Pars intermedia: Difference between revisions

Latest revision as of 14:11, 21 February 2025

Pars Intermedia[edit]

Diagram of the pituitary gland showing the pars intermedia.

The pars intermedia is a part of the pituitary gland, which is an important endocrine organ located at the base of the brain. The pituitary gland is divided into three distinct parts: the anterior pituitary (adenohypophysis), the posterior pituitary (neurohypophysis), and the pars intermedia.

Structure[edit]

The pars intermedia is a thin layer of tissue situated between the anterior and posterior lobes of the pituitary gland. It is often considered a part of the anterior pituitary due to its embryological origin from the Rathke's pouch.

Histologically, the pars intermedia is composed of basophilic cells and colloid-filled cysts. These cysts are remnants of the Rathke's pouch and are characteristic of this region.

Function[edit]

The primary function of the pars intermedia is the production of melanocyte-stimulating hormone (MSH). MSH is involved in the regulation of skin pigmentation in some animals, although its role in humans is less clear. In humans, the pars intermedia is often rudimentary and its function is not as prominent as in other species.

Clinical Significance[edit]

In some animals, the pars intermedia plays a significant role in the regulation of melanin production and can affect skin color changes. Disorders of the pars intermedia can lead to conditions such as Cushing's disease in horses, where there is an overproduction of hormones due to pituitary dysfunction.

In humans, the pars intermedia is not commonly associated with major endocrine disorders, but its role in the overall function of the pituitary gland is still a subject of research.

Related Pages[edit]

@@ Line 1: / Line 1: @@
-{{Short description|Section of the pituitary gland}}
+== Pars Intermedia ==
-{{Use dmy dates|date=October 2023}}
-The '''pars intermedia''' is a part of the [[pituitary gland]], which is an important endocrine organ located at the base of the brain. The pituitary gland is divided into three distinct parts: the [[anterior pituitary]] (adenohypophysis), the [[posterior pituitary]] (neurohypophysis), and the pars intermedia. The pars intermedia is situated between the anterior and posterior lobes of the pituitary gland.
+[[File:Gray1181.png|thumb|right|Diagram of the pituitary gland showing the pars intermedia.]]
-==Structure==
+The '''pars intermedia''' is a part of the [[pituitary gland]], which is an important endocrine organ located at the base of the brain. The pituitary gland is divided into three distinct parts: the [[anterior pituitary]] (adenohypophysis), the [[posterior pituitary]] (neurohypophysis), and the pars intermedia.
-The pars intermedia is a thin layer of cells that is often considered part of the anterior pituitary. It is composed of [[basophilic cells]] and is less developed in humans compared to other species. In some animals, such as fish and amphibians, the pars intermedia is more prominent and plays a significant role in physiological processes.
-[[File:Human pituitary gland.jpg|thumb|right|Diagram of the human pituitary gland showing the pars intermedia.]]
+== Structure ==
-==Function==
+The pars intermedia is a thin layer of tissue situated between the anterior and posterior lobes of the pituitary gland. It is often considered a part of the anterior pituitary due to its embryological origin from the [[Rathke's pouch]].
-The primary function of the pars intermedia is the production of [[melanocyte-stimulating hormone]] (MSH), which is involved in the regulation of skin pigmentation. MSH stimulates the production and release of [[melanin]] by melanocytes in the skin and hair. In humans, the role of MSH is less pronounced, but it is still involved in the regulation of appetite and energy homeostasis.
-==Development==
+[[File:Pituitary_gland_histology_2014.jpg|thumb|left|Histological section of the pituitary gland showing the pars intermedia.]]
-During embryonic development, the pituitary gland forms from two distinct ectodermal tissues: the [[Rathke's pouch]] and the infundibulum. The pars intermedia originates from Rathke's pouch, which also gives rise to the anterior pituitary. As development progresses, the pars intermedia becomes a thin layer of cells sandwiched between the anterior and posterior lobes.
-==Clinical Significance==
+Histologically, the pars intermedia is composed of basophilic cells and colloid-filled cysts. These cysts are remnants of the Rathke's pouch and are characteristic of this region.
-In humans, disorders of the pars intermedia are rare. However, in some animals, such as horses, dysfunction of the pars intermedia can lead to conditions like [[Equine Cushing's disease]], also known as pituitary pars intermedia dysfunction (PPID). This condition is characterized by an overproduction of hormones, leading to symptoms such as increased coat length, weight loss, and laminitis.
+== Function ==
+The primary function of the pars intermedia is the production of [[melanocyte-stimulating hormone]] (MSH). MSH is involved in the regulation of skin pigmentation in some animals, although its role in humans is less clear. In humans, the pars intermedia is often rudimentary and its function is not as prominent as in other species.
+== Clinical Significance ==
+In some animals, the pars intermedia plays a significant role in the regulation of [[melanin]] production and can affect skin color changes. Disorders of the pars intermedia can lead to conditions such as [[Cushing's disease]] in horses, where there is an overproduction of hormones due to pituitary dysfunction.
+In humans, the pars intermedia is not commonly associated with major endocrine disorders, but its role in the overall function of the pituitary gland is still a subject of research.
+== Related Pages ==
-==Related pages==
 * [[Pituitary gland]]
 * [[Anterior pituitary]]
 * [[Posterior pituitary]]
 * [[Melanocyte-stimulating hormone]]
-* [[Endocrine system]]
+* [[Rathke's pouch]]
 [[Category:Endocrine system]]
-[[Category:Human anatomy]]
+[[Category:Pituitary gland]]