The previous research in this program, particularly that conducted during the preceding grant period, has demonstrated that sexually dimorphic behaviors and CNS structures are incompletely masculinized in adult male rats stressed during fetal development. The etiology of this syndrome involves abnormal ontogenetic plasma testosterone secretion and testicular steroidogenesis in stressed fetuses. Similar testicular hormone alterations have been reported in fetuses of mothers ingesting alcohol during pregnancy. Furthermore, exposure to stress increases alcohol intake. No data exist regarding cumulative or interactive effects of maternal stress and alcohol exposure during gestation on the sexual differentiation of males. This proposal addresses this problem through four projects. Project 1 entails the production of a set of male offspring from dams exposed to alcohol and/or stress during pregnancy. The method of choice for alcohol exposure will be one commonly used in alcohol research in which the sole access to food and water consists of a nutritionally balanced liquid diet in which 36% of the calories are derived from ethanol. The diet administered to control animals is isocalorically equivalent but ethanol is replaced with maltose-dextrin or sucrose. The stress and control groups of animals will be subdivided into four different dietary treatments that are given from day 10-21 of gestation. Stress and control mothers in one dietary condition will receive access to the liquid alcohol diet. In a second dietary condition, stress females will receive access to the liquid control diet, while control animals will have an amount of liquid diet available that will be yoked to that consumed by the stressed animals. The third and fourth dietary treatments will serve as dietary controls involving equal caloric intake for the alcohol treatment groups. Because rats decrease their food intake when alcohol is introduced into their diet the control groups are needed to dissociate the effects of ethanol from those of undernutrition. The treatment groups produced by this 2 X 4 factorial design allow comparisons for the stress plus ethanol, stress alone, and ethanol alone groups with equi-caloric consuming, untreated groups. The design also provides for evaluation of the cumulative effects of stress plus ethanol in comparison to stress alone animals whose dietary intake is yoked to that of stress plus ethanol mothers. Blood levels of alcohol will be determined independently in a separate set of females that are bred and placed on the liquid ethanol diet or liquid control diet. Half of the animals on the ethanol diet will be stressed and blood will be sampled from all animals on the eighteenth day of gestation. On the day of birth, pups from litters in the various treatment conditions will be counted, sexed, weighed, and ano-genital distance measured. Litters will be cross-fostered to untreated females that had given birth within the preceding 48 hours.
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