Expression of TRH and TRH-like peptides in a human glioblastoma-astrocytoma cell line (U-373-MG).
The human glioblastoma-astrocytoma cell line U-373-MG shows morphological features typical of its neuroectodermal origin. Cells showed positive immunostaining for the glial fibrillary acidic protein. We used this cell culture for studying the putative production of TRH and TRH-related peptides. In a cell extract and conditioned medium, cation and anion exchange chromatography and HPLC revealed the presence of TRH and acidic TRH-like peptides which were identified, at least in part, as pGlu-Glu-ProNH(2). These findings demonstrated that U-373-MG cells are able to produce and release these peptides. Further evidence of TRH synthesis was obtained by amplification using RT-PCR of a 396 bp fragment that corresponds to the TRH precursor mRNA. Our results therefore suggest that the U-373-MG cell line may be a useful model for studying the regulation of TRH and TRH-related peptide production and the interaction of these peptides with other classical neurotransmitter systems. In fact, pilocarpine (a muscarinic cholinergic agonist) enhanced and nicotine (a nicotinic cholinergic agonist) decreased TRH and TRH-related compound production by this cell line. These data also point out that glia may produce substances with neuromodulatory action.
García
S I
SI
Departamento de Sustancias Vasoactivas y Laboratorio de Cardiología Molecular, Instituto de Investigaciones Médicas 'A. Lanari', Facultad de Medicina, Combatientes de Malvinas 3150, Buenos Aires 1427, Argentina. sigryc@elsitio.net
Porto
P I
PI
Martinez
V N
VN
Alvarez
A L
AL
Finkielman
S
S
Pirola
C J
CJ
D000704:Analysis of Variance; D001254:Astrocytoma / Q000737:chemistry* / Q000378:metabolism; D001932:Brain Neoplasms / Q000737:chemistry* / Q000378:metabolism; D002490:Central Nervous System / Q000378:metabolism; D002848:Chromatography, DEAE-Cellulose; D002851:Chromatography, High Pressure Liquid; D002852:Chromatography, Ion Exchange; D005909:Glioblastoma / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D008954:Models, Biological; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives; D012333:RNA, Messenger / Q000032:analysis; D011863:Radioimmunoassay; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013973:Thyrotropin-Releasing Hormone / Q000031:analogs & derivatives / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D014407:Tumor Cells, Cultured / Q000737:chemistry / Q000378:metabolism
D012333:RNA, Messenger; D013973:Thyrotropin-Releasing Hormone; C059697:pyroglutamyl-glutamyl-proline amide; D011761:Pyrrolidonecarboxylic Acid