Advertisement

Psychopharmacology

, Volume 156, Issue 4, pp 417–426 | Cite as

Comparative effects of melatonin, zolpidem and diazepam on sleep, body temperature, blood pressure and heart rate measured by radiotelemetry in Wistar rats

  • François Mailliet
  • Paul Galloux
  • Denise Poisson
Original Investigation

Abstract.

Rationale: The role of melatonin (MLT) in mediating the sleep–wake cycle has been previously suspected of indicating that this substance could be a candidate for a new generation of hypnotics. Objectives: We investigated whether MLT acted as a sleep promoter or a modulator of sleep temporal timing related to cardiovascular and body temperature (Tb) adaptations to sleep induction. The pharmacological effects of MLT on sleep were compared with zolpidem (ZP) and diazepam (DZ). Methods: The radiotelemetry system was used to record the electrocorticogram [slow wave sleep (SWS), paradoxical sleep (PS)], Tb, blood pressure and heart rate in six Wistar rats. DZ (3 mg/kg and 6 mg/kg), ZP (1, 3, 5 and 10 mg/kg) and MLT (2.5 and 5 mg/kg) were delivered intraperitoneally during light (L) and dark (D) periods. Results: MLT increased the number of sleep cycles (L: 30%, D: 110%) and total duration (P<0.05) of PS (L: 70%, D: 150%). In return, ZP (10 mg/kg) presented no effect during L but increased total (40%) and mean duration (37%) of SWS during the D period. DZ modified mean duration of SWS (L: –27%, D: +26%) and increased total duration of SWS (+47%). ZP and DZ induced a more pronounced decrease in Tb than MLT but only DZ induced tachycardia and hypertension. Conclusions: We showed that MLT could not promote sleep and its cardiovascular adaptations despite hypothermia, but modulated the period of ultradian sleep cycles. DZ and ZP promoted sleep and induced hypothermia during the D period. Only DZ disrupted sleep architecture and induced adverse effects on cardiovascular parameters.

Hypnotics Sleep Polysomnography Radiotelemetry Wistar rat 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag 2001

Authors and Affiliations

  • François Mailliet
    • 1
  • Paul Galloux
    • 2
  • Denise Poisson
    • 2
  1. 1.UMR "INRA-CNRS-Université de Tours" 6073, Physiologie de la Reproduction et des Comportements, 37380 Nouzilly, France
  2. 2.Department of Neuropharmacology, Faculty of Pharmacy, University of Tours, 31, Avenue Monge, 37200 Tours, France

Personalised recommendations