Abstract

Objective To observe the effects of fluoride on thyroid morphology,thyroid peroxidase and serum thyroid hormones.

Methods One – month ablactating SD rats were randomly divided into three groups:the control group, low-fluoride group, middle-fluoride group, high-fluoride group, fed with water containing different fluoride concentration by adding NaF respectively. Rats were sacrificed after being fed for six months. The morphology of thyroid was observed through light microscope. The TPO activity was measured with upgrade guaiacol method. Radio-immunoassay was used to detect serum thyroid hormones.

Results The major changes included increased follicles with colloid accumulation in high fluoride groups. With the dose of fluoride increasing, TPO activity significantly decreased as compared with the control group (P0.05). FT4 levels of the high-fluoride group were significantly lower compared with the control group (P0.05).

Conclusions Chronic fluoride excess leads to definite histological changes in rat thyroid, inhibiting TPO activity so that level of thyroid hormone is decreased, which shows that fluoride can cause goiter, and cause abnormal changes of thyroid metabolism function.

• Related Studies :

  • Comparison of the effects of various agents on thyroidal adenyl cyclase activity with their effects on thyroid hormone release

    Intact mouse thyroid glands were used to measure the formation of cyclic [3H]AMP from [3H]adenine, and the release of thyroidal iodine. These two parameters of thyroid activity responded to similar concentrations of thyroid-stimulating hormone (TSH). Both were stimulated by prostaglandin E1, although the response was always very much less than

  • Is water fluoridation a hidden cause of obesity? Histological study on thyroid follicular cells of albino rats

    Introduction: Fluoride in drinking water is known to exert both beneficial and detrimental effects on health. When consumed in excess, it is known to cause adverse effects including dental fluorosis, hip fracture, bone cancer, lower intelligence, and kidney toxicity plus goiter. Aim: This study was carried out to determine the histological

  • y-Aminobutyric acid ameliorates fluoride-induced hypothyroidism in male kunming mice

    AIM:  This study evaluated the protective effects of y-aminobutyric acid (GABA), a non-protein amino acid and anti-oxidant, against fluoride-induced hypothyroidism in mice. MAIN METHODS:  light microscope sample preparation technique and TEM sample preparation technique were used to assay thyroid microstructure and ultrastructure; enzyme immunoassay method was used to assay hormone and

  • Effects of fluoride on growth and thyroid function in young pigs.

    This study was undertaken to investigate the effects of fluoride on growth and thyroid function in young pigs. Three groups of eight crossbred barrows were exposed to 100, 250, and 400 mg F– /kg (from NaF) in their diets for 50 days. Compared to a control group of eight pigs,

  • Ameliorative effect of resveratrol against fluoride-induced alteration of thyroid function in male wistar rats

    Resveratrol (3,4,5-trihydroxystilbene), a polyphenol and well-known natural antioxidant has been evaluated for its protective effect against fluoride-induced metabolic dysfunctions in rat thyroid gland. Fluoride, the most abundant anions present in groundwater throughout the world, creates a major problem in safe drinking water and causes metabolic, structural, and functional injuries in

• Related FAN Content :

  • Fluoride's Impact on Thyroid Hormones

    Up through the 1950s, doctors in Europe and South America prescribed fluoride for this purpose in patients with hyperthyroidism. (Merck Index 1968). Fluoride was selected as a thyroid suppressant based on findings dating back to the mid-19th century that fluoride is a goitrogen (a substance that can cause goiter). When used as

  • The Relationship Between Fluoride Exposure & Goitre in South Africa

    As a general rule simple goitre, irrespective of the cause, can be very, or fairly, satisfactorily combated by an adequate increase in man's daily iodine intake, except when the enlargement of the gland is due to the ingestion of excessive amounts of fluorine. The only correct solution to fluorine-induced endemic goitre is the removal of this element from the drinking water.

  • Fluoride Exposure Aggravates the Impact of Iodine Deficiency

    A consistent body of animal and human research shows that fluoride exposure worsens the impact of an iodine deficiency. Iodine is the basic building block of the T3 and T4 hormones and thus an adequate iodine intake is essential for the proper functioning of the thyroid gland. When iodine intake is inadequate during infancy and

  • Fluoride, Water Hardness, and Endemic Goitre

    Variations in goitre prevalence were found to correlate closely with the fluoride content (p=0-74; P<0-01) and with the hardness (p=0.77; P<0-01) of the water in each village. The effects of fluoride and water hardness seem to be independent.

  • Fluoride Aggravates Thyroid Damage Caused by Excess Iodine Intake

    Chinese researchers have found that the combination of excess fluoride with excess iodine caused greater reductions in IQ, or greater increases in goitre than either scenario by itself.