Effect of olfactory bulbectomy on adenylyl cyclase activity in the limbic system.
Monoaminergic neurotransmission is a key element in the physiopathology of depressive disorders, but information is still sparse on animal models of this disease. Here, we used the olfactory bulbectomy (OBX) model of depression to characterize cAMP-second messenger signaling pathways, i.e., adenylyl cyclase activity (basal, sodium fluoride (NaF)- and forskolin-stimulated conditions) as well as Gi and Gs protein levels in different regions of the limbic system. Two weeks after surgery and compared to sham controls, OBX rats displayed reduced NaF-stimulated adenylyl cyclase activity and increased Gi/Gs ratios in the hypothalamus, pre-frontal and cingulate cortices but not in the amygdala, hippocampus and caudate nucleus. No differences were found in basal or forskolin-stimulated conditions. The observed reduction of adenylyl cyclase activity induced by NaF and the increase in the Gi/Gs ratio could explain the changes in neurotransmission in OBX rats as well as in humans with depression.
Wann
Boubacar Pasto
BP
Centre de Recherche, Hôpital du Sacré-Coeur de Montréal, Canada.
D'Anjou
Brian
B
Bah
Thierno Madjou
TM
Webster
Harry H
HH
Godbout
Roger
R
Rousseau
Guy
G
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D015153:Blotting, Western; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D003866:Depressive Disorder / Q000503:physiopathology; D004195:Disease Models, Animal; D020536:Enzyme Activators / Q000494:pharmacology; D019204:GTP-Binding Proteins / Q000378:metabolism; D008032:Limbic System / Q000201:enzymology*; D008297:Male; D009830:Olfactory Bulb / Q000502:physiology* / Q000601:surgery; D051381:Rats; D017207:Rats, Sprague-Dawley; D015290:Second Messenger Systems; D012969:Sodium Fluoride / Q000494:pharmacology
D020536:Enzyme Activators; D005576:Colforsin; D012969:Sodium Fluoride; D000242:Cyclic AMP; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases