1,25(OH) sub 2 D sub 3 and Ca-binding protein in fetal rats: Relationship to the maternal vitamin D status

Journal Article · Fri Apr 01 04:00:00 EST 1988 · American Journal of Physiology; (USA)

OSTI ID:6727450

Verhaeghe, J; Thomasset, M; Brehier, A; Van Assche, F A; Bouillon, R ^[1]

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1. Katholieke Universiteit Leuven (Belgium) Institut National de la Sante et de la Recherche Medical (France)

The autonomy and functional role of fetal 1,25-dihydroxyvitamin D{sub 3} (1,25(OH){sub 2}D{sub 3}) were investigated in nondiabetic and diabetic BB rats fed diets containing 0.85% calcium-0.7% phosphorus or 0.2% calcium and phosphorus and in semistarved rats on the low calcium-phosphorus diet. The changes in maternal and fetal plasma 1,25(OH){sub 2}D{sub 3} were similar: the levels were increased by calcium-phosphorus restriction and decreased by diabetes and semistarvation. Maternal and fetal 1,25(OH){sub 2}D{sub 3} levels were correlated. The vitamin D-dependent calcium-binding proteins (CaBP{sub 9K} and CaBP{sub 28K}) were measured in multiple maternal and fetal tissues and in the placenta of nondiabetic, diabetic, and calcium-phosphorus-restricted rats. The distributions of CaBP{sub 9K} and CaBP{sub 28K} in the pregnant rat were similar to that of the growing rat. The increased maternal plasma 1,25(OH){sub 2}D{sub 3} levels in calcium-phosphorus-restricted rats were associated with higher duodenal CaBP{sub 9K} and renal CaBPs, but placental CaBP{sub 9K} was not different. In diabetic pregnant rats, duodenal CaBP{sub 9K} was not different. In diabetic pregnant rats, duodenal CaBP{sub 9K} tended to be lower, while renal CaBPs were normal; placental CaBP{sub 9K} was decreased. The results indicate that in the rat fetal 1,25(OH){sub 2}D{sub 3} depends on maternal 1,25(OH){sub 2}D{sub 3} or on factors regulating maternal 1,25(OH){sub 2}D{sub 3}. The lack of changes in fetal CaBP in the presence of altered fetal plasma 1,25(OH){sub 2}D{sub 3} levels confirms earlier data showing that 1,25(H){sub 2}D{sub 3} has a limited hormonal function during perinatal development in the rat.

• OSTI ID: 6727450
• Journal Information: American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 254:4; ISSN 0002-9513; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALINE EARTH METAL COMPOUNDS
ANIMALS
BIOASSAY
CALCIUM COMPOUNDS
CHOLECALCIFEROL
DIABETES MELLITUS
DIAGNOSTIC TECHNIQUES
DIET
DISEASES
DISTRIBUTION
ENDOCRINE DISEASES
FASTING
FEMALES
FETAL MEMBRANES
FETUSES
HORMONES
HYDROGEN COMPOUNDS
IMMUNOASSAY
IMMUNOLOGY
INSULIN
ISOTOPE APPLICATIONS
MAMMALS
MEMBRANES
METABOLIC DISEASES
NUTRITIONAL DEFICIENCY
ORGANIC COMPOUNDS
PEPTIDE HORMONES
PHOSPHORUS COMPOUNDS
PLACENTA
PREGNANCY
PROTEINS
RADIOASSAY
RADIOIMMUNOASSAY
RADIOIMMUNODETECTION
RADIOIMMUNOLOGY
RATS
RODENTS
TISSUE DISTRIBUTION
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES
VITAMIN D
VITAMINS