Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

125I-iomazenil-benzodiazepine receptor binding during psychological stress in rats

  • 35 Accesses

  • 3 Citations


Objective: We investigated the changes in125I-iomazenil (125I-IMZ) benzodiazepine receptor (BZR) binding with psychological stress in a rat model.Methods: Six male Wistar rats were placed under psychological stress for 1 hour by using a communication box. No physical stress was not received. 1.85 MBq of125I-IMZ was injected into the lateral tail vein and the rat was killed 3 hours later. Twenty-micrometer-thick sections of the brain were collected and % injected dose per body weight (%ID/BW) of eleven regions (frontal, parietal, temporal, occipital cortices, caudate putamen, accumubens nuclei, globus pallidus, amygdala, thalamus, hippocampus and hypothalamus) were calculated by autoradiography. The %ID/BW of rats which were placed under psychological stress was compared with that of 6 control rats.Results: The %ID/BW of rats which were placed under psychological stress diffusely tended to show a reduction in125I-IMZ-BZR binding. A significant decrease in BZR binding was observed in the hippocampus of the rats which were placed under psychological stress.Conclusion:125I-IMZ-BZR binding tended to decrease throughout the brain.

This is a preview of subscription content, log in to check access.


  1. 1.

    Beer HF, Blauenstein PA, Hasler PH, Delaloye B, Riccabona G, Bangerl I, et al.In vitro andin vivo evaluation of iodine-123-Ro 16-0154: a new imaging agent for SPECT investigations of benzodiazepine receptors.J Nucl Med 1990; 31: 1007–1014.

  2. 2.

    Holl K, Deisenhammer E, Dauth J, Carmann H, Schubiger PA. Imaging benzodiazepine receptors in the human brain by single photon emission computed tomography (SPECT).Nucl Med Biol 1989; 16: 759–763.

  3. 3.

    Uchiyama M, Sue H, Fukumitsu N, Mori Y, Kawakami K. Assessment of cerebral benzodiazepin receptor distribution in anxiety disorders by123I-iomazenil-SPECT: comparison to cerebral perfusion scintigraphy by123I-IMP.NIPPON ACTA RADIOLOGICA 1997; 57: 41–46.

  4. 4.

    Nakabeppu Y, Nakajo M, Naruo T, Obo Y, Nozoe S, Takigawa M, et al. I-123 iomazenil SPECT in patients with mental disorders.Ann Nucl Med 1997; 11: 339–344.

  5. 5.

    Tokunaga M, Ida I, Higuchi T, Mikuni M. Alterations of benzodiazepine receptor binding potential in anxiety and somatoform disorders measured by123I-iomazenil SPECT.Radiation Medicine 1997; 15: 163–169.

  6. 6.

    Takahashi M, Odano I, Fujita S, Ohkubo M,125I-iomazenil binding shows stress- and/or diazepam-induced reductions in mouse brain: supporting data for123I-iomazenil SPECT study of anxiety disorders.Ann Nucl Med 1997; 11: 243–250.

  7. 7.

    Torizuka K, Uemura K, Toru M, Shinohara Y, Nishimura T, Yonekura Y, et al. A phase 3 clinical trial of123I-iomazenil, a new central-type benzodiazepine receptor imaging agent (part 2)—report on clinical usefulness in diagnosis of degenerative neurological diseases and mental disorders—.KAKU IGAKU (Jpn J Nucl Med) 1996; 33: 303–318.

  8. 8.

    Weizman R, Weizman A, Kook KA, Vocci F, Deutsch SI, Paul SM. Repeated swim stress alters brain benzodiazepine receptors measuredin vivo.J Pharmacol Exp Ther 1989; 249: 701–707.

  9. 9.

    Kaneko K, Kurumaji A, Shibuya H, Nabeshima T, Toru M. The effects of single and repeated phencyclidine administration on [125I] iomazenil binding in the rat brain.Nerochem 1996; 29: 279–287.

  10. 10.

    Northoff G, Steinke R, Czcervenka C, Krause R, Ulrich S, Danos P, et al. Decreased density of GABA-A receptors in the left sensorimotor cortex in akinetic catatonia: investigation ofin vivo benzodiazepine receptor binding.J Neural Neurosurg Psychiatry 1999; 67: 445–450.

  11. 11.

    Ishikawa M, Hara C, Ohdo S, Ogawa N. Plasama corticosterone response of rats with sociopsychological stress in the communication box.Physiol Behav 1992; 52: 475–480.

  12. 12.

    Ogawa N, Kuwahara K. Psychophysiology of emotion-communication of emotion.Jpn J Psychosom Med 1966; 6: 352–357.

  13. 13.

    Hommer DW, Skolnick P, Paul SM. The benzodiazepine/ GABA receptor complex and anxiety. InPsychopharmacology, 3rd eds (Meltzer HY ed; Raven Press, New York), 1987: 977–983.

  14. 14.

    Moehler H, Okada R. Benzodiazepine receptor: demonstration in the central nervous system.Science 1977; 198: 849–851.

  15. 15.

    Nomura N, Maeda N, Kuratani K, Yamaguchi I. Sulpiride specifically attenuates psychological stress-induced gastric lesions in rodents.Jpn J Pharmacol 1995; 68: 33–39.

  16. 16.

    Hotta M, Shibasaki T, Arai K, Demura H. Corticotropin-releasing factor receptor type 1 mediates emotional stress-induced inhibition of food intake and behavioral changes in rats.Brain Res 1999; 823: 221–225.

  17. 17.

    Musty RE, Jordan MP, Lenox RH. Criterion for learned helplessness in the rat: a redefinition.Pharmacol Biochem Behav 1990; 36: 739–744.

  18. 18.

    Nomura K, Maeda N, Yoshino T, Yamaguchi I. A mechanism of 5-HT3 receptor mediation is involved etiologically in the psychological stress lesion in the stomach of the mouse.J Pharmacol Exp Ther 1994; 271: 100–106.

  19. 19.

    Zhukov DA, Vinogradova EP. Agonistic behavior during stress prevents the development of learned helplessness in rats.Neuroscience and Behavioral Physiology 1998; 2: 206–210.

  20. 20.

    Ishikawa M, Ohdo S, Watanabe H, Hara C, Ogawa N. Alteration in circadian rhythm of plasma corticosterone in rats following sociopsychological stress induced by communication box.Physiol Behav 1995; 57: 41–47.

  21. 21.

    Sato Y, Suzuki N, Horita H, Wada H, Shibuya A, Adachi H, et al. Effects of long-term psychological stress on sexual behavior and brain catecholamine levels.J Androl 1996; 17: 83–90.

  22. 22.

    Biggio G, Concas A, Serra M, Salis M, Corda MG, Nurchi V, et al. Stress and β-carbolines decrease the density of low affinity GABA binding sites; an effect reversed by diazepam.Brain Res 1984; 305: 13–18.

Download references

Author information

Correspondence to Nobuyoshi Fukumitsu.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Fukumitsu, N., Tsuchida, D., Ogi, S. et al. 125I-iomazenil-benzodiazepine receptor binding during psychological stress in rats. Ann Nucl Med 16, 231–235 (2002). https://doi.org/10.1007/BF02996307

Download citation

Key words

  • 125I-iomazenil
  • benzodiazepine receptor
  • psychological stress
  • rat
  • communication box