Reactivity of astrocytes in hippocampal CA1 area in rats after administration of habanero peppers.

Introduction: Astrocytes react to microenvironmental changes. Their reactivity is manifested by an increase in glial fibrillary acidic protein (GFAP) and S100b protein levels, hypertrophy and hyperplasia. The aim of the study was to analyse immunoreactive GFAP (GFAP-IR) and S100b (S100b-IR) astrocytes of hippocampal CA1 area in adult rats intragastrically (i.g.) treated with habanero peppers.

Material and methods: Brains from 10 control rats (group C) and 10 rats receiving oil suspension of habanero fruits for 7 days (group I-7) or 28 days (group II-28) were used. Antibodies against GFAP and S100b were used for immunohistochemistry. Morphology and distribution of astrocytes was evaluated under light microscope and their density was quantitatively analysed.

Results: In the CA1 hippocampal area of group II-28 rats, GFAP-IR cells with numerous, branched processes were observed. S100b-IR astrocytes had delicate, single processes in comparison with cells without processes observed in groups I-7 and C. In groups I-7 and II-28, GFAP-IR astrocytes' density significantly increased in SR - stratum radiatum of hippocampal CA1 area. In group I-7, a density of cells with the expression of S100b was significantly increased in SO - stratum oriens layer. In group II-28, the density of S100b-IR astrocytes was decreased.

Conclusions: Habanero peppers administrated to rats, especially for a longer time, caused reactive changes in the astrocytes in hippocampal CA1 area, and thus these glial cells may protect neurons against excitotoxic damage.