Royal society homepage skip to main page content home current issue past issues submit subscribe alerts about us help contact us feedback sitemap positron emission tomography imaging studies of dopamine receptors in primate models of addiction michael a nader *, paul w czoty , robert w gould and natallia v riddick department of physiology and pharmacology, wake forest university school of medicine 546 nrc, medical center boulevard, winston-salem, nc 27157-1083, usa author for correspondence ( mnader{at}wfubmc. Viagra side effects women urdu viagra pills how much Edu ) abstract animal models have provided valuable information related to trait and state variables associated with vulnerability to drug addiction. buy viagra discount online Our brain imaging studies in monkeys have implicated d2 receptors in cocaine addiction. buy cheap viagra canada buy viagra in the united states For example, an inverse relationship between d2 receptor availability and rates of cocaine self-administration has been documented. generic viagra without a prescription where to buy non prescription viagra Moreover, environmental variables, such as those associated with formation of the social hierarchy, can impact receptor availability and sensitivity to the abuse-related effects of cocaine. buy generic viagra on line can buy viagra tesco Similarly, both d2 receptor availability and cocaine self-administration can be altered by chronic drug administration and fluctuations in hormone levels. buy generic viagra In addition, cocaine self-administration can be altered in an orderly fashion by presentation of an acute stressor, such as acting as an intruder into an unfamiliar social group, which can shift the cocaine dose–response curve to the left in subordinate monkeys and to the right in dominant animals, suggesting an interaction between social variables and acute stressors. viagra tablets online uk Conversely, irrespective of social rank, acute environmental enrichment, such as increasing the size of the living space, shifts the cocaine dose–response curve to the right. viagra generique 40 These findings highlight a pervasive influence of the environment in modifying the reinforcing effects of cocaine and strongly implicate brain d2 receptors. viagra pills how much Keywords: dopamine d2 receptors cocaine self-administration social behaviour animal models non-human primates footnotes one contribution of 17 to a discussion meeting issue ‘the neurobiology of addiction: new vistas’. Viagra daily use side effects ⩠2008 the royal society citeulike connotea delicious digg facebook google+ twitter what's this? viagra side effects antifungal ⫠previous | next article ⻠table of contents this is one article from the discussion meeting. viagra pills how much Price comparison viagra viagra