vasoactive-intestinal-peptide and Sexual-Dysfunctions--Psychological

Dysfunction of female sexual desire, arousal, or orgasm affects approximately 30% of women. Early attempts to treat female sexual dysfunction arose out of programs developed for male erectile dysfunction and have proven largely unsuccessful. A new wave of targets is now being pursued; many of these targets are postulated to modulate central pathways. Classical neurotransmitter systems, such as dopamine and serotonin, as well as the neuropeptide melanocortin, are receiving the most attention. Early clinical data look promising; however, clinical trial methodology in female sexual dysfunction is not well developed and only further testing will determine whether these treatments meet regulatory hurdles and satisfy patient need.

Topics: Alprostadil; Dopamine Agonists; Drug Design; Female; Humans; Neprilysin; Phosphodiesterase 5 Inhibitors; Receptors, Melanocortin; Serotonin 5-HT1 Receptor Agonists; Sexual Dysfunction, Physiological; Sexual Dysfunctions, Psychological; Vasoactive Intestinal Peptide

Evidence concerning pharmacological effects on human sexuality suggests that dopaminergic receptor activation may be associated with penile erection. Erection also appears to involve inhibition of alpha-adrenergic influences and beta-adrenergic stimulation plus the release of a noncholinergic vasodilator substance, possibly vasoactive intestinal peptide. Ejaculation appears to be mediated primarily by alpha-adrenergic fibers. Serotonergic neurotransmission may inhibit the ejaculatory reflex. An understanding of the neurobiological substrate of human sexuality may assist clinicians in choosing psychotropic agents with minimal adverse effects on sexual behavior and may also contribute to the development of pharmacological interventions for sexual difficulties.

Topics: Ejaculation; Humans; Male; Penile Erection; Psychotropic Drugs; Receptors, Dopamine; Sexual Behavior; Sexual Dysfunctions, Psychological; Vasoactive Intestinal Peptide

Female sexual arousal disorder (FSAD) is the inability to attain or maintain an adequate lubrication-swelling response of sexual excitement. The potentiation of vascular responses leading to increased blood flow in clitoris and vagina has represented the main focus in the pharmacological treatment of FSAD, including the evaluation of the type 5 phosphodiesterase (PDE5) inhibitors. However, due to a lack of clear efficacy, there is no approved pharmacotherapy for FSAD to date. In the present issue of the British Journal of Pharmacology, Wayman et al. show that the administration by intravenous or intravaginal routes of a novel neutral endopeptidase inhibitor, UK-414,445, results in enhanced genital blood flow responses to pelvic nerve stimulation in female rabbits, without significantly affecting blood pressure. Neutral endopeptidase inhibition, by preserving vasoactive peptides such as vasoactive intestinal polypeptide, raises the possibility of a new pharmacological approach to the treatment of FSAD.

Topics: Animals; Electric Stimulation; Female; Genitalia, Female; Neprilysin; Pelvis; Pentanoic Acids; Rabbits; Regional Blood Flow; Sexual Behavior, Animal; Sexual Dysfunctions, Psychological; Thiadiazoles; Vasoactive Intestinal Peptide

Gabapentin has been used effectively for neuropathic pain with mild side effects. Two cases of gabapentin-induced sexual dysfunction are reported and discussed.

Topics: Adolescent; Amines; Analgesics; Cyclohexanecarboxylic Acids; Female; Gabapentin; gamma-Aminobutyric Acid; Humans; Libido; Male; Middle Aged; Neuralgia; Nitric Oxide; Peripheral Nerves; Peripheral Nervous System Diseases; Sexual Dysfunction, Physiological; Sexual Dysfunctions, Psychological; Up-Regulation; Vasoactive Intestinal Peptide; Weight Gain; Withholding Treatment