Rapid modulation of TRH-like peptides in rat brain by thyroid hormones.
Recent identification of membrane receptors for T4, T3, 3,5-T2, and 3-iodothyronamine that mediate rapid physiologic effects of thyroid hormones suggested that such receptors may supplement the regulation of TRH and TRH-like peptides by nuclear T3 receptors. For this reason 200 g male Sprague-Dawley rats received daily i.p. injections of PTU or T4. Levels of TRH and TRH-like peptides were measured 0, 2 h or 1, 2, 3, or 4 days later. Rapid increases or decreases in TRH and TRH-like peptide levels were observed in response to PTU and T4 treatments in various brain regions involved in mood regulation. Significant effects were measured within 2 h of T4 injection. Nuclear T3 receptor-mediated changes in gene expression altering translation, post-translational processing and constitutive release of peptides require more than 2 h. We conclude that non-genomic mechanisms may contribute to the psychiatric effects of thyroid disease and thyroid hormone adjuvant treatment for major depression.
Pekary
A Eugene
AE
Research Service, VA Greater Los Angeles Healthcare System, University of California, Bldg. 114, Rm. 229, 11301 Wilshire Blvd., Los Angeles, CA 90073, USA. Eugene.Pekary@med.va.gov
Sattin
Albert
A
Stevens
Schetema A
SA
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D002940:Circadian Rhythm; D008297:Male; D010455:Peptides / Q000737:chemistry*; D014176:Protein Biosynthesis; D011499:Protein Processing, Post-Translational; D051381:Rats; D017207:Rats, Sprague-Dawley; D013959:Thyroid Diseases / Q000378:metabolism; D013973:Thyrotropin-Releasing Hormone / Q000737:chemistry*; D013974:Thyroxine / Q000737:chemistry; D014284:Triiodothyronine / Q000737:chemistry
D010455:Peptides; D014284:Triiodothyronine; D013973:Thyrotropin-Releasing Hormone; D013974:Thyroxine