ISHIDA Yasushi University of Miyazaki, Department of Psychiatry, Professor, 医学部, 教授 (20212897)
AKEDA Ryuichiro University of Miyazaki, Department of Psychiatry, Assistant, 医学部, 助手 (90336298)
ABE Hiroshi University of Miyazaki, Department of Psychiatry, Assistant, 医学部, 助手 (20344848)
NISHIMORI Toshikazu University of Miyazaki, Division of Neurobiology, Professor, 医学部, 教授 (20112211)
we examined the effects of conditioned fear stress(CF) as a stressful manipulation on Fos expression in both monoaminergic, Y-aminobutyric acid(GABA)-ergic and glutamatergic cells in the the prefrontal cortex(PFC), cingulate cortex(Cg), nucleus accumbens(NAC), amygdala(AMY), ventral tegmental area(VTA), substantia nigra(SN) dorsal raphe nucleus(DR), and locus coeruleus(LC). With a double-labeling technique, Fos immunostaining was combined with that for tyrosine hydroxylase(TH), serotonin (5-HT) or GABA for histochemical identification of activated neurons following the stress.
1.Following both the foot shock(FS) and CF stress, the number of Fos-positive cells significantly increased in many regions including the PFC, dorsal DR, and LC whereas did not increase in NAC, AMY, VTA,and SN. In the CF group, Fos-like immunoreactivity was lower in PFC,DR, or LC than corresponding value in the FS group.
2.Sixty percentages of Fos-positive cells in the LC were colocalized with either TH or GABA. Similarly, many of Fos-positive cells in the DR were colocalized with either 5-HT or GABA.
3.Forty-Fifty percentages of Fos-positive cells in the PFC, PVN, DR, LC were colocalized with glutamate N-methyl-D-aspartate(NMDA) receptor subunit 1(NR-1).
4.Following both the FS and CF stress, Protein of the phosphorylated glutamate receptor subunits did not change in the PFC, PVN, SN, DR, LC.
These results indicate that the CF could induce intense Fos expression in the noradrenergic and serotonergic neurons, but not in the dopaminergic neurons, and that GABAergic and glutamatergic neurons in these nuclei are commonly activated by the stress.