[Changes in absorption of manganese during gravidity and lactation]

Model studies were conducted using isolated everted sacs of small intestines of rats to test the absorption of manganese during pregnancy and lactation. The intestinal transfer of manganese to the serosal solution and the uptake of manganese into the intestinal wall were measured. The results agree well and yield a comparable pattern of absorption. The Mn absorption rises only slightly in the first and second third of gestation (6th and 12th days of gestation). In the third part of pregnancy (18th day), however, three times more manganese is absorbed compared to the nonpregnant, nonlactating control animals (p less than 0.001). The Mn transfer and uptake decrease distinctly at the day of birth (20th day of gestation and 1st day of lactation) but only for this short period. The absorption increases again significantly (p less than 0.05) on the 3rd, 5th and 8th days of lactation, respectively, while it decreases at the end of lactation (21st day of lactation) to the level of the controls. Reasons for this pattern are discussed.