Sleep variables are unaltered by zolantidine in rats: are histamine H2-receptors not involved in sleep regulation?

Brain Res Bull. 1990 Aug;25(2):229-31. doi: 10.1016/0361-9230(90)90065-8.


The effects of the H1-receptor antagonist diphenhydramine and the brain-penetrating H2-receptor antagonist zolantidine were studied in rats implanted for chronic sleep recordings. Diphenhydramine (1.0-4.0 mg/kg) significantly increased slow wave sleep and decreased wakefulness. Zolantidine (0.25-8.0 mg/kg) had no significant effects on any of the sleep parameters examined. One possibility is that zolantidine did not enter the brain in sufficient concentration to produce significant changes on sleep and wakefulness. Another possibility is that blockade of H2-receptor involved parts of the brain other than those implicated in the sleep-wake cycle. The feasibility remains that H2-receptors are not involved in sleep regulation. The absence of selective, brain-penetrating H2-receptor agonists precludes a more detailed analysis of the role of this subtype of receptor in the control of sleep and wakefulness.

MeSH terms

  • Animals
  • Benzothiazoles
  • Diphenhydramine / pharmacology
  • Dose-Response Relationship, Drug
  • Histamine H2 Antagonists / pharmacology*
  • Male
  • Phenoxypropanolamines
  • Piperidines / pharmacology*
  • Rats
  • Rats, Inbred Strains
  • Receptors, Histamine H2 / drug effects
  • Receptors, Histamine H2 / physiology*
  • Reference Values
  • Sleep / drug effects*
  • Thiazoles / pharmacology*
  • Time Factors
  • Wakefulness / drug effects


  • Benzothiazoles
  • Histamine H2 Antagonists
  • Phenoxypropanolamines
  • Piperidines
  • Receptors, Histamine H2
  • Thiazoles
  • Diphenhydramine
  • zolantidine