An examination of the characteristics, concentration and distribution of androgen receptor in rat testis during sexual maturation

Previously reported androgen receptor concentrations in rat testis and testicular cell types have varied widely. In the studies reported here a nuclear exchange assay was established in rat testis in which exchange after 86 hours at 4$\sp\circ$C was greater than 85% complete and receptor was stable. Receptor concentration per DNA measured by exchange declined between 15 and 25 days of age in the rat testis, then increased 4-fold during sexual maturation. Proliferation of germ cells which had low receptor concentration appeared to account for the early decline in testicular receptor concentration, whereas increase in receptor number per Sertoli cell between 25 and 35 days of age contributed to the later increase. Increase in Leydig cell number during maturation appeared to account for the remainder of the increase due to the high receptor concentration in these cells. Detailed studies showed that other possible explanations for changes in receptor number (e.g. shifts in receptor concentration between the cytosol and nuclear subcellular compartments or changes in the affinity of the receptor for its ligands) were not likely.^ Androgen receptor dynamics in testicular cells showed rapid, specific uptake of ($\sp3$H) -testosterone that was easily blocked by unlabeled testosterone (RA of 7 nM in both cell types), and medroxyprogesterone acetate (RA of 28 and 16 nM in Sertoli and peritubular cells, respectively), but not as well by the anti-androgens cyproterone acetate (RA of 116 and 68 nM) and hydroxyflutamide (RA of 300 and 180 nM). The affinity of the receptor for the ligand dimethylnortestosterone was similar in the two cell types (K$\rm\sb{d}$ values of 0.78 and 0.71 nM for Sertoli and peritubular cells) and was virtually identical with the affinity of the whole testis receptor (0.89 nM). Medroxyprogesterone acetate and testosterone significantly increased nuclear androgen receptor concentration relative to untreated controls in Sertoli and peritubular cells, whereas hydroxyflutamide and cyproterone acetate did not. Despite the different embryological origins of peritubular and Sertoli cells, their responses to both androgens and anti-androgens were similar. In addition, these studies suggest that peritubular cells are as likely as Sertoli cells to be primary androgen targets. ^

Is sexual intimacy among older adults positively associated with mental well-being?

Background. The elderly population aged 60 and above is increasing rapidly throughout the world. The aging process affects physical health of individuals, which in turn affects sexuality and sexual activity. However, many elderly adults continue to engage in one or more forms of sexual activities well into their 70s, 80s, and even in 90s. Despite the widespread stereotypes, misconceptions, and negative attitudes surrounding sexuality in elderly adults, it has been found to be an important aspect of the health of the elderly. However, association between the frequency of sexual activity and mental well being among older adults has not been documented in the literature. ^ Methods. To test the hypotheses that mental well being indicators such as depression, anxiety, and stress were inversely associated with greater frequency of sexual intimacy, a secondary data analysis was conducted using the National Social Life Health and Aging Project (NSHAP) using multivariate logistic regression. The NSHAP was a population-based study that was conducted on a national scale including 1455 men and 1550 women aged 57-85.^ Results. Approximately 1430 (54.1%) of the total population reported being sexually intimate in the past 12 months whereas 1481 (45.9%) participants reported that they did not perform any sexual activity in the past 12 months. In addition, approximately 895(31.1%) participants reported engaging in sexual activity ≥ 2-3 times per month with 665 (78.9%) of these participants reported performing vaginal intercourse only, 14(2.0%) oral sex only, and 89(10.5%) reported performing both vaginal intercourse and oral sex. Controlling for socio-demographic characteristics, frequently (≥2-3 times per month) sexually active participants showed lower odds ratio of depression (OR= 0.60; 95%CI = 0.46, 0.78), anxiety (OR= 0.67; 95% CI= 0.53, 0.86), and stress (OR=0.73; 95% CI = 0.6, 0.88) compared to those who had less frequent sexual activity or who had no sexual activity in the past 12 months.^ Conclusion. Lower levels of depression, anxiety, and stress appear to be associated with greater frequency of sexual activity. Public health interventions should focus on educating elderly adults about their sexual health and how to seek medical help for their sexual problems. Public health professionals should also be educated on how to best assess sexual needs of the elderly adults.^

Changes in sexual behaviors associated with crack cocaine cessation among African Americans in Houston, Texas

Aim To examine the association between the crack cocaine cessation and risky sexual behaviors. Design and setting Between June 2002 and March 2005, a sample of African-American residents of Houston, Texas who were using crack at the time of enrollment participated in a cohort study to evaluate per outreach interventions to reduce HIV risk behaviors. The sample for this study consisted of 351 women and men who completed structured surveys at baseline and at six months about socio-demographic characteristics, drug use, and sexual behaviors. Multivariate logistic regression was used to analyze the association between crack cessation and risky sexual behaviors at follow-up, while controlling for confounding characteristics. Measurements Crack cessation was defined as reporting no crack use in the 30 days prior to the follow-up interview. Possible associated factors included unprotected sex, having multiple sex partners, trading sex for money/drugs, crack use, and socio-demographic variables. Findings At the six-month follow-up interview, 21% of participants reported that they had not used crack in the previous 30 days. For women, crack cessation was significantly associated with having only one sex partner at follow-up; for men, crack cessation was significantly associated with being single, separated, or divorced at baseline, having only one sex partner at follow-up, and initiating protected sex by follow-up. Conclusion These findings support previous research indicating that crack use is associated with unprotected sex and multiple sexual partners, as men and women who ceased crack use were less likely to engage in these risky sexual behaviors. Findings demonstrate that treatment for crack use could have a meaningful effect on risky sexual behaviors and HIV/STI prevention.^