Monoaminergic influences on temporal patterning of sexual behavior in male rats

We evaluated the effects of the serotonin (5-HT) presynaptic uptake blocker fluoxetine (FLX) and the dopamine (DA)/noradrenaline (NE) releaser amantadine (AMA), separately and in combination, on the temporal patterning of male rat sexual behavior. FLX alone increased intermount-bout intervals, time-outs, grooming time, ejaculation latency, number of mounts per mount bout, and number of mount bouts per ejaculation. AMA alone had the opposite effect on these measures. Additionally, AMA, when given in combination with FLX, completely reversed the FLX-induced deficits in copulatory behavior. We interpret our results as suggesting an interaction between 5-HT and catecholamines in the temporal patterning of male rat copulatory behavior.     

Neural mediation of estrogen-dependent courtship behavior in female ring doves.

Investigated the role played by the preoptic-hypothalamic region in the mediation of female ring dove courtship behavior. In Exp I, 43 ovariectomized Ss were tested in response to estradiol benzoate (EB) injections both before and after preoptic area (POA), posterior medial hypothalamus (PMH), or sham lesions. Only the PMH group's behavior significantly declined following lesions. Exp II, with 46 Ss, examined whether intracranial EB implants would be effective in stimulating courtship behavior in ovariectomized Ss. Unilateral EB implants were placed throughout the hypothalamic region, including rostral to the anterior preoptic and caudal to the PMH. Implants in the PMH were most effective in stimulating behavior. Results indicate the importance of the PMH in mediation of estrogen-dependent courtship behavior and are analogous to recent findings concerning the role of the ventromedial hypothalamus in mammalian female sexual behavior. (35 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Patient sexual behavior and sexual harassment: A national survey of female psychologists.

A nationwide survey of 750 female psychologists practicing psychotherapy was conducted to determine the incidence of sexual harassment and potentially sexualized patient behaviors in clinical practice. A usable return rate of 48.7% was obtained (N?=?354). A total of 53.7% of the respondents reported at least 1 incident of sexual harassment. Events ranged from inappropriate verbal remarks to sexual assaults. Respondents reported an even higher incidence of sexually suggestive patient behaviors in clinical practice, although most of these were not experienced as sexual harassment. Implications for training and practice are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cholinergic influences on estrogen-dependent sexual behavior in female rats.

Examined the ability of cholinergic agents to influence hormone-dependent sexual behavior in Sherman rats. In Exp I, sexual behavior, indicated by the incidence of lordosis, was significantly increased in estrogen-treated Ss following bilateral infusion of a cholinergic receptor agonist, carbachol (.5 μg/cannula) into the medial preoptic area of the brain. Infusion of an artificial cerebrospinal fluid vehicle failed to facilitate lordosis. The incidence of lordosis was normally highest 15 min after carbachol infusion began to wane by 45 min, and had returned to control levels by 90 min. Centrally administered carbachol activated lordosis at lower levels of estrogen priming than did systemically administered progesterone. In Exp II, Ss brought into sexual receptivity by administration of estrogen and progesterone received preoptic infusions of an acetylcholine synthesis inhibitor, hemicholinium-3 (HC-3). Significant reductions in the incidence of lordosis were observed following bilateral infusion of HC-3 (1.25 μg/cannula). This inhibition of lordosis was prevented when carbachol (.5 μg/cannula) was infused along with HC-3. Results confirm the importance of cholinergic influences on sexual behavior in female rats. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Hypophysectomy facilitates sexual behavior in female rats

Lordosis was elecited in 49% of 87 hormonally untreated, hypophysectomized-ovariectomized (hypox-ovx) female rats in response to palpation of the flanks and perineum (vaginal stimulation was not applied). By contrast, only 12% of 113 hormonally untreated ovariectomized (ovx) rats showed lordosis in response to such stimulation. Subsequently, hypox-ovx and ovx-only rats were given daily injections of 1 mug/kg estradiol benzoate (EB) and tested for sexual receptivity with males. Teh estrogen-treated hypox-ovx females became sexually receptive significantly earlier, and exhibited higher lordosis quotients and more soliciting behavior, than the estrogen-treated ovx-only rats. The increased sexual responsiveness in the hypox-ovx rats could be due to increased LRH activity. To test this, we treated hypox-ovx rats with dihydrotestosterone propionate (DHT-P), which suppresses plasma LH levels but is relatively ineffective in inducing sexual receptivity, and found a significant depression of lordosis responsiveness. These experiments suggest that hypox-ovx females show a heightened responsiveness to hormonal and/or sensory factors that induce a lordosis response, possibly because of increased LRH activity.     

Effects of repeated testing on sexual behavior of the female rat.

Investigated effects of stimulation during repeated testing, using 24 female Sprague-Dawley rats in which intromission was prevented by a vaginal mask. Ss were ovariectomized and administered 1 mg of estradiol benzoate (EB) daily for 10 days (Exp I) or 5 mg of EB for 2 days (Exp II). Behavioral indices included lordosis quotient (a measure of sexual receptivity) and rejection quotient (a measure of social rejection of the male). Intensity and duration of lordosis gave additional measures. In Exp I hourly testing increased lordosis quotient and duration, especially in Ss receiving EB for 5 days; no effects of daily testing were shown. Exp II compared the behavior of Ss that were either handled hourly and tested hourly with the male rat or only handled hourly to the behavior of Ss that were tested and handled only once. Repeated testing and/or handling facilitated sexual responsiveness, while Ss that received neither treatment were sluggish in their social response to the male rat when they were tested, and were not sexually receptive. (17 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence for involvement of midbrain central gray in cholinergic mediation of female sexual receptivity in rats.

Conducted 3 experiments with 63 female Sherman rats to determine the role of the midbrain central gray (MCG) in facilitation of lordosis by cholinergic agonists. Selected findings show that Ss with MCG damage displayed significantly less facilitation than sham-lesion Ss. Pretreatment with scopolamine (SCOP) abolished lordosis facilitation in both groups, and after treatment with estradiol and progesterone, sham-lesion Ss showed more receptivity than MCG-lesion Ss. Systemic injection of SCOP produced a significant decline in lordosis for both groups. Results suggest that the MCG plays an important role in the cholinergic mediation of female sexual receptivity. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nitric oxide mediates sexual behavior in female rats

Nitric oxide (NO), an active free radical formed during the conversion of arginine to citrulline by the enzyme NO synthase (NOS), mediates vasorelaxation, cytotoxicity, and neurotransmission. Neurons containing NOS (NOergic) are located in the hypothalamus. These NOergic neurons control the release of several hypothalamic peptides. Release of NO from these NOergic neurons stimulates pulsatile release of luteinizing hormone-releasing hormone (LHRH) in vivo and LHRH release in vitro. LHRH not only induces LH release, which induces ovulation, but also facilitates female sexual behavior. Sexual behavior can be induced reliably in estrogen-primed ovariectomized female rats by progesterone (P). This behavior consists of proceptive behavior to attract the male and the assumption of a clear characteristic posture, lordosis, when mounted by the male. To ascertain the role of NO in the control of sexual behavior in female rats, an inhibitor of NOS, NG-monomethyl-L-arginine was microinjected into the third cerebral ventricle (3V) of conscious, ovariectomized, estrogen-primed rats with indwelling cannulae. NG-Monomethyl-L-arginine (10-1000 micrograms) prevented P-facilitated lordosis when administered intracerebroventricularly into the 3V, 20 min prior to the 3V injection of P. NG-Monomethyl-D-arginine, which does not inhibit NOS, did not inhibit lordosis under the same experimental conditions. Microinjection into the 3V of sodium nitroprusside (SNP), which spontaneously releases NO, facilitated lordosis in estrogen-primed rats in the absence of P. The facilitation of lordosis induced by either P or SNP was prevented by intracerebroventricular injection of hemoglobin, which binds NO. Lordosis facilitated by P or SNP was blocked by injection of LHRH antiserum into the 3V. The results are interpreted to mean that the P-facilitated lordosis response is mediated by LHRH release. Furthermore, since NO release from SNP also facilitates lordosis in the absence of P and this response could be blocked by LHRH antiserum, we conclude that P brings about the release of NO, which stimulates LHRH release that facilitates lordosis. Thus, the results indicate that NO induces LHRH release and that LHRH then plays a crucial role in mediation of sexual behavior in the female rats.     

Hippocampal and cortical activity during sexual behavior in the female rat.

Studied hippocampal and cortical activity during sexual behavior in 6 female albino van Leeuwenhoek-Huis R-strain rats. Hippocampal theta appeared during S's soliciting behavior. High-frequency theta accompanying the male's pursuit slowed when the male mounted the female and then increased in frequency during the brief continuation of lordosis following mounts without vaginal penetration. During prolonged lordosis after intromissions and ejaculations, slow theta continued. No changes in cortical frequencies were observed during mounts, intromissions, or ejaculations. During immobility (standing, sitting, and lying down), hippocampal activity became slow and irregular. High-amplitude hippocampal and, eventually, cortical spindles developed during immobility as sexual exhaustion was approached. Immobility and its accompanying EEG spindling are interpreted as indicative of a sexual satiety or inhibitory process. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Arbitration, mediation, and sexual harassment.

The 1998 Supreme Court decisions in Faragher v. City of Boca Raton and Burlington Industries, Inc. v. Ellerth recognized an affirmative defense to hostile environment sexual harassment claims based in part on the existence of an effective policy prohibiting sexual harassment in the workplace. The promulgation or refinement of policies prohibiting sexual harassment will likely lead to an increase in complaints of sexual harassment. This article concludes that mediation and arbitration procedures which follow recognized standards of due process are appropriate means to resolve these claims and may substantially contribute to the Title VII goal of eradicating discrimination from the workplace. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differential influence of stereoisomers of estradiol on sexual behavior of female hamsters.

Morphological and behavioral responses to estradiol-17β (E?-17β) and estradiol-17α (E?-17α) were examined in a series of 3 experiments with golden hamsters. The E?-17β augmented uterine growth to a greater extent than E?-17α. Lordosis in ovariectomized adults was elicited by treatment with E?-17β but not with E?-17α (each tested in combination with progesterone). When administered neonatally, only E?-17β disrupted estrous cyclicity in the intact female and induced the ability to mount in ovariectomized, androgen-treated adults. Results suggest the existence of a stereospecific response to estrogenic stimulation in neural tissue comparable with that occurring in the uterus. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Central progesterone induces female sexual behavior in estrogen-primed intact male rats.

Injection of progesterone induced high levels of female lordotic behavior in 10 of 47 intact, estrogen-primed male Sprague-Dawley rats when it was applied directly to the medial preoptic/anterior hypothalamic area. All 17 Ss previously had shown lordosis when the serotonergic antagonist methysergide was applied to the same central sites. Few Ss responded to systematic progesterone and none to intracranial cholesterol. Intradiencephalic Metycaine, a local anesthetic, induced lordosis in 8 Ss that previously had responded to central progesterone. These data indicate that estrogen and progesterone act synergistically to induce lordosis in male rats when progesterone is administered directly to sensitive brain sites. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effects of testosterone propionate administered perinatally on sexual behavior of female ferrets.

Conducted an experiment with 25 female and 8 male albino ferrets ( Mustela furo ). Females that received injections of testosterone propionate (TP) early in postnatal life displayed significantly more masculine behavior than did control females when gonadectomized and administered either TP or estradiol benzoate in adulthood. This increased masculine response potential was not correlated with the effects of early TP treatment on phallic development. In contrast to results obtained in most other species, perinatal administration of TP to females failed to disrupt their ability to display the behavior that is characteristic of the sexually receptive animal in estrus. When estrogenic stimulation was provided in adulthood, the receptive behavior of 3 groups of perinatally androgenized females was indistinguishable from that of both male and female controls. However, after gonadectomy and administration of TP, control males and females that had received TP prenatally plus on Day 3 were significantly more receptive than were control females. The induction of receptivity by TP was significantly inhibited by simultaneous administration of the antiestrogen MER-25. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mesencephalic participation in the control of sexual behavior in the female rat.

In 2 experiments with 78 female albino rats, electric stimuli applied to both pudendal nerves evoked field potentials, unit responses, and multiunit responses in the ventrolateral midbrain, in and around the peripeduncular nucleus. Bilateral lesions placed in this region suppressed sexual behavioral responses (lordosis and courting behavior) of ovariectomized Ss primed with 5, 10, 100, and 1,000 μg of estradiol benzoate and 2 mg/kg progesterone. It is proposed that the region in question represents a relay station for the integration of sensory and endocrine information concerned in the control of receptive sexual behavior in the female rat. (54 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Consequences of perinatal hormone manipulation on the adult sexual behavior of female rats.

Compared male and female behavior of 46 female Sprague-Dawley albino rats treated with prenatal or prolonged postnatal testosterone propionate (TP) or cyproterone acetate (Cyp A), an antiandrogen, to 13 control females. Prenatal TP decreased quality and rate of lordotic responding while increasing incomplete and complete male copulatory rate. Postnatal TP also impaired female behavior but increased only complete male copulations. Results suggest that, in the rat, gonadal steroid levels present during prenatal as well as postnatal developmental stages determine the direction and degree of differentiation of adult sexual behavior. Prenatal Cyp A had no effect on female behavior or external genitalia but decreased both types of male copulatory responses, suggesting that male behavior in normal females is based on prenatal androgenic modification of the nervous system. (30 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the association between sexual attraction and adolescent risk behavior involvement: Examining mediation and moderation.

On the basis of a large-scale survey of high-school youth, the authors compared adolescents reporting exclusively heterosexual, mostly heterosexual, bisexual, and predominately same-sex attraction based on high-risk involvement across a range of risk behaviors. Bisexual and same-sex attracted groups were characterized by heightened high-risk involvement relative to the other two groups. Mediation analysis was used to determine whether these group disparities were explained by a set of normative predictive factors spanning multiple life domains. Differences among a combined exclusively/mostly heterosexual attraction group and both the bisexual and same-sex attraction groups were attenuated (66% and 50%, respectively) after incorporating the hypothesized intervening predictive factors, providing evidence of partial mediation. Primary mediators included intrapersonal (attitudes toward risk-taking; academic orientation), interpersonal (peer victimization; parental relationships; unstructured activities), and environmental (substance availability) factors. Mediation results were consistent across participant age and sex. Implications, limitations, and directions for future research are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adolescent sexual behavior.

What is known about adolescent sexual behavior is reviewed. First, the onset of sexual behavior in the teenage years is considered as a function of cohort, gender, and ethnic differences. Omissions in the research on sexual behavior other than intercourse are highlighted. Possible biological, social, and social cognitive processes underlying teenage sexual behavior are then considered. Next, demographic trends in the use of contraceptives and antecedents of regular birth control use are reviewed. Finally, some of the successful program initiatives directed toward altering sexual and contraceptive practices are discussed, keeping in mind the importance and relative lack of well-designed and carefully evaluated programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Prospective sexual behavior.

Discusses W. B. Miller's (see record 1984-17604-001) use of the term "proceptive" in his analysis of reproductive freedom. It is argued that the continuum from contraceptive to proceptive forms only one part of the complex spectrum of human sexual behavior and that, because much of modern human sexuality deliberately avoids conception and reproduction, it is essential to consider the continuum from "conceptive" to "extraceptive" as well. It is suggested that most people will probably exercise some degree of proceptive sex choice as to their offspring when that choice does not require surgical procedures like amniocentesis and when the effectuation does not demand abortion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Decline of sexual behavior in castrated male rats: effects of female precopulatory behavior

Ventricle cells from neonatal rats were cultured in a medium preventing cell proliferation on a modified Roller apparatus with a defined pericellular oxygen partial pressure (pO2) of 38 or 0.6 mm Hg for about one week. The cells were harvested after the second and eighth day of culture (corresponding to one or seven days of culture under a defined pO2) and prepared for electron microscopy. Electron micrographs of this material were examined by stereologic techniques. The obtained results showed some deviations of mitochondrial fine structure of heart muscle cells depending on oxygen supply. During cultivation with a pO2 of 0.6 mm Hg (hypoxic conditions) we observed a proportional increase in mitochondria without cristae and an increase in size accompanied by a more irregular shape. On the contrary, the mitochondria of cells cultured with a pericellular pO2 of 28 mm Hg, which we consider to be a normoxic condition, did not show any deviation of inner membrane arrangement, but an increase in number and a decrease of size during cultivation was apparent. The mitochondria-myofibrils ratio decreased during cultivation in both conditions of oxygen supply. The ratio between sarcoplasmatic reticulum and myofibrils decreased markedly at a pO2 of 0.6 mm Hg.     

Neonatal androgenic stimulation and adult sexual behavior in male and female golden hamsters.

In an experiment with 48 male and 48 female golden hamsters, neonatally and adult castrated males as well as neonatally androgenized and nonandrogenized females were tested for both mounting and lordosis behaviors during treatment with either testosterone or ovarian hormones. Neonatal androgenization facilitated mounting behavior in adult Ss administered either testosterone or ovarian hormones and suppressed lordosis behavior in adult ovarian-hormone-treated Ss. Early androgen effects on the display of lordosis behavior during adult testosterone treatment were complex and varied with the exact timing of perinatal endogenous or exogenous androgenization. Species differences in hormone-behavior relationships and the possible role of perinatal androgenization in the development of rodents' ability to aromatize androgens are discussed. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)