DEPLETION OF INDIVIDUALS WITH OUTSTANDINGLY HIGH CEREBRAL DEVELOPMENT IN RATS SUBJECTED TO PRENATAL UNDERNUTRITION

In previous reports we have identified individual rats whose neonatal cerebral parameters (weight, DNA, protein) were "outstandingly high" (OH) (defined throughout as being more than 1 standard deviation (OH1) or 2 standard deviations (OH2) above the mean of normal population). In the present work we have established that pregnant rats subjected to chronic undernutrition (2/3 of ad lib diet) produce offspring in which occurrence of OH individuals is significantly depleted: OH1 control 7 to 16%, undernourished 0.5 to 2.1%; OH2 control 0.7 to 1.2%, undernourished 0.0%. Thus, the harmful effects of chronic undernutrition are twofold: 1) Significant reduction ofmean values of cerebral parameters in the population as a whole, and 2)Depletion of occurrence of cerebral OH individuals. If these parameters are correlated with behavioral performance, the depletion of individuals with outstandingly high cerebral parameters (2) maybe even more harmful than the well known reduction of mean values of these parameters in the population as a whole (1).