He hypothesized that these compounds would lower the heart's oxygen consumption by interfering with the effects of catecholamines. His plan was to create a drug that would decrease the heart's requirement for oxygen.
Black focused on developing a drug that would relieve the pain of angina pectoris, which results from oxygen deprivation in the heart. In the early 1960s, James Black, a Scottish pharmacologist, and associates of his at the Imperial Chemical Industries (ICI) in Great Britain were working on a series of β-adrenergic blocking compounds, pronethalol and propranolol. These findings were soon to be a foundation for further research into drug development. Ahlquist published a seminal paper concluding his findings, that there were two distinct receptors for catecholamine drugs, and they caused different responses in the heart muscle. The discovery of β-blockers reaches back to more than 100 years ago, when early investigators came up with the idea that catecholamines were binding selectively to receptor-like structures and that this was the cause of their pharmacological actions. The β-blockers are an immensely important class of drugs due to their high prevalence of use.
