Additivity of protein deficiency and carbon monoxide on placental carboxyhemoglobin in mice.

Abstract

The purpose of the study was to estimate maternal and placental carboxyhemoglobin in protein-deficient and carbon monoxide-exposed mice. Pregnant CD-1 mice were placed on diets containing 27% (control), 16%, 8%, or 4% protein on gestation day 1. The dams were exposed to carbon monoxide concentrations of 0 (control), 65, 125, 250, or 500 ppm from gestation days 8 to 18. The dams were killed on gestation day 18, and blood samples were collected from the maternal hearts and placentas for carboxyhemoglobin determination. Maternal carboxyhemoglobin levels were related to the carbon monoxide exposure levels and were not affected by protein deficiency. Placental carboxyhemoglobin levels were higher than maternal carboxyhemoglobin levels, were related to carbon monoxide exposure levels, and were inversely related to dietary protein levels. The data suggest that maternal protein deficiency enhances the placental carboxyhemoglobin levels resulting from carbon monoxide exposure and exacerbates hypoxic conditions for the developing fetus. Special groups at risk may include drug abusers and cigarette or marijuana smokers.