 Today we know that about 1,000 receptors in the human body belong to this same family.The importance of this is that all of these receptors use the same basic mechanisms so that pharmaceutical researchers now understand how to effectively target the largest receptor family in the human body.Today, as many as 30 to 50 percent of all prescription drugs are designed to "fit" like keys into the similarly structured locks of Lefkowitz' receptors—everything from anti-histamines to ulcer drugs to beta blockers that help relieve hypertension, angina and coronary disease.