The Beta-1 adrenergic receptor is a type of protein found on the surface of certain cells in the body, particularly in the heart. It plays a crucial role in the body's response to stress by binding to hormones like norepinephrine and epinephrine. When activated, it increases heart rate and the force of heart contractions, helping to pump more blood during stressful situations. These receptors are part of the adrenergic receptor family, which are involved in the sympathetic nervous system response. They are important in regulating cardiovascular functions and are often targeted by medications for conditions like heart failure and hypertension.