Histamine and Delirium: Current Opinion

This study indicated that switch from H2 blockers to PPIs reduced delirium and, thus, providing an appropriate strategy to combat drug-induced delirium using antiulcer drugs (Fujii et al., 2012). The ventrolateral preoptic nucleus is a sleep-promoting nucleus located in the basal forebrain. A commonly used intravenous anesthetic, propofol, had been reported to induce sleep and augment the firing rate of neurons in ventrolateral GABAergic preoptic nucleus, but the underlining mechanism is yet to be clearly determined. Interestingly, the propofol-induced inhibition of inhibitory postsynaptic currents on noradrenalin-inhibited neurons have been shown to be mediated by histaminergic H1 and H2 receptors (Liu et al., 2017). Opioids and Histamine Interactions An interaction between histaminergic and opioidergic systems within the CNS was proposed three decades ago, suggesting that analgesia produced by opioids may be associated with release of histamine and the stimulation of histamine receptors at the supraspinal (central) level (Nishibori et al., 1985). Many more recent studies have shown that histamine receptor antagonists can modulate the analgesic action of opioids, however, the site and mode of action of this interaction differs between the spinal or supraspinal level, and depends on the subtype of histamine receptor (Mobarakeh et al., 2002, 2006, 2009; Stein et al., 2016). A series of studies have also shown than in H1R and H2R KO mice, morphine-induced antinociception was ...
Source: Frontiers in Pharmacology - Category: Drugs & Pharmacology Source Type: research