Effect of chronic glutamate administration to pregnant rats during gestation on metabotropic glutamate receptors from mothers and full-term fetuses brain.
Chronic glutamate treatment during gestational period caused a significant decrease in total metabotropic glutamate receptors (mGluR) number. Similar results were observed on the steady-state level of mGlu(1) receptor detected by immunoblotting assays, suggesting that this is the main receptor subtype modulated by agonist exposure. Furthermore, no variations on mRNA coding mGlu(1) receptor were found, suggesting post-transcriptional modulation as a possible mechanism of the lost of receptor detected at the membrane surface. On the other hand, western-blotting to determine level of G(q/11) protein and phospholipase C beta(1) revealed a significant decrease of both proteins in mothers brain. This decrease was associated with significant variation in glutamate and DHPG-stimulated phospholipase C activity. No significant differences on mGluR transduction pathway components were observed in fetuses brain. These results suggest that glutamate intake during pregnancy causes a down-regulation of different proteins involved in glutamate response mediated by mGluR only in mothers brain without significantly affecting fetuses brain.
León Navarro
D
D
Area de Bioquímica, Facultad de Químicas, Centro Regional de Investigaciones Biomédicas, Universidad de Castilla-La Mancha, Ciudad Real, Spain.
Albasanz
J L
JL
Iglesias
I
I
Ruiz
M A
MA
Martín
M
M
D000284:Administration, Oral; D000818:Animals; D001921:Brain / Q000378:metabolism; D001923:Brain Chemistry / Q000187:drug effects*; D015536:Down-Regulation / Q000187:drug effects*; D005260:Female; D005333:Fetus / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects*; D018698:Glutamic Acid / Q000008:administration & dosage*; D011247:Pregnancy; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar; D017470:Receptors, Glutamate / Q000096:biosynthesis*; D015398:Signal Transduction / Q000187:drug effects
D012333:RNA, Messenger; D017470:Receptors, Glutamate; D018698:Glutamic Acid