Persistent neocortical astrogliosis in adult wistar rats following prenatal ethanol exposure.
Timed pregnant wistar rats were divided randomly into groups A and B (n=6) each and C (n=4). Group A received a daily ethanol dose of 5.8 g/kg body weight per day, at 16.00 h on days 9-12th of gestation by intragastric intubations. Group B was pair-fed along with the treated rats and received an isocaloric solution of sucrose to substitute for the ethanol in the experimental group, for the same duration, while group C received standard chow and water ad libitum. The adult offsprings at 42 days of age, (n=10) from each group were sacrificed by whole body perfusion-fixation, after anaesthesia by an overdose of pentothal intraperitoneally. Specimens of neocortical samples were processed routinely for paraffin embedding and sections of 6 microm thickness stained for neurohistology. Another set of specimens was cryosectioned at -23 degrees C after cryoprotection in 30% sucrose/PBS and evaluated for GFAP immunohistochemistry. The study showed a distortion of the microanatomy of the neocortex in the treatment group A, particularly of layer V pyramidal neurons, which revealed mostly pyknotic pyramidal neurons with broken dendrites, collapsed cell bodies, obliterated nuclei and nucleoli. No differences were found between the brains from rats in groups B and C. There were widespread focal areas of reactive astrogliosis, more prominent within the layer V. Astrocytes demonstrated highly stained GFAP-positive immunoreactivity with heavy fibrillary processes in the neocortex of group A offsprings compared to the controls. The sub-pial regions were, however, sparse. In conclusion, this study confirms the hypothesis that microanatomical and microchemical changes following prenatal ethanol exposure persist into adulthood in rats.
Fakoya
Francis Adelade
FA
Department of Anatomy and Cell Biology, Faculty of Basic Medical Sciences, Obafemi Awolowo University, P.O. Box 1995, Ile-Ife 220005, Nigeria. ffakoya@oauife.edu.ng
D000818:Animals; D001253:Astrocytes / Q000473:pathology*; D000431:Ethanol / Q000633:toxicity*; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D019579:Neocortex / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology*; D009474:Neurons / Q000187:drug effects / Q000473:pathology; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D017208:Rats, Wistar
D005904:Glial Fibrillary Acidic Protein; D000431:Ethanol