Histamine receptor H1 (HRH1) (HRH1)

The Histamine receptor H1 (HRH1) is a G protein-coupled receptor that mediates the diverse physiological actions of histamine in both the periphery and the central nervous system (CNS). In peripheral tissues, HRH1 activation leads to smooth muscle contraction, increased vascular permeability, and the stimulation of sensory nerves, which are central to allergic responses such as rhinitis, urticaria, and anaphylaxis [1.2.1, 1.4.1]. In the CNS, the receptor is primarily involved in the regulation of the sleep-wake cycle, where it promotes wakefulness and alertness [1.4.1, 1.5.4]. Amitriptyline, a tricyclic antidepressant, is a potent antagonist of the H1 receptor, and this interaction is largely responsible for the drug's sedative properties and its potential to cause weight gain [1.1.1, 1.3.2]. While H1 antagonism is the primary mechanism for anti-allergy medications, in the context of antidepressants like amitriptyline, it often manifests as a side effect that can impact patient compliance [1.3.1, 1.5.2]. Understanding the H1 receptor's distribution and binding profile is essential for managing the therapeutic and adverse effects of drugs that target the histaminergic system [1.4.5, 1.5.4].

Other names

H1-RH1RHH1RhisH1Histamine H1 receptor

Antagonist (Inverse agonist)