Histamine H-3 receptor antagonists

The histamine H-3 receptor provides a negative feedback mechanism for the r elease and synthesis of histamine. On non-histaminergic neurones the H-3 re ceptor regulates the release of many other neurotransmitters. Blockade of s timulated H-3 receptors results in the release of endogenous neurotransmitt ers. Possible indications for a histamine H-3 receptor antagonist include a ttention-deficit hyperactivity disorder (ADI-ID), epilepsy, Alzheimer's dis ease, narcolepsy, epilepsy, obesity, schizophrenia and respiratory diseases such as allergic rhinitis. Current H-3 receptor antagonists fall into two classes, imidazole-containing and non-imidazole compounds, with there being far more examples of the Former. The development of imidazole antagonists has produced the compound GT-2331 (Perceptin(TM) Gliatech), which has succe ssfully passed early stage clinical trials. The search for non-imidazole an tagonists is a burgeoning area, which may profit from the recent cloning of a human H-3 receptor.