ABSTRACT
The major steps in designing a drug to treat a particular disease state are deceptively clear. First, find a therapeutic target that can be manipulated to ameliorate the condition, and then find a specific drug that will alter the function of the target appropriately. Ideally, the drug will not provoke deleterious side effects and will work as well in vivo as it does in vitro. Alternatively, one may already have a partially useful drug, but need to know its target and mechanism of action so as to improve its efficacy. A fundamental requirement for making progress in any of these steps is the need to be able to define the exact nature of the drug-receptor interaction, and the effect it has on receptor function.
