Alterations in the offsprings' response to an oral glucose challenge associated with acute maternal malnutrition during late pregnancy

An acutely malnourished pregnant rat model was used to test the effect of intrauterine growth retardation on the subsequent response of the offspring to a loading dose of glucose. Timed-pregnant Harlan-Sprague Dawley rats were given access to only tap water from day 17 through day 19 of their pregnancies (72 hours total). Control mothers had access to lab chow and water throughout their pregnancies. The litters were randomly culled to 4 males and 4 females, whenever possible, and the offspring were given oral glucose tolerance tests at 60, 180 and 360 days of age. At 60 and 180 days of age, malnourished offspring were glucose intolerant (e.g., at 60 days, control males 60 minute serum [glucose] = 9.3 ± 0.1 mM, [malnourished] = 10.1 ± 0.2; [control females] = 9.6 ± 0.2 versus [malnourished] = 10.5 ± 0.3; (overall p < 0.05 for treatment). Plasma insulin levels for the malnourished offspring in response to the glucose load were not significantly different at 0 and 30 minutes after the glucose dose. However, at 60 and 120 minutes after the dose, serum insulin levels were significant lower in the malnourished animals ([control males] = 478 ± 47 pMoles/liter versus 351 ± 34; [control females] = 436 ± 54 versus 300 ± 33; p < 0.05 for treatment). Thus, the insulin to glucose ratio (pMoles/mM) were markedly decreased at the latter time points (control male ratio = 49 ± 3, malnourished = 34 ± 3; control female = 44 ± 4 versus 29 ± 1; p < 0.05 for treatment). At 360 days of age, both male and female malnourished offspring had blood glucose levels comparable to controls in response to the oral glucose challenge. However, while the insulin levels of the malnourished males were comparable to control values, malnourished female insulin levels were lower at all time points.