EXPRESSION OF NEI, TH AND TRH-R1 IN HYPOTHALAMIC AREAS OF ADULT MALE RATS: REGULATION BY THYROID HORMONES

AYALA CAROLINA; PENNACCHIO GISELA E; SOAJE MARTA; SELTZER ALICIA M; CELIS MARÍA ESTER; JAHN GRACIELA A; VALDEZ, SUSANA R

San Luis

Congreso; Sociedad de Biología de Cuyo; 2014

Sociedad de Biología de Cuyo

&amp;amp;lt;!-- /* Font Definitions */@font-face{font-family:Calibri;panose-1:2 15 5 2 2 2 4 3 2 4;mso-font-charset:0;mso-generic-font-family:auto;mso-font-pitch:variable;mso-font-signature:3 0 0 0 1 0;} /* Style Definitions */p.MsoNormal, li.MsoNormal, div.MsoNormal{mso-style-parent:"";margin-top:0cm;margin-right:0cm;margin-bottom:10.0pt;margin-left:0cm;line-height:115%;mso-pagination:widow-orphan;font-size:11.0pt;font-family:"Times New Roman";mso-ascii-font-family:Calibri;mso-fareast-font-family:Calibri;mso-hansi-font-family:Calibri;mso-bidi-font-family:"Times New Roman";mso-ansi-language:EN-US;mso-fareast-language:EN-US;}@page Section1{size:612.0pt 792.0pt;margin:70.85pt 3.0cm 70.85pt 3.0cm;mso-header-margin:36.0pt;mso-footer-margin:36.0pt;mso-paper-source:0;}div.Section1{page:Section1;}--&amp;amp;gt;Neuropeptideglutamic acid-isoleucine-amide (NEI) is a 13th-amino acid peptide. Bothlow and high levels of thyroid hormones (THs) modify NEI concentration inhypothalamic areas involved in the regulation of reproduction and certainbehaviors in adult male and female rats. NEI activates the dopaminergic system inducinglocomotor activity and excessive grooming behavior in the rat. In the presentstudy we explored the effects of THs levels on NEI, Tyrosine Hydroxilase (TH,limiting enzyme of dopamine biosynthesis) and TRH Receptor 1 (TRH-R1) mRNA expressionin the peduncular part of the lateral hypothalamus (PLH), preoptic area (POA) andarcuate nucleus (ARC) of male Wistar control (Co), hypothyroid (HypoT: 0.1 g/LPTU in drinking water) and hyperthyroid (HyperT: T4, 250 µg/kg/day,sc) rats sacrificed after 21 days of treatment or vehicle administration.Hypothalamic areas were dissected and gene expression was measured by real time RT-PCR. One way ANOVAanalysis was performed. PLH NEI expression increased in treated groups(p<0.05 vs Co) and remained constant in POA and ARC. HypoT-POA TH mRNA wasincreased compared to HyperT (p<0.05). HyperT-ARC TH expression increasedcompared to Co (p<0.05). No changes in TH levels were observed in PLH.  HypoT-POA TRH-R1 levels increasedcompared to Co and HyperT (p<0.05), no changes were observed in the otherareas. These results show that NEI and TH mRNA are located in regions with neuronalterminals but their expression is regulated by THs at soma level (PLH and ARCrespectively). Major changes on TRH-R1 were found in POA. This evidences thecomplex regulation exerted by THs on different hypothalamic areas and supportother results obtained by IF showing the complex interaction of differentcomponents involved in the regulation of reproduction and certain behaviors.