The effect of magnesium depletion on thyroid function in rats

Journal Article · Wed Aug 01 04:00:00 EDT 1984 · J. Nutr.; (United States)

OSTI ID:6590974

Hsu, J M; Root, A W; Duckett, G E; Smith, Jr, J C; Yunice, A A; Kepford, G

The effects of dietary magnesium (Mg) depletion on thyroid function were studied in young male rats. The rats were fed a semipurified diet containing either 12 ppm Mg (deficient rats) or 662 ppm Mg (control rats) for 14 to 28 days. Results showed that the Mg-deficient rats had decreased body weight gain, lowered concentrations of plasma thyroxine (T4) and Mg, but increased weight of the thyroid gland when expressed in proportion to the body weight (milligrams/100 g). There was no difference in the accumulation (uptake) of 131I, 24 hours after Na131I injection, between the Mg-deficient and Mg-supplemented rats. The protein-bound 131I (PB131I) level and the ratio of PB131I to total 131I in plasma was significantly reduced in Mg-deficient rats. Serum thyroid-stimulating hormone (TSH) levels after thyrotropin-releasing hormone injection (TRH, 50 ng/100 g body weight) increased fivefold at 30 minutes, but declined to near the basal level at 2 hours in both groups. No consistent difference in TSH response was observed between the two treatments. Serum T4 response to TRH challenge was significantly reduced in Mg-deficient as compared to Mg-adequate rats at all time intervals. The reduction of T4 level could be due to an impaired T4 synthesis or release in Mg-deficient rats.

• Research Organization: Veterans Administration Medical Center, Bay Pines, FL
• OSTI ID: 6590974
• Journal Information: J. Nutr.; (United States), Journal Name: J. Nutr.; (United States) Vol. 114:8; ISSN JONUA
• Country of Publication: United States
• Language: English

Related Subjects

551001* -- Physiological Systems-- Tracer Techniques
560305 -- Chemicals Metabolism & Toxicology-- Vertebrates-- (-1987)
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKALINE EARTH METALS
AMINO ACIDS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BODY
CARBOXYLIC ACIDS
CPB
DAYS LIVING RADIOISOTOPES
DIET
ELEMENTS
ENDOCRINE GLANDS
GLANDS
HORMONES
INTERMEDIATE MASS NUCLEI
IODINE 131
IODINE ISOTOPES
ISOTOPES
MAGNESIUM
MAMMALS
METALS
NUCLEI
NUTRITIONAL DEFICIENCY
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
ORGANS
PBI
PEPTIDE HORMONES
PHYSIOLOGY
PITUITARY HORMONES
PROTEINS
RADIOISOTOPES
RATS
RODENTS
THYROID
THYROID HORMONES
THYROXINE
TRH
TSH
UPTAKE
VERTEBRATES