Beta-1 receptors are a type of adrenergic receptor found primarily in the heart. They play a crucial role in regulating heart rate and contractility by responding to hormones like epinephrine and norepinephrine. When activated, these receptors increase heart rate and the force of heart contractions, which helps the body respond to stress or physical activity. In addition to their role in the heart, Beta-1 receptors are also present in the kidneys, where they influence the release of the enzyme renin. This process is important for regulating blood pressure and fluid balance in the body. Overall, Beta-1 receptors are essential for maintaining cardiovascular function.