Effect of iodide on glucose oxidation and /sup 32/P incorporation into phospholipids stimulated by different agents in dog thyroid slices

Journal Article · Wed Mar 01 04:00:00 EST 1989 · Endocrinology; (United States)

OSTI ID:6170940

Tseng, F Y; Rani, C S; Field, J B

Since iodide (I-) inhibits TSH stimulation of cAMP formation, which mediates most of the effects of the hormone, it has been assumed that this accounts for the inhibitory action of iodide on the thyroid. However, TSH stimulation of 32P incorporation into phospholipids and stimulation of thyroid metabolism by other agonists, such as carbachol, phorbol esters, and ionophore A23187, is not cAMP mediated. The present studies examined the effect of iodide on stimulation of glucose oxidation and 32P incorporation into phospholipids by TSH and other agonists to determine if the inhibition of cAMP formation was responsible for the action of iodide. Preincubation of dog thyroid slices for 1 h with iodide (10(-4) M) inhibited TSH-, (Bu)2cAMP-, carbachol-, methylene blue-, 12-O-tetradecanoyl phorbol-13-acetate-, ionophore A23187-, prostaglandin E1-, and cholera toxin-stimulated glucose oxidation. I- also inhibited the stimulation by TSH, 12-O-tetradecanoyl phorbol-13-acetate, carbachol, and ionophore A23187 of 32P incorporation into phospholipids. The inhibition was similar whether iodide was added 2 h before or simultaneously with the agonist. I- itself sometimes stimulated basal glucose oxidation, but had no effect on basal 32P incorporation into phospholipids. The effects of iodide on basal and agonist-stimulated thyroid metabolism were blocked by methimazole (10(-3) M). When dog thyroid slices were preloaded with 32PO4 or (1-14C)glucose, the iodide inhibition of agonist stimulation disappeared, suggesting that the effect of iodide involves the transport process. In conclusion, I- inhibited stimulation of glucose oxidation and 32P incorporation into phospholipids by all agonists, indicating that the effect is independent of the cAMP system and that iodide autoregulation does not only involve this system. Oxidation and organification of iodide are necessary for the inhibition.

• Research Organization: St. Luke's Episcopal Hospital, Houston, TX (USA)
• OSTI ID: 6170940
• Journal Information: Endocrinology; (United States), Journal Name: Endocrinology; (United States) Vol. 124:3; ISSN ENDOA
• Country of Publication: United States
• Language: English

Related Subjects

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560300* -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALDEHYDES
AMINES
AMP
ANIMALS
ANTI-INFECTIVE AGENTS
ANTIGENS
ANTIMICROBIAL AGENTS
AZINES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIOSYNTHESIS
BODY
CARBOHYDRATES
CARBON 14 COMPOUNDS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARCINOGENS
CHALCOGENIDES
CHLORIDES
CHLORINE COMPOUNDS
DAYS LIVING RADIOISOTOPES
DOGS
DRUGS
ENDOCRINE GLANDS
ESTERS
GLANDS
GLUCOSE
HALIDES
HALOGEN COMPOUNDS
HETEROCYCLIC COMPOUNDS
HEXOSES
HORMONES
INHIBITION
IODIDES
IODINE COMPOUNDS
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LIGHT NUCLEI
LIPIDS
MAMMALS
MATERIALS
METABOLISM
METHYLENE BLUE
MONOSACCHARIDES
NUCLEI
NUCLEOTIDES
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
ORGANIC SULFUR COMPOUNDS
ORGANS
OXIDES
OXYGEN COMPOUNDS
PEPTIDE HORMONES
PHENOTHIAZINES
PHORBOL ESTERS
PHOSPHOLIPIDS
PHOSPHORUS 32
PHOSPHORUS ISOTOPES
PITUITARY HORMONES
PROSTAGLANDINS
RADIOISOTOPES
SACCHARIDES
SYNTHESIS
THYROID
TOXIC MATERIALS
TOXINS
TRACER TECHNIQUES
TSH
VERTEBRATES