Sensation seeking and hormones in men and women: exploring the link.

Risky behaviors (e.g., binge drinking, drunk driving, risky sex) are increasing among U.S. college students, and the personality trait of sensation seeking provides a potential link between such norm-breaking behaviors and biological processes. We examined the relationship between sensation-seeking behaviors and two hormones, testosterone and cortisol, in male and female college students. Hormone levels were hypothesized to contribute to the variability of individual scores on Zuckerman's Sensation-Seeking Scale. As expected, males scored higher on the scale than females, but the data failed to support the generally accepted positive relationship between testosterone and sensation seeking for either sex. Instead, our results support the existence of a significant inverse relationship between cortisol and sensation seeking in men, but not in women, even after adjustment for testosterone levels and age. Our study contributes to the current literature by (a) supporting the association between risky behavior and a hormone other than testosterone, (b) being the first to examine the association between cortisol and sensation seeking in women, and (c) identifying a possible effect of gender on the association between hormones and sensation-seeking behaviors. Gendered social norms and expectations are likely to be partly responsible for this effect. Theory-guided interdisciplinary research is needed to improve understanding of the biological influences on human behavior, and special attention must be paid to social context, women's perceptions of their expected behavior, and gendered socialization regarding norm-breaking or risky behaviors, which may obscure biological links to female behavior.

Substance use among women at risk for HIV infection.

This article reports results from a survey of culturally diverse women at risk for HIV infection in south Florida. Data concerning their substance use and its association with HIV risk behaviors are presented. Results indicate levels of consumption which exceed expectations based on general estimates of female substance use. Further, substance use was associated with specific behaviors and lifestyles which placed the women at increased risk for HIV infection.

Effects of maternal stress on puberty, fertility and aggressive behavior of female mice from different intrauterine positions.

We examined the effects of maternal stress (bright light and heat) during the last third of pregnancy on subsequent reproductive and behavioral characteristics of female mice from different intrauterine positions. Female mice that develop in utero between two male fetuses (2M females) differ from females that develop between two female fetuses (0M females) in their serum concentrations of both testosterone and estradiol during the fetal period of sexual differentiation. After birth, 0M and 2M females differ in a wide range of reproductive characteristics. We examined the effects of maternal stress on the response to social cues regulating the timing of first vaginal estrus and the length of the first postpubertal estrous cycle when 4 0M or 4 2M females were housed together next to an adult male. Maternal stress decreased the inhibitory effect of being housed with other females in terms of the length of the first postpubertal estrous cycle, but this only occurred in 0M females. We found no effect of maternal stress or intrauterine position on the capacity to mate and remain pregnant, regardless of whether 0M or 2M females were stressed or not stressed during early pregnancy prior to implantation. While there was no effect of prior intrauterine position on interfemale aggression or behavior toward young, maternal stress did tend to reduce the likelihood that females (in diestrus) would exhibit aggression toward other females.

AIDS knowledge and risk behaviors among culturally diverse women.

This article reports results from a survey of women at risk for HIV infection. The sample (n = 620) included black (50.6%), white (28.7%), Hispanic (13.4%), and Haitian (5.0%) adult women from south Florida. Data concerning their AIDS knowledge, prevalence of risk behaviors, and perceived vulnerability are presented. Results indicate differences in certain knowledge areas and risk behaviors by race/ethnicity and a consistent incidence of unprotected sex with their main partners across all racial/ethnic groups.

PIP: Florida has the 3rd highest cumulative number of AIDs cases among states in the US, and 12% in Florida are women, which is 3% higher than the national average. The study describes the AIDs knowledge and sexual behavior of women at high risk of HIV infection in 1989 from Dade and Broward counties in Florida. As part of a 3-year project, it was designed to develop a cross sectional description of women at risk, and to develop and evaluate interventions aimed at perinatal AIDs prevention. 620 nonpregnant women were recruited from county jails and detention centers (59.3%), county health, STD, and family planning clinics (26%), alcohol/drug treatment centers (13.6%), and other (1.1%). The mean age of respondents was 28.9 years. 51% were never married, and 76% had 1-3 children. 45% were unemployed. 21% reported income from prostitution and 17% from illegal activity. 44% had ever engaged in prostitution. 83% had used an illegal substance of which 22% was IV drugs. 8.7% were seropositive. 71% received AIDs, STDs, contraception, and sexuality information from the mass media, and 59% from medical professionals and public health clinics. The limitations were the representatives of the sample, and the validity and reliability of the questionnaire. The results of AIDs knowledge, risk behavior, and vulnerability revealed that the majority were well informed about AIDs and HIV infection, with the exception of Haitians. The findings support treating Haitian women as a special population for AIDs prevention programs. Those 20 and 41 years tended to believe myths about AIDs and casual contact and perceived risk based on the appearance of an individual. 75% were unaware of bleach as a remedy for dirty needles. As a subcultural influence, people need more knowledge about safer drug use. Knowledge did not influence risky behavior. Transmission appears to be from heterosexual contact. A greater prevalence of sexual risk behavior was reported with main partners even though 75% agreed one couldn't trust lovers in reporting STDs. Program focus on prostitutes may have limited impact. Hispanics reported the greatest prevalence of risk behaviors, followed by whites, blacks, and Haitians. Over 40% of Hispanic and Haitian and 20% of black women reported intention to not use a condom with a seropositive partner. Economics and gender role norms are a great influence. There was a general lack of perceived vulnerability. Successful community and society level strategies involve continued education, sociocultural sensitivity, gender role issues, sexual decision making, and economic factors.

Paradoxical effects of maternal stress on fetal steroids and postnatal reproductive traits in female mice from different intrauterine positions.

We examined effects of maternal stress on prenatal serum concentrations of testosterone and estradiol and on postnatal reproductive traits in female mice from different intrauterine positions. On Day 18 of fetal life, control females positioned in utero between two male fetuses (2M females) had higher concentrations of testosterone and lower concentrations of estradiol in serum than control female fetuses located between two females (0M females). Control females positioned between a male and a female fetus (1M females) had intermediate levels of both hormones. Prior intrauterine position in control females accounted for differences in genital morphology (length of the anogenital separation) at birth and length of estrous cycles during adulthood. Maternal stress eliminated these postnatal differences due to prior intrauterine position: all 0M, 1M, and 2M female offspring of stressed mothers exhibited postnatal traits that were indistinguishable from those of control 2M females. Maternal stress resulted in an increase of over 1 ng/ml in serum testosterone in all female fetuses; the magnitude of the increase was similar for 0M, 1M, and 2M females. There was no effect of maternal stress on serum concentrations of estradiol in 0M and 2M female fetuses. Maternal stress resulted in a dramatic change in the postnatal traits of 0M females, whereas 2M females showed no change. Since the effect of maternal stress on sex steroids was similar among fetuses from different intrauterine positions but postnatal response to maternal stress varied by intrauterine position, other components of the endocrine system may mediate effects of maternal stress on these postnatal characteristics.

Lesions in the preoptic area suppressed sexual receptivity in ovariectomized rats with estrogen implants in the ventromedial hypothalamus.

The objective of the experiment was to determine if electrolytic ablation of a portion of the preoptic area (POA) influenced the activation of female lordosis behavior by implants of estradiol benzoate in the ventromedial hypothalamus (VMH) of ovariectomized (OVX) rats. Two weeks after ovariectomy, rats received either bilateral electrolytic lesions (2 mA for 10 sec in Experiment 1, or 1 mA for 5 sec in Experiment 2) in the POA, or sham lesions (all procedures except passage of current). On the same day (day 0 of the experiment) thirty-gauge stainless steel cannulae containing crystalline estradiol benzoate were stereotaxically placed bilaterally into the VMH of all the rats. Subsequently, females were tested for the lordosis response to stud males on days 2, 4, 6, 8, and 10 in Experiment 1 or on days 7, 14 and 15 in Experiment 2. All rats received 0.5 mg progesterone (SC) only before the last test. A female was considered sexually receptive if she exhibited a lordosis quotient (LQ) greater than or equal to 10 (LQ = No. lordosis responses/10 mounts by male X 100). The frequencies for sexual receptivity in females with POA lesions were significantly lower than those for control females without lesions in both experiments. Additionally the degree of receptivity (lordosis quotient) was significantly lower on each test day for rats with POA lesions than that for rats without POA lesions. The results imply that the maintenance of the integrity of the POA under this experimental condition was important for the expression of the facilitative influence of the VMH on lordotic responsiveness.

The effects of intrauterine position on competition and behavior in the mouse.

The purpose of the present study was to examine the effect of intrauterine position on: (1) competition for limited food resources when the animals were previously deprived of food; (2) social preference for a male during various phases of the estrous cycle; and (3) social and sexual behavior when the animals were provided with like-treated females or receptive females, respectively. Females developing in utero between two males (2M females) and females developing between two females (0M females) were different on only one measure recorded during the competition for limited food, i.e., gaining control of the food pellet, with the 0M females outcompetiting the 2M females. When given a choice between a male or a female neither 2M or 0M females in estrus showed a preference for the male. The results also indicated that 2M females were significantly more aggressive and more likely to show male sexual behavior when compared to 0M females.

Postpartum moods in men and women.

Twenty-one married couples, recruited from childbirth classes (mean age 29.6 years), were administered questionnaires measuring 20 different moods during the third trimester of pregnancy (prepartum period), during the postpartum period, and at 6 months after birth (follow-up period). In each questionnaire period individual questionnaires were filled out daily by both the mother and father for 10 consecutive days. The results indicated that the postpartum period, compared with the prepartum and follow-up periods, is an emotionally unique time but not a period marked by depression. The moods that were rated as being experienced more strongly by men and women during the postpartum period were associated with anxiety and concern for one's ability to cope such as "nervousness," "worried," "helpless," and "anxious" or positive emotions such as "enthusiastic" and "happy." It is concluded that men and women in this sample tend to experience the postpartum period in an emotionally similar way.

Suppression of sexual behavior and localization of [3H] puromycin after intracranial injection in the rat.

Bilateral intracranial injections of puromycin (10 micrograms/0.5 microliter vehicle) into the preoptic area (POA) of steroid-primed ovariectomized rats resulted in a significant decrease in the lordosis response when compared to saline treated controls. To determine the extent of puromycin diffusion after intracranial injection, [3H] puromycin was injected into the right POA of ovariectomized rats. Neural regions anterior, posterior and superior to the POA, and the right and left POA were assessed for tritium activity 0.5, 6 and 24 hours after stereotaxic surgery. The activity was primarily located at the injection site or in the injection tract. The highest amount of activity external to the injection site or injection tract was found in the right ventromedial hypothalamus.

Brain catecholamine content during the estrous cycle and in steroid-primed rats.

Norepinephrine (NE) and dopamine (DA) levels were measured in several estrogen concentrating brain regions over the estrous cycle and in steroid-primed ovariectomized rats under experimental conditions used to study sexual receptivity. Norepinephrine content in the ventromedial hypothalamus (VMH), lateral septum (LS) and medial preoptic area (POA) varied during the estrous cycle. The highest NE levels were found during metestrus in these brain regions. In the ovariectomized rat, NE levels were increased in the POA and LS 12 hours (hr) after the injection of 3 micrograms of estradiol benzoate (65% and 33%, respectively). Norepinephrine content in the POA and LS remained elevated 24 hr and 48 hr (0.5 mg progesterone at 42 hr) after treatment but were not different from control levels at 96 hr. Dopamine concentrations were not significantly altered over the estrous cycle or by the administration of estradiol benzoate in any of the brain regions studied. These results suggest that estrogen may selectively alter noradrenergic activity in brain regions that are implicated in the control of sexual receptivity and/or ovulation.

Cycloheximide activation of the lordotic response in low-dose, estrogen-treated ovariectomized rats: evidence for modulating inhibitory influences of the limbic system on sexual behavior.

This study tested the effect on intracranially injected cycloheximide (CHX), an inhibitor of protein synthesis, on facilitation of sexual receptivity in ovariectomized rats. The rats received 0.5 microgram estradiol benzoate (EB), s.c. once daily on days 8 through 12 after ovariectomy (OVX). Either CHX (in 0.5 microliter saline) or 0.5 microliter saline was injected into the lateral septum (LS), cortical nucleus (ACO) or medial nucleus of the amygdala or medial preoptic area on day 11 after OVX. The dose of EB was insufficient to facilitate lordotic behavior on day 10 or day 12 after OVX unless CHX was injected into the LS or ACO. Injection of saline did not influence lordosis.

Hypothalamic injection of cycloheximide in the 4-day cyclic rat. Acute suppression of lordotic behavior and ovulation.

The results of serveral studies imply that estrogen can act upon the central nervous system via a protein synthetic step. Our objective was to determine if the intrahypothalamic (preoptic area, POA) injection of cycloheximide (CHX), an inhibitor of protein synthesis, at 17.00 h on diestrus II of the 4-day cycle altered lordotic behavior and (or) ovulation in the intact rat (sexual receptivity to males normally begins on the evening of proestrus as herein defined; ovulation occurs on estrus of the cycle). CHX-treated females were tested for lordotic behavior at 23.00 h on proestrus, then killed at 17.00 h on the following day. None of the CHX-POA rats were receptive to the males and 90% of these rats did not ovulate. Thus, CHX significantly suppressed sex behavior and ovulation in the cyclic rat.

Intracranial cycloheximide: effect on male mouse sexual behavior and plasma testosterone.

Cycloheximide (Cyclo), an inhibitor of protein synthesis, infused bilaterally into the preoptic area (POA) of intact B6D2F male mice significantly inhibited male sexual behavior when the males were presented with receptive females 12 hr after treatment. The few males that ejaculated appeared to copulate normally. This finding suggests that Cyclo acts primarily by inhibiting sexual arousal rather than sexual performance. The inhibition of sexual behavior was not observed when the males were tested 84 hr after treatment. After exposure to an estrous female, plasma testosterone levels were measured in males with POA infusions of Cyclo or saline vehicle. No significant difference was found, but both groups had significantly higher levels of plasma testosterone than males not exposed to estrous females. It is suggested that the interference with sexual behavior by Cyclo was not due to interference with the neuroendocrine mechanisms controlling blood andorgen levels, but due to Cyclo acting directly on the neural circuits controlling sexual responsiveness.

Influence of neonatal castration or neonatal anti-gonadotropin treatment on fertility, phallus development, and male sexual behavior in the mouse.

Male mice were castrated on the day of birth or were treated with anti-gonadotropin serum (AGS) successively on days 1, 3, and 5 of age. When the adult AGS-treated males were compared with normal rabbit serum (NRS)-treated males with respect to fertility, male sexual behavior, gonadotropin release, body size, and penis size it was found that: (1) fertility of AGS-treated males did not differ from that of NRS-treated males; (2) AGS-treated males showed a significant reduction in penis size, compared with NRS-treated males; (3) both groups showed high levels of male sexual behavior; (4) neither group showed the capacity to support ovulation in ovarian grafts from immature mice. It was also observed that the fertility of female mice treated with AGS on days 1, 3, and 5 of age did not differ from that of control females treated with comparable doses of NRS. Male mice castrated at birth showed a significant reduction in male sexual behavior and penis size compared with males first sham-operated at birth then castrated at 25 days of age. Thus, males castrated at birth were similar to males receiving AGS in infancy, except for sex behavior. The results suggest that the neonatal pituitary in the mouse may not have an important role in the process of sexual differentiation. Previous data for the male rat were compared with those for the mouse.