These experiments were designed to evaluate the hypothesis that fluoxetine-induced sexual dysfunction in female rats derived from disruption of neuroendocrine events that normally facilitate sexual behavior. If so, exogenous hormonal priming to ovariectomized rats should eliminate fluoxetine's effect. Ovariectomized rats were subchronically treated with 10 mg/kg fluoxetine or distilled/deionized water vehicle for 9 consecutive days. On the 8 th day of treatment, rats were primed with 10 μg estradiol benzoate followed 48 hr later with 500 μg progesterone. In a pretest for sexual behavior on the 10 th day, there was no difference between subchronic treatments. Sexual receptivity was again monitored 30 min after injection on the 10 th day (acute treatment) with distilled/deionized water, 10 mg/kg fluoxetine or 20 mg/kg fluoxetine. Thereafter, the female's behavior was monitored for 20 min in a male preference procedure. After the acute treatment in rats subchronically treated with water, fluoxetine (10 or 20 mg/kg) significantly reduced both lordosis frequency and quality and reduced (but not significantly) time spent with the male. In rats subchronically treated with fluoxetine, the lordosis-inhibiting effect of an acute injection with fluoxetine was significantly attenuated relative to that of the subchronically water-treated rats. In contrast to expectation, subchronic treatment with fluoxetine increased, rather than reduced, the relative time females spent near the male. Activity, as measured by center crossings, and grooming were also reduced by subchronic treatment with fluoxetine.
KeywordsSSRI; sexual motivation; lordosis; subchronic
IntroductionFluoxetine (Prozac®) is frequently prescribed for depression as well as for a variety of other disorders such as premenstrual dysphoria, anxiety, anorexia and bulemia which are more prevalent in females than in males [4,19,22,33]. A reported undesirable side effect of fluoxetine, as well as other selective serotonin reuptake inhibitors (SSRIs), is a high incidence of sexual dysfunction [8,15,28]. Although such sexual dysfunction occurs in both genders, more experimental emphasis has been placed on identifying the responsible mechanisms in males than in females [17]. Yet, as much as 32% of female patients may experience SSRI-*Corresponding author Department of Biology, Texas Woman's University, Denton, TX 76204, Phone: 940-898-2356, FAX: 940-898-2382.edu. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. [32]. The mechanisms responsible for such drug-induced sexual dysfunction in females have been difficult to identify,...