This paper is the 29th consecutive installment of the annual review of research concerning
the endogenous opioid system, now spanning 30 years of research. It summarizes papers …

Abstract Beta-endorphin (β-END) is an opioid neuropeptide which has an important role in
the development of hypotheses concerning the non-synaptic or paracrine communication of …

Orgasm is one of the most intense pleasures attainable to an organism, yet its underlying
mechanisms remain poorly understood. On the basis of existing literatures, this article …

Intraspecific communication involves the activation of chemoreceptors and subsequent
activation of different central areas that coordinate the responses of the entire organism …

There is increasing evidence that non-synaptic communication by volume transmission in
the flowing CSF plays an important role in neural mechanisms, especially for extending the …

Various lines of research indicate that sexual reward is mediated by opioids in both males
and females. In the first part I review basic ideas about sexual reward in humans followed by …

Aging is associated with compromised hippocampal function and reduced adult
neurogenesis in the dentate gyrus. As new neurons have been linked to hippocampal …

Sexual behavior is activated by motivation. An overwhelming majority of experimental
studies of the intricacies of sexual motivation has been performed in rodents, most of them in …

Normal or dysfunctional sexual behavior seems to be an important indicator of health or
disease. Many health disorders in male patients affect sexual activity by directly causing …

In rodents, sexual stimulation induces a positive affective state that is evaluated by the
conditioned place preference (CPP) test. Opioids are released during sexual behavior and …