Effect of diabetes mellitus on rat placenta cellularity.

Transcellular placental maternofetal flux of calcium and magnesium is reduced in diabetic pregnancy in the rat which might be due to changes in placental cellularity. In order to investigate this wet and dry weight, DNA and protein content were measured in placentas from untreated diabetic (D(O)), insulin-treated diabetic (D(I)) and control rats (C) on day 21 of gestation (term=23 days). Wet and dry weights (mg; mean+/-S.E.M.) were 418+/-13, 474+/-19, 416+/-14 and 66+/-3, 75+/-3, 67+/-3 in C, D(O) and D(I) groups, respectively. Total DNA and protein content (mg) was 1.8+/-0.2, 1.7+/-0.1, 1.5+/-0.1 and 50.4+/-2.4, 54.9+/-2.6, 51.9+/-3.3 in C, D(O) and D(I) groups, respectively. The data suggest that placental cellularity is unaffected by maternal diabetes mellitus in the rat and is unlikely to directly affect maternofetal flux of calcium and magnesium.