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Rats show unimpaired learning within minutes after recovery from single bolus propofol anesthesia

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To examine the learning ability of rats shortly after recovery from a bolus dose of propofol by assessing learning on a swim-to-platform task. Also, muscarinic blockade was used as a pharmacological test of whether learning shortly after propofol anesthesia resembles normal learning.


Propofol anesthetized rats (15–20 mg · kg−1 iv) were trained on a swim-to-platform task five to seven minutes after recovering from surgical anesthesia and tested two to three hours later. In addition, the muscarinic antagonist scopolamine hydrobromide (5 mg · kg−1 sc) was given to a subgroup of rats before testing. During 10 trials, the number of times a given rat took 10 sec or longer to locate and climb onto a visible platform was tabulated and counted as errors.


When trained shortly after recovery from the anesthetic, propofol anesthetized rats made 3.2 ± 0.4 compared with 1.0 ± 0.1 errors in controls (P < 0.0001). Two to three hours later both groups performed equally well. Rats trained after propofol anesthesia and given scopolamine before testing made 0.7 ± 0.5 errors and performed as well as normal controls, 1.2 ± 0.2 errors when subjected to the same procedures without propofol anesthesia, and better than scopolamine-treated untrained rats, 5.5 ± 0.7 errors, (P < 0.05).


Training five to seven minutes after recovery from propofol anesthesia resulted in normal retention of the swim-to-platform task. It also produced the same resistance to the disruptive effects of scopolamine as did training in rats that were not anesthetized. Thus, the ability to learn recovers rapidly after propofol anesthesia induced by a single intravenous bolus dose.



Examiner la capacité d’apprendre des rats, peu après la récupération d’une anesthésie avec une dose bolus de propofol, en évaluant comment ils apprennent à nager vers une plate-forme. De plus, utiliser le blocage muscarinique en qualité de test pharmacologique de l’apprentissage, et voir si c’est comparable à un apprentissage normal.


Des rats ayant reçu une anesthésie au propofol (15–20 mg · kg−1 iv) ont été entraînés à nager vers une plateforme, cinq à sept minutes après la récupération de l’anesthésie et ont été testés de nouveau deux à trois heures plus tard. La scopolamine, antagoniste muscarinique, a été administrée (5 mg · kg−1sc) à un sous-groupe de rats avant les essais. Pendant les 10 essais, le nombre de fois qu’un rat donné prenait 10 s ou plus pour atteindre une plate-forme visible et y grimper ont été considérées comme des erreurs.


Les rats entraînés peu après la récupération de l’anesthésie au propofol ont fait 3.2 ± 0.4 erreurs et les rats témoins, 1.0 ± 0.1 erreur (P < 0.0001). Deux ou trois heures plus tard, les performances étaient égales pour les rats des deux groupes. Les rats entraînés après l’anesthésie et qui ont reçu de la scopolamine avant les essais ont fait 0.7 ± 0.5 erreur, faisant aussi bien que les rats témoins, 1.2 ± 0.2 erreur, soumis aux mêmes épreuves sans anesthésie au propofol, et mieux que les rats non entraînés mais traités à la scopolamine, 5.5 ± 0.7 erreurs (P < 0.05).


Lentraînement, cinq à sept minutes après la récupération de l’anesthésie au propofol, a permis une rétention normale de l’apprentissage qui consistait à nager vers une plate-forme, Cela a produit aussi la même résistance aux effets perturbateurs de la scopolamine que l’entraînement des rats non anesthésiés. Ainsi, la capacité d’apprendre est rapidement récupérée après l’anesthésie au propofol induite avec une dose unique en bolus intraveineux.


  1. 1

    Kay B, Rolly G. ICI 35868, a new intravenous induction agent. Acta Anaesthesiol Belg 1977; 28: 303–16.

  2. 2

    Bryson HM, Fulton BR, Faulds D. Propofol. An update of its use in anaesthesia and conscious sedation. Drugs 1995; 50: 513–59.

  3. 3

    Fulton B, Sorkin EM. Propofol. An overview of its pharmacology and a review of its clinical efficacy in intensive care sedation. Drugs 1995; 50: 636–57.

  4. 4

    Polster MR, Gray PA, O’Sullivan G, McCarthy RA, Park GR. Comparison of the sedative and amnesic effects of midazolam and propofol. Br J Anaesth 1993; 70: 612–6.

  5. 5

    Veselis RA, Reinsel RA, Wroski M, Marino P, Tong WP, Bedford RF. EEG and memory effects of lowdose infusions of propofol. Br J Anaesth 1992; 69: 246–54.

  6. 6

    Griffiths D, Jones JG. Awareness and memory in anaesthetized patients (Editorial). Br J Anaesth 1990; 65: 603–6.

  7. 7

    Bethune DW, Ghosh S, Gray B, et al. Learning during general anaesthesia: implicit recall after methohexitone or propofol infusion. Br J Anaesth 1992; 69: 197–9.

  8. 8

    Sanou J, Goodall G, Capuron L, Bourdalle-Badie C, Maurette, P. Cognitive sequelae of propofol anaesthesia. Neuro Report 1996; 7: 1130–2.

  9. 9

    Vanderwolf CH. Near total loss of ‘learning’ and ‘memory’ as a result of combined cholinergic and serotonergic blockade in the rat. Behav Brain Res 1987; 23: 43–57.

  10. 10

    Whishaw IQ. Cholinergic receptor blockade in the rat impairs locale but not taxon strategies for place navigation in a swimming pool. Behav Neurosci 1985; 99: 979–1005.

  11. 11

    Vanderwolf CH. Cerebral activity and behavior: control by central cholinergic and serotonergic systems. Int Rev Neurobiol 1988; 30: 225–340.

  12. 12

    Vanderwolf CH. Anti-muscarinic drug effects in a swim-to-platform test: dose-response relations. Behav Brain Res 1991; 44: 217–9.

  13. 13

    Buresova O, Bures J, Bohdanecky Z, Weiss T. Effect of atropine on learning, extinction, retention and retrieval in rats. Psychopharmacology 1964; 5: 255–63.

  14. 14

    Herz A. Über die Wirkung von scopolamin, benactyzin, und atropin auf das verhalten der ratte. Naunyn Schmiedebergs Arch Pharmacol 1959; 236: 110–1.

  15. 15

    DeVietti TL, Pellis SM, Pellis VC, Teitelbaum P. Previous experience disrupts atropine-induced stereotyped “trapping” in rats. Behav Neurosci 1985; 99: 1128–41.

  16. 16

    Vanderwolf CH. Behavior-related cortical activity and swim-to-platform performance in the aged rat. Behav Brain Res 1992; 52: 153–8.

  17. 17

    Morris R. Developments of a water-maze procedure for studying spatial learning in the rat. J Neurosci Methods 1984; 11: 47–60.

  18. 18

    Caldji C, Vanderwolf CH. The effects of different types of pre-training on the rat’s retention performance in a swim-to-platform task following administration of scopolamine. Behav Brain Res 1996; 80: 217–20.

  19. 19

    Vanderwolf CH. Effects of water temperature and core temperature on rat’s performance in a swim-top-lat-form test. Behav Brain Res 1991; 44: 105–6.

  20. 20

    Vanderwolf CH, Penava D. Potentiation of the effects of antimuscarinic drugs on behavior by serotonin depletion: specificity and relation to learning and memory.In: Levin ED, Decker MW, Butcher LL (Eds.). Neurotransmitter Interactions and Cognitive Function. Boston: Birkhäuser, 1992: 257–76.

  21. 21

    Siegel S. Nonparametric Statistics for the Behavioral Sciences. New York: McGraw Hill, 1956.

  22. 22

    Fassoulaki A, Farinotti R, Mantz J, Desmonts JM. Does tolerance develop to the anaesthetic effects of propofol in rats? Br J Anaesth 1994; 72: 127–8.

  23. 23

    Sbyr M-H, Tang C-H, Kuo TBJ, Pan WHT, Tan PPC, Chan SHH. Power spectral analysis of the electroencephalographic and hemodynamic correlates of propofol anesthesia in the rat: intravenous bolus injection. Neurosci Lett 1993; 153: 161–4.

  24. 24

    Liu T, Fay T, Deitrich RA. Behavioral effects and pharmacokinetics of propofol in rats selected for differential ethanol sensitivity. Alcohol Clin Exp Res 1995; 19: 874–8.

  25. 25

    Dolin SJ, Smith MB, Soar J, Morris PJ. Does glycine antagonism underlie the excitatory effects of methohexitone and propofol? Br J Anaesth 1992; 68: 523–6.

  26. 26

    Orser B. Propofol-induced neuroexcitation and receptor desensitization (Editorial). Can J Anaesth 1994; 41: 366–71.

  27. 27

    Reddy RV, Moorthy SS, Dierdorf SF, Deitch RD Jr, Link L. Excitatory effects and electroencephalographic correlation of etomidate, thiopental, methohexital and propofol. Anesth Analg 1993; 77: 1008–11.

  28. 28

    Kits CR, Scoates PJ, Puil E. Opisthotonos following propofol: a nonepileptic perspective and treatment strategy. Can J Anaesth 1994; 41: 414–9.

  29. 29

    Vanderwolf CH, Baker GB. The role of brain noradrenaline in cortical activation and behavior: a study of lesions of the locus coeruleus, medial thalamus and hippocampus-neocortex and of muscarinic blockade in the rat. Behav Brain Res 1996; 78: 225–34.

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Correspondence to Christopher G. Engeland.

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Supported by an operating grant to C.H. Vanderwolf from NSERC.

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Engeland, C.G., Vanderwolf, C.H. & Gelb, A.W. Rats show unimpaired learning within minutes after recovery from single bolus propofol anesthesia. Can J Anesth 46, 586 (1999). https://doi.org/10.1007/BF03013552

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  • Scopolamine
  • Training Trial
  • Retention Testing
  • Disruptive Effect
  • Behav Brain