Glomusceller

Glomusceller are specialized cells that play a role in thermoregulation and blood pressure regulation. They are part of the glomus bodies, which are small, highly vascularized structures found in various locations throughout the body. The most prominent glomus bodies are located in the skin, particularly in the fingertips, palms, soles, and ears, where they are crucial for controlling blood flow to the extremities and thus conserving or dissipating heat. They are also found in the carotid bodies and aortic bodies, which are chemoreceptors that monitor oxygen, carbon dioxide, and pH levels in the blood.

Histologically, glomus cells are characterized by their abundant eosinophilic cytoplasm and round nuclei. They are arranged in nests or cords and are surrounded by an abundant capillary network. The precise origin of glomus cells is still debated, with theories suggesting they arise from smooth muscle cells, pericytes, or even neural crest cells.

The function of glomus cells in the skin is mediated by arteriovenous anastomoses. When the body needs to conserve heat, glomus cells contract, closing off these anastomoses and reducing blood flow to the skin surface. Conversely, when the body needs to dissipate heat, the glomus cells relax, opening the anastomoses and increasing blood flow to the skin. This mechanism helps maintain core body temperature. In the carotid and aortic bodies, glomus cells are involved in sensing changes in blood gas levels and transmitting signals to the nervous system, which then adjusts breathing rate and heart rate accordingly. Tumors originating from glomus cells are known as glomus tumors or glomangiomas and typically occur in the extremities.