Endocrine, psychological and genital response to sexual arousal in men.

The endocrine, genital, and cognitive--affective responses of sexually functional men were compared under sexually arousing and non-arousing conditions. Sexually aroused subjects showed significantly higher serum luteinizing hormone concentrations than non-aroused subjects. Testosterone concentration was correlated with higher levels of penile response, but it did not prime further sexual arousal. Cortisol and prolactin concentrations decreased in both groups, more in the non-aroused group, and appeared to both inhibit and facilitate sexual response, depending on the level of anxiety reported by the subjects. Cortisol was correlated with self-reported worry, and testosterone with relaxation. These results support a multidimensional approach to the endocrine study of sexual arousal that includes both cognitive and genital response components.

Individual differences in mood in early childhood: their relation to gender and neonatal sex steroids.

Predominant mood states were assessed for 104 children via 24-hr mother diaries during the first 2 years of life. Consistent sex differences were found across ages and across cohorts: boys were more often reported to be in a happy/excited mood, girls in a quiet/calm mood. The sexes did not differ in the frequency of negative moods (including crying), however. Scores for happy/excited and quiet/calm mood states were quite stable across the ages sampled: 6, 9, 12, 18, and 26 months. These stabilities were generally greater for boys. Negative moods showed only borderline stability. Relationships between the mood scores and five sex-steroid hormones (progesterone, androstenedione, testosterone, estrone, and estradiol), assayed from umbilical cord blood at the time of the children's birth, were assessed. For boys small, but significant, positive relationships were found between happy/excited moods and androstenedione, estrone, and progesterone. Correlations of opposite sign were found between these hormones and boys' scores for quiet/calm mood. For girls, the correlations were low and insignificant, but generally of opposite sign from those found for boys, and a number of hormones showed significant sex-by-hormone interactions in their relation to children's mood scores. The implication of these findings for the understanding of sex differences is discussed. Also discussed are the problems of interpretation posed by the intercorrelations among hormones when hormone scores are used for prediction of aspects of later development.

Methyltrienolone (R1881) is not aromatized by placental microsomes or rat hypothalamic homogenates.

The in vitro conversion of the synthetic steroidal androgen methyltrienolone (17 beta-hydroxy-17 alpha- methylestra -4,9,11-trien-3-one) to an estrogen was investigated. First, with a placental microsome preparation a 10-fold molar excess of methyltrienolone did not affect the aromatization of testosterone. Therefore, methyltrienolone did not compete with testosterone in this very active aromatase system, nor did it inhibit the aromatization. Second, while the placental aromatase very efficiently converted testosterone to estrogens, it did not convert methyltrienolone [3H] to estrogenic (phenolic) products. Third, homogenates of rat hypothalamic tissue were also unable to aromatize methyltrienolone, although they converted small quantities of testosterone to estradiol and 19-hydroxyandrostenedione to estrone. This lack of aromatization of methyltrienolone is consistent with observations of additional behavioral and in vivo biochemical experiments.

Neonatal sex-steroid hormones and muscular strength of boys and girls in the first three years.

Five sex-steroid hormones were assayed in umbilical cord blood. Strength was assessed in children in three samples at several ages from birth to 33 months. At different ages, different strength measures were taken, viz., at birth, prone head responses; at 3 months, leg strength; from 6 to 33 months, grip strength. Boys had higher average strength scores than girls but the sex differences were small and did not increase or decrease over the age period studied. Across-age strength scores showed a significant relation to androstenedione and a significant interaction of sex and progesterone. Both boys and girls with higher strength scores had lower androstenedione. Girls with high cord blood progesterone showed low strength while boys with high progesterone showed high strength. There were no sex differences in androstenedione or progesterone level. The androstenedione finding did not replicate across samples but the Progesterone X Sex interaction was replicated in all three samples. No relationship was found between strength and other hormones assayed: testosterone, estradiol, and estrone.

Neonatal sex-steroid hormones and timidity in 6-18-month-old boys and girls.

Five sex-steroid hormones (testosterone, androstenedione, estradiol, estrone, and progesterone) are assayed in umbilical cord blood. Timidity is assessed in home and laboratory observations by reactions to a range of novel toys in children from 6 to 18 months of age. Significant short- (1 week) and long- (several months) term stability in timidity is demonstrated. Girls have higher mean scores on observed timidity than do boys in 2 of the 3 samples tested. An across-age timidity score is computed which shows significant correlations with neonatal progesterone, testosterone, and estradiol for boys, but is not significantly predicted by hormone concentrations in girls.

5 alpha-androstane-3 beta, 17 beta-diol binds to androgen and estrogen receptors without activating copulatory behavior in female rats.

The ability of the androgen metabolite 5 alpha-androstane-3 beta, 17 beta-diol (3 beta-A-diol) to facilitate copulatory behavior was assessed directly in adult ovariectomized rats. Neither the highest dosage of 5 mg/day for three days, nor 2 mg/day for 15 days could induce lordosis behavior in females that displayed typically high lordosis quotients with low dosages of estradiol (E). Furthermore, prolonged administration of 5 alpha-dihydrotestosterone (DHT) induced a low but significant level of male-typical mounting behavior in females, whereas 3 beta-a-diol administered for 20 days (2 mg/day) had no effect on mounting behavior. However, this reduced androgen metabolite did compete moderately well for DHT and E binding sites on androgen and estrogen receptors respectively in hypothalamic cytosol preparations. We conclude that in spite of its ability to bind to these receptors in the brain 3 beta-A-diol, a major metabolite of DHT, is totally inert with respect to sexual behavior.

Hormonal and behavioral response of male chimpanzees to a long-acting analogue of gonadotropin-releasing hormone.

A long-acting preparation of gonadotropin-releasing hormone (GnRH) was administered to three adult male chimpanzees living in a socially integrated group. Hormonal changes and behavioral responses were monitored for 8 days. Blood serum levels of luteinizing hormone peaked at about 8 hr and returned to baseline at 48 hr. Total serum testosterone reached the highest levels of 140% above baseline at 24 hr and returned to baseline after 48 hr. Out of a wide variety of behaviors observed in detail, only one cluster of three related behaviors showed even a suggestion of response: The two measures of activity, lone travel (p < 0.05) and distance traveled (p < 0.1), decreased on the day of hormone administration followed by an increase on the 2 subsequent days, and idle time (p < 0.1) revealed the reciprocal pattern. In view of various reports of behavioral effects of GnRH in other species, it is particularly noteworthly that parameters of sexual and agonistic behavior of male chimpanzees definitely did not change.

Concentrations of sex hormones in umbilical-cord blood: their relation to sex and birth order of infants.

In 3 groups of human newborns, 5 sex hormones were assayed from samples of umbilical-cord blood, and concentrations were analyzed by the sex and birth order of the infants. The 5 hormones assayed were testosterone, androstenedione, estrone, estradiol, and progesterone. Concentrations of testosterone were significantly greater in males than females. The other 4 hormones did not differ significantly by sex. In both sexes, firstborns had significantly more progesterone and estrogens, with progesterone showing the largest birth-order effects. Among male infants, firstborns had higher concentrations of testosterone. The higher concentrations of progesterone in firstborns of both sexes, and of testosterone in firstborn boys, were found not to be due to length of labor, birth weight, or maternal age. However, they were a function of temporal spacing of childbirths. Later borns who were closely spaced in relation to their next-older siblings had lower concentrations of hormones. The effect of temporal separation was greater on male than female infants for each of the 5 hormones studied. The results are discussed in terms of the possible effects of hormone "depletion" on the psychological development of closely spaced later borns.

A study of the effects of gonadotropin-releasing hormone on human mood and behavior.

Gonadotropin-releasing hormone in doses up to 500 microgram was administered to 12 healthy male volunteers. Luteinizing hormone and testosterone levels increased subsequent to GnRH administration. No immediate effects of GnRH on mood and behavior were noted, though an increase in alertness, a decrease in anxiety and fatigue, and an increased speed of performance on automatized motor tasks were noted several hours after GnRH administration.

Orgasmic frequency and plasma testosterone levels in normal human males.

Twenty males participated in a 2-month study examining the relationship between 8 a.m. plasma testosterone levels and orgasmic frequency. Within subjects, higher levels of testosterone are associated with periods of sexual activity. Over subjects, however, the direction of the relationship is reversed. Mean testosterone levels were higher for sexually less active individuals.

Negative affect and plasma testosterone: a longitudinal human study.

The association between mood and plasma testosterone was investigated. Every second day for 2 months, a Multiple Affect Adjective Checklist was filled out by 20 young men. Blood samples taken at the same time were analyzed for testosterone concentration. Relationships between hostility, anxiety, and depression and plasma testosterone levels were tested both within and across individuals. Intrasubject correlation coefficients between affects and hormone were fairly evenly distributed between positive and negative values, some significant on either side. Intersubject correlation coefficients were all positivie. Between depression and testosterone, the correlation was significant only at the 10% level; between the other two affects and testosterone, the correlations were not significant.

A cycle of plasma testosterone in the human male.

The object of the study was to assess the lability of testosterone levels in plasma of normal human males over a long period of time and to search for periodicities in changing levels. Blood samples obtained from 20 healthy young men every second day for 2 months were assayed for total testosterone concentration by radioligand saturation analysis with late-pregnancy plasma. The flucturations of plasma testosterone levels over the total time span were substantial for most individuals; the coefficients of variation ranged from 14 to 42% (median 21%). The presence of periodic functions in these fluctuations was tested by 4 different, relatively independent methods. Close agreement among at least 3 analytic methods was found for 12 out of the 20 subjects. These 12 subjects had cycles of plasma testosterone levels with periods ranging between 8-30 days, with a cluster of periods around 20-22 days. The majority of such cycles were significant at least at the 5% level. The mean amplitudes of these cycles ranged from 9 to 28% of the subjects' mean testosterone levels (average 17%).

Genetic variation of cholesterol ester content in mouse adrenals.

Total cholesterol concentrations in muscle, liver, and plasma do not differ significantly between adult male C57BL/10J and DBA/2J mice. In the adrenal glands of these two strains, of their hybrids, and of AC mice, concentrations of free cholesterol vary by 5 percent. Adrenals from C57 mice, however, contain six times as much esterified cholesterol as adrenals from AC or DBA mice. The intermediate concentrations of cholesterol esters in F(1) hybrids suggest that the difference in this measure is inherited additively. The finding of variation in adrenal cholesterol within a species is useful for the further study of the role of cholesterol in steroidogenesis by means of genetic analysis.