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Localization and role of leptin in the thyroid gland of the lizardPodarcis sicula (reptilia, lacertidae)
- Source :
- Journal of Experimental Zoology Part A: Comparative Experimental Biology. :628-634
- Publication Year :
- 2005
- Publisher :
- Wiley, 2005.
-
Abstract
- Leptin, the product of the ob gene, is a hormone secreted by adipocytes that regulates food intake and energy expenditure. The hypothalamus-pituitary-thyroid axis is markedly influenced by the metabolism status, being suppressed during food deprivation. The present study was designed to ascertain whether (1) lizard thyroid gland expresses the long form of leptin receptor (Ob-Rb) and (2) the leptin administration affects the thyroid gland activity in this species (and to verify whether leptin plays a similar role in reptiles as observed in the other vertebrates). The presence of leptin receptor in the thyroid gland of Podarcis sicula was demonstrated by immunohistochemical technique (avidin-biotin-peroxidase complex--ABC method). The role of leptin in the control of thyroid gland activity was studied in vivo using light microscopy (LM) technique coupled to a specific radioimmunoassay for thyroid-stimulating hormone (TSH) and thyroid hormones (T4 and T3). Leptin (0.1 mg/100 g body wt)/day increased T4 and T3 release for 3 days but decreased the plasma concentration of TSH; using LM clear signs of stimulation in the thyroid gland were observed. These findings suggest that systemic administration of leptin stimulates the morphophysiology of the thyroid gland in the lizard through a direct mechanism involving Ob-Rb.
- Subjects :
- Leptin
Male
endocrine system
medicine.medical_specialty
endocrine system diseases
Thyroid Gland
Thyrotropin
Receptors, Cell Surface
Stimulation
Reptilian Proteins
Biology
Internal medicine
medicine
Animals
Receptor
Leptin receptor
Triiodothyronine
digestive, oral, and skin physiology
Podarcis
Thyroid
Lizards
biology.organism_classification
Thyroxine
Endocrinology
medicine.anatomical_structure
Receptors, Leptin
Animal Science and Zoology
hormones, hormone substitutes, and hormone antagonists
Hormone
Subjects
Details
- ISSN :
- 1552499X and 15488969
- Database :
- OpenAIRE
- Journal :
- Journal of Experimental Zoology Part A: Comparative Experimental Biology
- Accession number :
- edsair.doi.dedup.....9a5692bee3f47fda9448c7e746d40cb6