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Benzodiazepine anti-conflict effects in maudsley reactive (MR/Har) and non-reactive (MNRA/Har) rats

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Abstract

The Maudsley Reactive (MR/Har) and Non-Reactive (MNRA/Har) rat strains, bred originally by Broadhurst for differences in Open Field Defecation, also differ in their control (i.e., non-drug) behavior in the Conditioned Suppression of Drinking (CSD) conflict procedure, a second “model” behavior for the study of anxiety and/or emotionality in rats. The present studies compared the effects of diazepam and alprazolam on CSD behavior in these two strains of rats. In daily 10-min sessions, water-deprived rats were trained to drink from a tube that was occasionally electrified (0.2–0.5 mA), electrification being signaled by a tone. Both diazepam and alprazolam increased punished responding in a dose-related manner. The per cent increase in punished responding (for diazepam only) was comparable in the two strains; however, both statistical and empirical approaches indicated that the magnitude of the anti-conflict effect of benzodiazepines in MNRA/Har versus MR/Har rats was not related to differences in baseline (i.e., non-drug) punished responding. Based on the absolute change in shocks received, rats of the MNRA/Har strain exhibited a significantly greater anti-conflict effect following diazepam or alprazolam treatment than did rats of the MR/Har strain. These findings further the hypothesis that the behavioral differences exhibited by Maudsley MR/Har and MNRA/Har rat strains may constitute a genetically-based “animal model” for the study of emotionality and/or anxiety.

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References

  • Blizard DA (1981) The Maudsley reactive and nonreactive strains: A North American perspective. Behav Genet 11:469–489

    Google Scholar 

  • Blizard DA, Liang B (1979) Plasma catecholamines under basal and stressful conditions in rat strains selectively bred for differences in response to stress. In: Usdin E, Kopin IJ, Barchas J (eds) Catecholamines: basic and clinical frontiers. Pergamon Press, New York

    Google Scholar 

  • Blizard DA, Altman HJ, Freedman LS (1982) The peripheral sympathetic nervous system in rat strains bred selectively for differences in response to stress. Behav Neural Biol 34:319–325

    Google Scholar 

  • Broadhurst PL (1960) Experiments in psychogenetics. In: Eysenck HJ (ed) Experiments in personality, psychogenetics and psychopharmacology. Routledge and Kegan Paul, London

    Google Scholar 

  • Broadhurst PL (1962) A note on further progress in a psychogenetic experiment. Psychol Rep 1065–1066

  • Broadhurst PL (1975) The Maudsley reactive and nonreactive strains of rats: A survey. Behav Genet 5:299–319

    Google Scholar 

  • Commissaris RL, Harrington GH, Ortiz AM, Altman HJ (1986) Maudsley reactive and non-reactive rats strains: Differential performance in a conflict task. Physiol Behav 38:291–294

    Google Scholar 

  • Commissaris RL, Vasas RJ, McCloskey TC (1988) Convulsant versus typical barbiturates: effects on conflict behavior in the rat. Pharmacol Biochem Behav 29:631–634

    Google Scholar 

  • Commissaris RL, McCloskey TC, Harrington GM, Altman HJ (1989) MR/Har and MNRA/Har Maudsley rat strains: Differential response to chlordiazepoxide in a conflict task. Pharmacol Biochem Behav 32:801–805

    Google Scholar 

  • Eysenck HJ, Broadhurst PL (1964) Experiments with animals: Introduction. In: Eysenck HJ (ed) Experiments in motivation. Pergamon Press, New York

    Google Scholar 

  • Ford RD, Rech RH, Commissaris RL, Mayer L (1979) Effects of acute and chronic interactions of diazepam andd-amphetamine on punished and unpunished behavior of rats. Psychopharmacology 65:197–204

    Google Scholar 

  • Geller I (1964) Relative potencies of benzodiazepines as measured by their effects on conflict behavior. Arch Int Pharmacodyn Ther 149:243–247

    Google Scholar 

  • Geller I, Seifter J (1960) The effects of meprobamate, barbiturates,d-amphetamine and promazine on experimentally induced conflict in the rat. Psychopharmacology 1:482–492

    Google Scholar 

  • Geller I, Kulak JT, Seifter J (1962) Attenuation of chlordiazepoxide and chlorpromazine on a punished discrimination. Psychopharmacology 3:374–385

    Google Scholar 

  • Harrington GM (1981) The Har strains of rats: origin and characteristics. Behav Genet 11:445–468

    Google Scholar 

  • Harrington GH, Blizard DA (1983) Open-field behavior in the Maudsley reactive and nonreactive strains: procedural variations. Behav Genet 13:91–94

    Google Scholar 

  • Kilts CD, Commissaris RL, Rech RH (1981) Comparison of anti-conflict drug effects in three experimental models of anxiety. Psychopharmacology 74:290–296

    Google Scholar 

  • Liang B, Blizard DA (1978) Central and peripheral norepinephrine concentrations in rat strains selectively bred for differences in response to stress. Pharmacol Biochem Behav 8:75–80

    Google Scholar 

  • Marangos PJ, Insel TR, Montgomery P, Tamborska E (1987) Brain adenosine receptors in Maudsley Reactive and Non-Reactive rats. Brain Res 421:69–74

    Google Scholar 

  • McCloskey TC, Paul BK, Commissaris RL (1987) Buspirone effects in an animal conflict procedure: Comparison with diazepam and phenobarbital. Pharmacol Biochem Behav 27:171–175

    Google Scholar 

  • McCloskey TC, Damian GM, Brown BD, Barraco RA, Altman HJ, Commissaris RL (1988) Antagonism of the anti-conflict effects of phenobarbital, but not diazepam, by the A-1 adenosine agonistl-PIA. Neurosci Abstr 14:1261

    Google Scholar 

  • Robertson HA, Martin IL, Candy JM (1978) Differences in benzodiazepine receptor binding in Maudsely Reactive and Maudsley Non-Reactive rats. Eur J Pharmacol 50:455–457

    Google Scholar 

  • Slater J, Blizard DA, Pohorecky LA (1977) Central and peripheral norepinephrine metabolism in rat strains selectively bred for differences in response to stress. Pharmacol Biochem Behav 6:511–520

    Google Scholar 

  • Steele RGD, Torrie JH (1985) Principles and procedures of statistics. McGraw-Hill, New York

    Google Scholar 

  • Sudak HS, Maas JW (1964) Neurochemical correlations in Reactive and Non-Reactive strains of rats. Science 46:418–420

    Google Scholar 

  • Tamborska E, Insel T, Marangos P (1986) ‘Peripheral’ and ‘central’ type benzodiazepine receptors in Maudsley rats. Eur J Pharmacol 126:281–287

    Google Scholar 

  • Vogel JR, Beer B, Clody DE (1971) A simple and reliable conflict procedure for testing antianxiety agents. Psychopharmacologia 21:1–7

    Google Scholar 

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Commissaris, R.L., Harrington, G.M. & Altman, H.J. Benzodiazepine anti-conflict effects in maudsley reactive (MR/Har) and non-reactive (MNRA/Har) rats. Psychopharmacology 100, 287–292 (1990). https://doi.org/10.1007/BF02244595

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  • DOI: https://doi.org/10.1007/BF02244595

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