Adrenaline (Epinephrine)

Adrenaline is a hormone belonging to the catecholamine family. It is the primary hormone of the adrenal medulla and chromaffin tissue outside the adrenal glands. Adrenaline plays a role in mediating stress responses.

Its effects are mediated through its influence on α- and β-adrenergic receptors and largely coincide with the effects of sympathetic nervous system activation (dilation of pupils, increased heart rate and strength of heart contractions, regulation of blood vessel tone, elevation of blood pressure, increased breathing rate and depth, stimulation of the central nervous system, and more).

Adrenaline intensifies the breakdown of lipids (lipolysis) and glycogen in muscles and the liver. In high concentrations, it enhances protein catabolism and increases the number of blood formed elements, leading to improved blood clotting ability. In moderate concentrations, it participates in the body’s adaptation to physical loads. Prolonged exposure to adrenaline leads to increased size (functional hypertrophy) of the myocardium and skeletal muscles.

The prolonged presence of high adrenaline concentrations results in intensified protein catabolism, decreased muscle mass and strength, weight loss, and exhaustion during distress.