Immunohistochemical localization of gastrin-releasing peptide receptor in the mouse brain.
Gastrin-releasing peptide (GRP) is a mammalian bombesin (BN)-like peptide that binds with high affinity to the GRP receptor (GRP-R). Previous behavioral studies using mice and rats showed that the GRP/GRP-R system mediates learning and memory by modulating neurotransmitter release in the local GABAergic network of the amygdala and the nucleus tractus solitarius (NTS). To date, the precise distribution of GRP-R in the brain has not been elucidated. We used a synthetic peptide derived from mouse GRP-R to generate affinity-purified antibodies to GRP-R and used immunohistochemistry to determine the distribution of GRP-R in the mouse brain. The specificity of anti-GRP-R antibody was confirmed in vitro using COS-7 cells transiently expressing GRP-R and in vivo using GRP-R-deficient and wild-type mouse brain sections. GRP-R immunoreactivity was widely distributed in the isocortex, hippocampal formation, piriform cortex, amygdala, hypothalamus, and brain stem. In particular, GRP-R immunoreactivity was observed in the lateral (LA), central, and basolateral amygdaloid (BLA) nuclei and NTS, which are important regions for memory performance. Double-labeling immunohistochemistry demonstrated that subpopulations of GRP-R are present in GABAergic neurons in the amygdala. Consequently, GRP-R immunoreactivity was observed in the GABAergic neurons of the limbic region. These anatomical results provide support for the idea that the GRP/GRP-R system mediates memory performance by modulating neurotransmitter release in the local GABAergic network.
Kamichi
Sari
S
Department of Cell Biology, School of Human Sciences, Waseda University, 2-579-15, Mikajima, Tokorozawa, Saitama 359-1192, Japan.
Wada
Etsuko
E
Aoki
Shunsuke
S
Sekiguchi
Masayuki
M
Kimura
Ichiro
I
Wada
Keiji
K
D000818:Animals; D000906:Antibodies / Q000737:chemistry / Q000378:metabolism; D000918:Antibody Specificity; D001921:Brain / Q000033:anatomy & histology / Q000378:metabolism*; D019556:COS Cells; D002522:Chlorocebus aethiops; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D005968:Glutamate Decarboxylase / Q000378:metabolism; D007150:Immunohistochemistry / Q000379:methods*; D007527:Isoenzymes / Q000378:metabolism; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D018004:Receptors, Bombesin / Q000172:deficiency / Q000276:immunology / Q000378:metabolism*; D014162:Transfection / Q000379:methods
D000906:Antibodies; D005904:Glial Fibrillary Acidic Protein; D007527:Isoenzymes; D008869:Microtubule-Associated Proteins; C079240:Mtap2 protein, mouse; D018004:Receptors, Bombesin; D005968:Glutamate Decarboxylase; C402565:glutamate decarboxylase 1; D010751:Phosphopyruvate Hydratase