Regular Article

Cell and Tissue Research

, Volume 324, Issue 3, pp 535-546

First online:

Evidence for the presence of thyroid stimulating hormone, thyroglobulin and their receptors in Eisenia fetida: a multilevel hormonal interface between the nervous system and the peripheral tissues

  • Márta WilhelmAffiliated withInstitute of Physical Education and Sport Sciences, University of Pécs Email author 
  • , Anna KozaAffiliated withMTA-PTE Adaptation Biology Research Group, University of Pécs
  • , Péter EngelmannAffiliated withFaculty of Medicine, Department of Immunology and Biotechnology, University of Pécs
  • , Péter NémethAffiliated withFaculty of Medicine, Department of Immunology and Biotechnology, University of Pécs
  • , Mária CsoknyaAffiliated withDepartment of General Zoology and Neurobiology, University of Pécs

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

The present study describes the localization and distribution of thyroid-stimulating hormone (TSH), thyroglobulin (TGB) and their receptors in Eisenia fetida (Annelida, Oligochaeta) as revealed by immunohistological methods. Immunopositive neuronal and non-neuronal cells are present in both the central nervous system and some peripheral organs (e.g. foregut and coelomocytes). TSH- and TGB-immunopositive neurons in the various ganglia of the central nervous system are differentailly distributed. Most of the immunoreactive cells are found in the suboesophageal ganglion. The stained cells also differ in their shapes (round, oval, pear-shaped) and sizes (small, 12–25 μm; medium, 20–35 μm; large, 30–50 μm). In all ganglia of the central nervous system, TSH-positive neurons additionally show gamma aminobutyric acid (GABA) immunopositivity. Non-neuronal cells also take part in hormone secretion and transport. Elongated TSH-positive cells have been detected in the capsule of the central ganglia and bear granules or vacuoles in areas lacking neurons. Many of capillaries show immunoreactivity for all four tested antibodies in the entire central nervous system and foregut. Among the coelomocytes, granulocytes and eleocytes stain for TSH and its receptor and for TGB but not for thyroid hormone receptor. Most of the granulocytes are large (25–50 μm) but a population of small cells (10–25 μm) are also immunoreactive. None of the coelomocytes stain for GABA. We therefore suggest that the members of this hormone system can modify both metabolism and immune functions in Eisenia. Coelomocytes might be able to secrete, transport and eliminate hormones in this system.

Keywords

Earthworm TSH-TGB system GABA Immunocytochemistry Earthworm, Eisenia fetida (Annelida)