Circumventricular organs

Circumventricular Organs (CVOs) are structures in the brain that are characterized by their position around the ventricular system and their extensive vascularization. They are part of the neuroendocrine system and play a crucial role in the homeostasis of the body.

Overview

CVOs are unique in that they are located in the brain but lack a blood-brain barrier, which allows them to directly interact with substances in the bloodstream. This unique feature allows them to perform essential functions such as the detection of systemic changes in blood composition, the regulation of thirst and hunger, and the modulation of body temperature and blood pressure.

Classification

CVOs can be classified into two categories: sensory and secretory.

Sensory CVOs

Sensory CVOs, also known as circumventricular sensory organs, are responsible for detecting changes in the body's internal environment. They include the organum vasculosum of the lamina terminalis (OVLT), the subfornical organ (SFO), and the area postrema (AP).

Secretory CVOs

Secretory CVOs, also known as circumventricular secretory organs, are involved in the secretion of hormones into the bloodstream. They include the median eminence, the pineal gland, and the subcommissural organ (SCO).

Function

CVOs play a crucial role in maintaining the body's homeostasis. They are involved in a variety of physiological processes, including the regulation of water balance, energy metabolism, body temperature, and blood pressure. They also play a role in the body's response to stress and inflammation.

Clinical Significance

Due to their unique position and function, CVOs are implicated in a variety of diseases and conditions. For example, they can be affected by systemic inflammation, leading to changes in behavior and physiological responses. They are also involved in the regulation of body weight, and their dysfunction can contribute to obesity and other metabolic disorders.

See Also

• Blood-brain barrier
• Neuroendocrine system
• Homeostasis

Circumventricular organs gallery

• CVO-NHO Humanos
  CVO-NHO Humanos