to carry out important functions, including growth, metabolism, reproduction, response to stress or trauma, lactation, water and sodium balance, and labor and childbirth.

What are the Similarities Between Hypothalamus and Pituitary Gland?

• Hypothalamus and pituitary gland complex is the command centre of the human endocrine system.
• Both glands are located in the brain.
• These glands are attached to each other.
• Dysfunction of both glands is responsible for numerous disorders.

What is the Difference Between Hypothalamus and Pituitary Gland?

Hypothalamus is an almond-sized gland located below the thalamus and secretes releasing hormones and inhibiting hormones that stimulate or inhibit the production of hormones in the anterior pituitary, while pituitary gland is a pea-sized gland attached to the hypothalamus and stores hormones from the hypothalamus and releases them into the bloodstream. This is the key difference between hypothalamus and pituitary gland.

The following table summarizes the difference between hypothalamus and pituitary gland.

Summary – Hypothalamus vs Pituitary Gland

Hypothalamus and pituitary gland complex is the command centre of the human endocrine system. Hypothalamus is an almond-sized gland that is located below the thalamus. It secretes releasing hormones and inhibiting hormones that stimulate or inhibit the production of hormones in the anterior pituitary. Pituitary gland is a pea-sized gland attached to the hypothalamus and stores hormones from the hypothalamus and releases them into the bloodstream. This summarizes the difference between hypothalamus and pituitary gland.

Reference:

1. Seladi-Schulman, Jill. “Understanding the Hypothalamus and Its Function.” Healthline, Healthline Media.
2. “Pituitary Gland: What It Is, Function & Anatomy.” Cleveland Clinic.

Image Courtesy:

1. “1806 The Hypothalamus-Pituitary Complex” By OpenStax College – Anatomy & Physiology, Connexions Web site. Jun 19, 2013. (CC BY 3.0) via Commons Wikimedia
2. “1808 The Anterior Pituitary Complex” By OpenStax College – Anatomy & Physiology, Connexions Web site.  Jun 19, 2013. (CC BY 3.0) via Commons Wikimedia