Differential Effect of Caffeine Consumption on Diverse Brain Areas of Pregnant Rats.
BACKGROUND
It has previously been shown that during gestation, the mother's brain has an increase in glial fibrillary acidic protein (GFAP)-immunoreactivity (-ir) and a decrease in the mRNA level of A1 adenosine receptor. Little is known about the A2A adenosine receptor in the maternal brain, and whether caffeine consumption throughout gestational period modifies GFAP and adenosine receptor density in specific brain areas. This study was undertaken to investigate the protein density of GFAP and adenosine receptors (A1 and A2A subtypes) in different regions of pregnant rat brain and the possible effect of caffeine on these proteins.


METHODS
For this purpose, we examined the GFAP-, A1- and A2A-ir in the cingulate cortex (Cg2), dentate gyrus (DG), medial preoptic area (mPOA), secondary somatosensory cortex (S2), and striatum (Str) of pregnant Wistar rats (drug-free tap water or water with 1g/L diluted caffeine).


RESULTS
We show a consistent and highly significant reduction of GFAP-ir in caffeine-treated pregnant rats in most of the areas analyzed. Our data demonstrate that caffeine consumption induces a significant increase of A2A-ir in Str. Concerning A1 receptor, the observed changes are dependent on the region analyzed; this receptor density is increased in Cg2, DG, and mPOA and decreased in the somatosensory cortex and Str. The results were confirmed by Western blotting.


CONCLUSIONS
Our results suggest that chronic caffeine exposure could modify the physiolological situation of gestation by a reorganization of the neural circuits and the adenosine neuromodulator system.
Department of Inorganic and Organic Chemistry and Biochemistry, Faculty of Medicine, Regional Center of Biomedical Research, University of Castilla-La Mancha , Ciudad Real, Spain . ; Department of Inorganic and Organic Chemistry and Biochemistry, Chemistry Faculty, Regional Center of Biomedical Research, University of Castilla-La Mancha , Ciudad Real, Spain .
Inmaculada
I
Ballesteros-Yáñez
Department of Inorganic and Organic Chemistry and Biochemistry, Chemistry Faculty, Regional Center of Biomedical Research, University of Castilla-La Mancha , Ciudad Real, Spain . ; Department of Nursing, Faculty of Nursing, Occupational and Speech Therapies, University of Castilla-La Mancha , Talavera de la Reina, Spain .
Carlos Alberto
CA
Castillo
Department of Mathematics, Faculty of Medicine, University of Castilla-La Mancha , Ciudad Real, Spain .
Mariano
M
Amo-Salas
Department of Inorganic and Organic Chemistry and Biochemistry, Faculty of Medicine, Regional Center of Biomedical Research, University of Castilla-La Mancha , Ciudad Real, Spain . ; Department of Inorganic and Organic Chemistry and Biochemistry, Chemistry Faculty, Regional Center of Biomedical Research, University of Castilla-La Mancha , Ciudad Real, Spain .
José Luis
JL
Albasanz
Department of Inorganic and Organic Chemistry and Biochemistry, Faculty of Medicine, Regional Center of Biomedical Research, University of Castilla-La Mancha , Ciudad Real, Spain . ; Department of Inorganic and Organic Chemistry and Biochemistry, Chemistry Faculty, Regional Center of Biomedical Research, University of Castilla-La Mancha , Ciudad Real, Spain .
Mairena
M
Martín