Changes of phorbol ester binding sites in rat brain following intracerebroventricular administration of thyrotropin-releasing hormone (TRH): an in vitro macroautoradiographic investigation.
We examined the influence of the intracerebroventricular (icv) administration of thyrotropin-releasing hormone (TRH) on protein kinase C (PKC) activities in various rat forebrain regions in order to cast light on the mechanism of extra-pituitary non-endocrine physiological actions of TRH in the central nervous system. An in vitro macroautoradiographic method, with [3H]phorbol 12, 13-dibutyrate (PDBu) as the radioactive ligand, was used to investigate quantitative alterations of PKC activities. The optical densities for PDBu binding sites in the striatum and hippocampal formation were significantly increased after the icv administration of TRH, while those in the frontal cortex and septum were unchanged. These findings suggest that TRH may exert some of its non-endocrine functions through striatal and hippocampal neurons which used PKC in their second messenger systems.
Mizukawa
K
K
Department of Anatomy, Okayama University Medical School, Japan.
Otsuka
N
N
Ogawa
N
N
Haba
K
K
Mori
A
A
D000818:Animals; D001345:Autoradiography; D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; D007276:Injections, Intraventricular; D008297:Male; D015240:Phorbol 12,13-Dibutyrate; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D011955:Receptors, Drug / Q000187:drug effects*; D013973:Thyrotropin-Releasing Hormone / Q000008:administration & dosage*
D029742:Caenorhabditis elegans Proteins; D002352:Carrier Proteins; D011955:Receptors, Drug; C083141:phorbol ester binding protein; C027776:phorbol ester receptor; D015240:Phorbol 12,13-Dibutyrate; D013973:Thyrotropin-Releasing Hormone; D011493:Protein Kinase C