DEVELOPING RAT PURKINJE-CELLS ARE MORE VULNERABLE TO ALCOHOL-INDUCED DEPLETION DURING DIFFERENTIATION THAN DURING NEUROGENESIS

This study compared the extent of cerebellar Purkinje cell depletion i nduced by administering alcohol to rats during two temporally distinct periods of Purkinje cell development-neurogenesis and early different iation. One group received alcohol (5 g/kg/day) during and shortly aft er Purkinje cell neurogenesis (gestational days 13-18) via oral intuba tion of pregnant dams. A second group received alcohol(2.5 g/kg/day) d uring early Purkinje cell differentiation (postnatal days 4-9) via art ificial rearing of pups. The two alcohol treatment protocols were desi gned to match the cyclic daily blood alcohol profiles of the two group s as closely as possible. Pair-fed intubated controls, artificially re ared gastrostomy controls, and normally reared ad lib/suckle controls were also evaluated. Mean peak blood alcohol concentrations (BACs) wer e 266 mg/dl for the intubated pregnant darns and 205 mg/dl for the pup s exposed postnatally. Purkinje cell profiles were counted from single , 2-mu m-thick midsaggital sections on postnatal day 10. Alcohol expos ure during neurogenesis resulted in no significant change in Purkinje cell profile densities. Exposure during differentiation produced signi ficant reductions in Purkinje cell profile densities, predominantly in the early maturing regions of the vermis (lobules I-IV and IX-X). The se results indicate that Purkinje cells are more vulnerable to alcohol -induced population depletion during differentiation than during neuro genesis.