Psychobiological Investigation on Sociosexual Behavior in Male: Preclinical and Clinical Studies

Abstract

The results of several recent epidemiological surveys, shows that male sexual dysfunctions (e.g. erectile dysfunction and premature ejaculation) are extremely prevalent in the general population. These sexual disorders are strongly associated with aging and are influenced by a variety of medical, psychiatric, life style factors and have a significant relationship with mood, state and interpersonal functioning and overall quality of life. An emerging point of view in the last two decade shows that a combination of psychological (e.g. temperamental and personality trait), physiological (e.g. endocrine data) and ecological (e.g. social status) variables seem to be the most relevant factors to explain the develop of this difficulties. Recent epidemiological paper point out the relationships between depression, low dominance score and erectile dysfunctions. In this context, the rank theory of depression (known also as defeat theory or resource loss theory) suggests that depression is highly correlated with perceptions of low rank and subordinate status. In fact depressed people has a degree of inhibition in engagement in certain social activities, see themselves as inferior to others and tend to behave submissively, all variables also associated with anxiety, especially social anxiety as a specific stressor. Under this respect in animal species a recurring factor, as the exposure to chronic social stress has been associated with many systemic and behavioural disorders. However, being exposed to social stress does not necessarily predict subsequent pathological consequences, in fact social factors (i.e. dominance and submission) are a key factor in individual disease susceptibility. The aim of this thesis is to investigate the impact of social stress such as defeat and loss of rank on male mice sexual behavior and tentatively compare preliminary human clinical data supporting the view that loss of resource and/or rank is a critical factor in the development of sexual dysfunction accompanied by depressive state .