The Mongolian gerbil in experimental epilepsy

  • Bertorelli R. 
  • Adami M. 
  • Ongini E. 
Animal Models Relevant to Human Epilepsies

Abstract

The Mongolian gerbil is recognized as a suitable experimental model for studying epileptiform seizures. About 10–20% of the gerbils provided by animal breeders show convulsions when placed in a new laboratory environment or handled for drug administration. In this review, the usefulness of the gerbil is critically evaluated on the basis of the literature available and our experience. Since gerbils often react with seizures in response to external stimuli we utilized a blast of compressed air. Seven gerbils were tested once weekly, for 15 consecutive weeks, and electroencephalographic (EEG) activity was recorded. When the animals were challenged by a blast of compressed air they developed seizures, but with varying intensity and frequency. In the first weeks the majority of gerbils did not show seizures but they began to be susceptible to the stimulus from the 5th or 6th week. Four out of 7 animals proceeded to more severe seizures, characterized by clonic-tonic components. The pattern of behavioral seizures was paralleled by changes in the EEG recording. Altogether, data available indicate that the gerbil model is interesting in ethological studies and may be useful for investigating the mechanisms underlying “spontaneous” seizures. In pharmacology, however, the model has some weaknesses which limit its application in the study of new and established antiepileptic drugs.

Key Words

Mongolian gerbil seizure-susceptibility spontaneous seizure compressed air electroencephalography 

Sommario

Il gerbillo è un piccolo roditore che viene comunemente usato in laboratorio per la sua predisposizione genetica alle convulsioni. Alcuni animali (10%) sviluppano crisi epilettiche spontanee al cambio della gabbia o quando vengono sottoposti a stimoli esterni. In questo lavoro, è stata valutata l'utilità del gerbil, come modello sperimentale per lo studio dell'epilessia, sia in base alla letteratura che all'esperienza degli autori. Sono stati utilizzati gerbilli maschi (Meriones unguiculatus) a cui sono stati applicati elettrodi corticali per la valutazione dell'attività elettroencefalografica (EEG). Gli animali sono stati sottoposti una volta alla settimana, per 15 settimane consecutive, all'esposizione ad un forte getto di aria compressa (5 atm) per 10 sec. La risposta allo stimolo di aria compressa tra i vari animali è stata molto variabile e scarsamente riproducibile. Nelle prime settimane di stimolazione la maggior parte degli animali non ha mostrato segni di convulsioni, mentre dalla quinta-sesta settimana, i gerbilli hanno iniziato ad essere suscettibili allo stimolo, manifestando i primi stadi degli attacchi epilettici, le cosiddette “convulsioni minori”. Quattro animali su sette hanno poi sviluppato le cosiddette “crisi maggiori”, mentre gli altri tre animali si sono attestati sullo stesso livello per diverse settimane. Le crisi epilettiche erano associate a modificazioni del tracciato EEG.

In conclusione, i dati ottenuti dal nostro laboratorio e l'analisi della letteratura indicano che il modello del gerbillo è certamente interessante per capire i meccanismi che sono alla base delle convulsioni spontanee. Tuttavia, in farmacologia, questo modello ha alcuni limiti che lo rendono di difficile applicazione per lo studio di nuovi farmaci antiepilettici.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1]
    Ambrosini M.V., Gambelunghe C., Mariucci G., Bruschelli G., Adami M., Giuditta A.:Sleep-wake variables and EEG power spectra in Mongolian gerbils and Wistar rats. Physiol. Behav., 56:963–968, 1994.PubMedGoogle Scholar
  2. [2]
    Berry K., Wisniewski H.M., Svarzbein I., Baez S.:On the relationship of brain vasculature to production of neurological deficit and morphological changes following acute unilateral common carotid artery ligation in gerbils. J. Neurol. Sci., 25: 75–92, 1975.PubMedGoogle Scholar
  3. [3]
    Cox B., Lomax P.:Brain amines and spontaneous epileptic seizures in the Mongolian gerbil. Pharmacol. Biochem. Behav., 4: 263–267, 1976.PubMedGoogle Scholar
  4. [4]
    Cutler M.G., Mackintosh J.H.:Epilepsy and behaviour of the Mongolian gerbil: and ethological study. Physiol. Behav., 46: 561–566, 1989.PubMedGoogle Scholar
  5. [5]
    Donadio M.F., Kozlowski P.B., Kaplan H., Wisniewski H.M., Majkowski J.:Brain vasculature and induced ischemia in seizure-prone and non-seizure-prone gerbils. Brain Res., 234:263–273, 1982.PubMedGoogle Scholar
  6. [6]
    Frey H.H., Löscher W., Reiche R., Schultz D.:Anticonvulsant potency of common antiepileptic drugs in the gerbil. Pharmacology, 27: 330–335, 1983.PubMedGoogle Scholar
  7. [7]
    Ginsberg M.D., Busto R.:Rodent models of cerebral ischemia. Stroke, 20: 1627–1642, 1989.PubMedGoogle Scholar
  8. [8]
    Kaplan H., Miezejeski:Development of seizures in the Mongolian gerbil (Meriones unguiculatus). J. Physiol. Psychol., 81: 267–273, 1972.Google Scholar
  9. [9]
    Levine S., Payan H.:Effects of ischemia and other procedure on the brain and retina of the gerbil (Meriones unguiculatus). Exp. Neurol., 16: 255–262, 1966.PubMedGoogle Scholar
  10. [10]
    Levine S., Sohn D.:Cerebral ischemia in infant and adult gerbils: relation to incomplete circle of Willis. Arch. Pathol., 87: 315–317, 1969.PubMedGoogle Scholar
  11. [11]
    Löscher W., Frey H.H.:Evaluation of anticonvulsant drugs in gerbils with reflex epilepsy. Arzneimittelforschung/Drug Res. 34: 1484–1488, 1984.Google Scholar
  12. [12]
    Löscher W.:Influence of pharmacological manipulation of inhibitory and excitatory neurotransmitter system on seizure behavior in the Mongolian gerbil. J. Pharmacol. Exp. Ther., 233: 204–213, 1985.PubMedGoogle Scholar
  13. [13]
    Löscher W., Nolting B., Hönack D.:Evaluation of CPP, a selective NMDA antagonist, in various rodent models of epilepsy. Comparison with other NMDA antagonists, and with diazepam and phenobarbital. Eur. J. Pharmacol., 152: 9–17, 1988.PubMedGoogle Scholar
  14. [14]
    Loskita W.J., Lomax P., Rich S.T.:The gerbils as a model for the study of epilepsy seizure patterns and ontogenesis. Epilepsia, 15: 109–119, 1974.PubMedGoogle Scholar
  15. [15]
    Loskita W.J., Lomax P.:The Mongolian gerbil (Meriones unguiculatus) as a model for the study of the epilepsies: EEG records of seizures. Electroencephalogr. Clin. Neurol., 38: 597–604, 1975.Google Scholar
  16. [16]
    Majkowski J., Kaplan H.:Value of Mongolian gerbils in antiepileptic drug evaluation. Epilepsia, 24: 609–615, 1983.PubMedGoogle Scholar
  17. [17]
    Milne-Edwards A.:Observations sur quelques mammiferes du nord de la Chine. Ann. Sci. Nat. (Zool.), 7: 375–377, 1867.Google Scholar
  18. [18]
    Paul L.A., Fried I., Watanabe K., Forsythe A.B., Scheibel A.B.:Structural correlates of seizure behavior in the Mongolian gerbil. Science, 213: 924–926, 1981.PubMedGoogle Scholar
  19. [19]
    Rich S.T. 1968:The Mongolian gerbil (Meriones Unguiculatus) in research. Laboratory Animal Care, 18: 235–243, 1968.PubMedGoogle Scholar
  20. [20]
    Schonfeld A.R., Glick S.D.:Cerebrovascular abnormalities associated with seizure susceptibility in the Mongolian gerbil. Brain Res., 173: 147–151, 1979.PubMedGoogle Scholar
  21. [21]
    Schonfeld A.R., Glick S.D.:Neuropharmacological analysis of handling-induced seizures in gerbils. Neuropharmacology, 19: 1009–1016, 1980.PubMedGoogle Scholar
  22. [22]
    Thiessen D.D., Lindzey G., Friend H.C.:Spontaneous seizures in the Mongolian gerbil. Psychon. Sci., 11: 227–228, 1968.Google Scholar

Copyright information

© Masson Italia Periodici S.r.l. 1995

Authors and Affiliations

  • Bertorelli R. 
    • 1
  • Adami M. 
    • 1
  • Ongini E. 
    • 1
  1. 1.Research LaboratoriesSchering Plough S.p.A.Comazzo MIItaly

Personalised recommendations