Effects of Experimentally Induced Gestational Diabetes on Fetomaternal Parameters, Exploratory Behavior and Emotional Reactivity in Rat Offspring

Gestational diabetes mellitus adversely affects maternal health, fetal development, and long-term neurobehavioral outcomes. This study evaluated the impact of experimentally induced gestational diabetes on fetomaternal parameters, exploratory behavior, and emotional reactivity in rat offspring. Pregnant Wistar rats were treated on gestational day 6 with alloxan at 100 mg/kg, 120 mg/kg, or vehicle (control). Blood glucose levels were measured 72 h post-injection. Behavioral assessments were performed in 9 offspring from partially diabetic dams (from 4 litters) and 9 offspring from control dams (selected from 6 control litters) on postnatal days 10, 15, 20, 25, and 30 using a hole-board test. Alloxan injection successfully induced dose-dependent metabolic disturbances. Blood glucose levels were significantly higher in diabetic (, ) and partially diabetic rats (, ) compared to control animals (). While no maternal deaths occurred in the 100 mg/kg group, all severely diabetic dams in the 120 mg/kg group died during gestation. Moderate hyperglycemia in PDR dams permitted full-term pregnancy but resulted in increased postnatal offspring mortality ( deaths out of pups) and morphological abnormalities, specifically tail shortening. Neurobehaviorally, exploratory activity demonstrated a non-linear developmental trajectory, peaking at PND 20 and declining thereafter, without significant differences between control and PDR offspring. Emotional defecation differed significantly at PND 15 (); however, this isolated finding should be interpreted cautiously because the overall treatment effect was not significant. In conclusion, maternal hyperglycemia severely compromises fetal viability and morphological development, whereas no clear evidence of persistent alterations in exploratory activity or emotional reactivity was observed following moderate prenatal hyperglycemia.