title: Involvement of dopamine in the differences in sexual behaviour between Roman high and low avoidance rats: an intracerebral microdialysis study.
abstract: Outbred Roman high- (RHA) and low-avoidance (RLA) rats are selected for respectively rapid vs. poor acquisition of the active avoidance response and display different copulatory patterns when exposed to a sexually receptive female, with RHA rats showing more robust sexual motivation and better performance than RLA rats also after repeated sexual activity. Here we show that the distinct patterns of sexual behaviour of the Roman lines are correlated with differences in the activity of the dopaminergic mesolimbic system, which plays a key role in sexual motivation and copulatory performance. Thus, differential increases in the concentrations of dopamine and its main metabolite 3,4-dihydroxyphenylacetic acid, occurred in dialysates obtained from the nucleus accumbens shell of naïve and sexually experienced Roman rats during the anticipatory and consummatory phases of sexual activity. These differences were particularly evident between sexually naïve RHA and RLA rats and tended to diminish but still persisted between sexually experienced rats, as did the differences in sexual behaviour. Analysis of the biochemical and behavioural findings showed that, while in RHA rats sexual experience caused a shift in the changes in both the dopaminergic activity and copulation towards the first period of the sexual test, in RLA rats sexual experience increased dopaminergic activity and copulation throughout the entire test. Therefore, this study adds experimental support to the view that the different sexual patterns of the Roman lines are due, at least in part, to a more robust functional tone of the mesolimbic dopaminergic system of RHA rats.
authors.affiliation: Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, Centre of Excellence for the Neurobiology of Addictions, University of Cagliari, 09042 Monserrato, Cagliari, Italy. Electronic address: fabrizio.sanna@unica.it.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Sanna
authors.affiliation: Department of Life and Environmental Sciences, Section of Pharmaceutical, Pharmacological and Nutraceutical Sciences, University of Cagliari, 09124 Cagliari, Italy.
authors.forename: Maria Antonietta
authors.initials: MA
authors.lastname: Piludu
authors.affiliation: Department of Life and Environmental Sciences, Section of Pharmaceutical, Pharmacological and Nutraceutical Sciences, University of Cagliari, 09124 Cagliari, Italy.
authors.forename: Maria Giuseppa
authors.initials: MG
authors.lastname: Corda
authors.affiliation: Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, Centre of Excellence for the Neurobiology of Addictions, University of Cagliari, 09042 Monserrato, Cagliari, Italy.
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Melis
authors.affiliation: Department of Life and Environmental Sciences, Section of Pharmaceutical, Pharmacological and Nutraceutical Sciences, University of Cagliari, 09124 Cagliari, Italy.
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Giorgi
authors.affiliation: Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, Centre of Excellence for the Neurobiology of Addictions, University of Cagliari, 09042 Monserrato, Cagliari, Italy; Institute of Neuroscience, National Research Council, Cagliari Section, 09042 Monserrato, Cagliari, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Argiolas
mesh_terms: D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000818:Animals; D001362:Avoidance Learning / Q000502:physiology*; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D008297:Male; D017551:Microdialysis; D009042:Motivation / Q000502:physiology; D009714:Nucleus Accumbens / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012726:Sexual Behavior, Animal / Q000502:physiology*; D013045:Species Specificity
chemical_list: D015102:3,4-Dihydroxyphenylacetic Acid; D004298:Dopamine
keywords: DOPAC; Dopamine; Microdialysis; Nucleus accumbens; Sexual behaviour