The thyroid lobes: the different twins

Arch Biochem Biophys. 2012 Feb 1;518(1):16-22. doi: 10.1016/j.abb.2011.12.001. Epub 2011 Dec 9.

Abstract

Although differences in size of the right and left thyroid lobes are well defined, differences in morphology, follicles structure, cAMP production, thyrotropin receptor, and protein involved in cell signalling have not previously been reported. This study provides morpho-functional data of right and left thyroid lobes by biochemical, immunohistochemistry, immunoblotting and immunofluorescence analysis. We demonstrate that, in comparison with the left lobe, the right lobe has a higher activation index, is more sensitive to thyrotropin treatment, is rich in thyrotropin receptor and caveolin 1 involved in thyroid hormone synthesis as well as in epithelial thyroid cell homeostasis, is characterised by a high content of molecules involved in cell signalling such as stat3, raf1, sphingomyelinase and sphingomyelin-synthase whose activity ratio is necessary for epithelial cell activity and finally has more areas calcitonin-dependent. The relation between structure/function of right lobe and its susceptibility to the higher risk of pathological modifications with respect the left lobe is discussed.

MeSH terms

  • Animals
  • Caveolin 1 / metabolism
  • Cyclic AMP / metabolism
  • In Vitro Techniques
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Receptors, Thyrotropin / metabolism
  • Signal Transduction / drug effects
  • Sphingomyelin Phosphodiesterase / metabolism
  • Thyroid Gland / anatomy & histology*
  • Thyroid Gland / cytology
  • Thyroid Gland / drug effects
  • Thyroid Gland / metabolism*
  • Thyrotropin / pharmacology
  • Transferases (Other Substituted Phosphate Groups) / metabolism

Substances

  • Caveolin 1
  • Receptors, Thyrotropin
  • Thyrotropin
  • Cyclic AMP
  • Transferases (Other Substituted Phosphate Groups)
  • phosphatidylcholine-ceramide phosphocholine transferase
  • Sphingomyelin Phosphodiesterase