Human Hemoglobin (Hb)

Human hemoglobin is a globular metalloprotein found in red blood cells, primarily responsible for the transport of oxygen from the lungs to tissues and facilitating the return transport of carbon dioxide from tissues back to the lungs. It also plays a role in nitric oxide metabolism and regulation of vascular tone. It has a quaternary structure composed of four subunits: two alpha (α) chains and two beta (β) chains in adults. Each subunit contains a globin protein chain and a heme group, which includes an iron (Fe²⁺) ion. Genetic variants like HbS (Sickle cell) can cause significant clinical symptoms.

Other names

Hemoglobin AHbAHemoglobin FHbFHemoglobin A2HbA2Globin

Drugs primarily manage consequences of hemoglobin dysfunction (e.g., Hydroxyurea increases HbF levels). Direct hemoglobin-targeting drugs are limited.