Higher expression of alpha7 nicotinic acetylcholine receptors in human fetal compared to adult brain.
Neuronal nicotinic acetylcholine receptors are thought to be involved in regulation of several processes during neurogenesis of the brain. In this study the expression of the alpha7 nicotinic acetylcholine receptor subtype was investigated in human fetal (9-11 weeks of gestation), middle-aged (28-51 years) and aged (68-94 years) medulla oblongata, pons, frontal cortex, and cerebellum. The specific binding of the alpha7 receptor antagonist [(125)I]alpha-bungarotoxin was significantly higher in fetal than in both middle-aged and aged medulla oblongata and aged pons. No significant decrease in [(125)I]alpha-bungarotoxin binding sites was observed from fetal to adult cortex and cerebellum. The alpha7 mRNA expression was significantly higher in all fetal brain regions investigated, except for aged cortex, than in corresponding middle-aged and aged tissue. The high expression of alpha7 nicotinic acetylcholine receptors in fetal compared to adult brain supports the view that these receptors play an important role during brain development.
Falk
Lena
L
Neurotec Department, Division of Molecular Neuropharmacology, Huddinge University Hospital, S-141 86, Stockholm, Sweden.
Nordberg
Agneta
A
Seiger
Ake
A
Kjaeldgaard
Anders
A
Hellström-Lindahl
Ewa
E
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000235:genetics / Q000378:metabolism; D001665:Binding Sites / Q000235:genetics; D001667:Binding, Competitive / Q000187:drug effects / Q000235:genetics; D001921:Brain / Q000166:cytology / Q000196:embryology* / Q000378:metabolism*; D002038:Bungarotoxins; D002454:Cell Differentiation / Q000235:genetics*; D021983:Cyclophilins / Q000235:genetics; D005260:Female; D005333:Fetus; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008875:Middle Aged; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D011180:Postmortem Changes; D012333:RNA, Messenger / Q000378:metabolism; D011869:Radioligand Assay; D011978:Receptors, Nicotinic / Q000235:genetics*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D015854:Up-Regulation / Q000235:genetics*; D064569:alpha7 Nicotinic Acetylcholine Receptor
D002038:Bungarotoxins; C579167:Chrna7 protein, human; D007457:Iodine Radioisotopes; D012333:RNA, Messenger; D011978:Receptors, Nicotinic; D064569:alpha7 Nicotinic Acetylcholine Receptor; D021983:Cyclophilins