title: Differential contribution of Gαi/o subunits in the response to food deprivation.
abstract: Behavioral responses to food deprivation are a fundamental aspect of nervous system function in all animals. Several signaling molecules in the mammalian brain act through G proteins of the Gi/o family to mediate response to food restriction. The present study examined whether food intake changes under a condition of little stimulation to eat, such as that elicited by 4h of food deprivation, was altered by Gi/o isoform silencing induced by intracerebroventricular (i.c.v.) administration of antisense oligodeoxynucleotides (aODN) against the α subunit of Gi1, Gi2, Gi3, Go1 and Go2. The effect of aODN pretreatments on food intake was evaluated 15, 30, 45, and 60min after food re-administration. Selective effects were noted on food intake with anti-Giα1 (3.12-25nmol), Giα3 (1.56-12.5nmol) and Goα2 (3.12-25nmol) aODN exerting increase in food consumption, while anti-Giα2 (3.12-25nmol) and Goα1 (3.12-25nmol) aODN exerting decrease in food consumption. We observed the effect of the α-subunit silencing on food consumption as soon as 15min after food readministration, that was still significant after 60min. At the highest effective doses, different for each anti-Gαi/o subunit, any treatment did not impair motor coordination, nor modified spontaneous mobility and exploratory activity. These results indicate a relevant distinction between Gαi/o subunits on feeding behavior, and suggest that Gi/o proteins are critical for the integrative modulation of normal feeding behavior. Changes in Gi/o protein activity may be associated with modifications of feeding.
authors.affiliation: Laboratory of Neuropsychopharmacology, Department of Neurosciences, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology, University of Florence, Florence, Italy. Electronic address: maria.sanna@unifi.it.
authors.forename: Maria Domenica
authors.initials: MD
authors.lastname: Sanna
authors.affiliation: Laboratory of Neuropsychopharmacology, Department of Neurosciences, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology, University of Florence, Florence, Italy.
authors.forename: Carla
authors.initials: C
authors.lastname: Ghelardini
authors.affiliation: Laboratory of Neuropsychopharmacology, Department of Neurosciences, Psychology, Drug Research and Child Health (NEUROFARBA), Section of Pharmacology, University of Florence, Florence, Italy.
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Galeotti
mesh_terms: D000818:Animals; D004435:Eating; D005215:Fasting; D005247:Feeding Behavior; D005508:Food Deprivation; D019206:GTP-Binding Protein alpha Subunits, Gi-Go / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D009043:Motor Activity; D016376:Oligonucleotides, Antisense / Q000235:genetics
chemical_list: D016376:Oligonucleotides, Antisense; D019206:GTP-Binding Protein alpha Subunits, Gi-Go
keywords: Antisense oligodeoxynucleotides; Food deprivation; Gi/o-proteins