Fertility diminution in female rats with experimental chronic nephrosis

Recovery home networks as social capital

Ensuring recovery home residents' social integration into a home environment is important for preventing early dropout and facilitating sustained recovery. Social capital theory may provide an explanation for how recovery homes may protect residents and improve recovery rates. However, little is known about how social capital in recovery home environments is structured and accessed. Recovery homes may increase social capital by sharing bonds through friendships, lending money, and advice-seeking. The current study describes social network cross sectional data obtained from a study of 42 Oxford House recovery homes, in three locations in the US (North Carolina, Texas, and Oregon). The residents rated each member of their house on the dimensions of friendship, money loaning, and advice seeking to assess how each resident views one another on these dimensions. The research used baseline data from a larger longitudinal study, and although some data were presented for the full sample (APL, isolates, mean reciprocity and density), the results primarily focused on case studies for three of the participating Oxford Houses-with examples of low, median, and high "connected" houses respectively. Standard measures of network structures were calculated for each home. Although all Oxford Houses follow the same house rules, they were found to vary in network structure. Findings indicated a considerable range of interconnectedness among residents in these houses, with friendship being the most common relationship, willingness to lend money less common, and advice-seeking the least common. The findings on friendship, willingness to lend, and advice-seeking provide promising leads about what occurs among the social networks within these complex eco-systems, and may provide ways to better understand and facilitate resident social integration into these settings.

Chronic 17β-estradiol pretreatment has pronociceptive effect on behavioral and morphological changes induced by orofacial formalin in ovariectomized rats

Background

The prevalence of craniofacial pain disorders show sexual dimorphism with generally more common appearance in women suggesting the influence of estradiol, but the exact cause remains unknown. The common point in the pathogenesis of these disorders is the activation of trigeminal system. One of the animal experimental models of trigeminal activation is the orofacial formalin test, in which we investigated the effect of chronic 17β-estradiol pretreatment on the trigeminal pain-related behavior and activation of trigeminal second-order neurons at the level of spinal trigeminal nucleus pars caudalis (TNC).

Methods

Female Sprague Dawley rats were ovariectomized and silicone capsules were implanted subcutaneously containing cholesterol in the OVX group and 17β-estradiol and cholesterol in 1:1 ratio in the OVX+E₂ group. We determined 17β-estradiol levels in serum after the implantation of capsules. Three weeks after operation, 50 µL of physiological saline or 1.5% of formalin solution was injected subcutaneously into the right whisker pad of rats. The time spent on rubbing directed to the injected area and c-Fos immunoreactivity in TNC was measured as the formalin-induced pain-related behavior, and as the marker of pain-related neuronal activation, respectively.

Results

The chronic 17β-estradiol pretreatment mimics the plasma levels of estrogen occurring in the proestrus phase and significantly increased the formalin-induced pain-related behavior and neuronal activation in TNC.

Conclusion

Our results demonstrate that the chronic 17β-estradiol treatment has strong pronociceptive effect on orofacial formalin-induced inflammatory pain suggesting modulatory action of estradiol on head pain through estrogen receptors, which are present in the trigeminal system.

Parenting Strain among Mexican-origin Mothers: Differences by Parental Legal Status and Neighborhood

Despite increasing recognition of the critical importance of legal status for understanding the well-being of immigrants and their families, there has been scant research on this topic due to data limitations. Using Wave 1 of the Los Angles Family and Neighborhood Survey (2000-2002) and the 2000 decennial census, we investigate how parenting strain among Mexican-origin mothers varies by legal status and neighborhood context. We find significant differences in parenting strain by nativity and legal status, with undocumented mothers reporting the lowest level. Results from multilevel models with cross-level interactions reveal that the influence of neighborhood immigrant concentration differs by legal status. Percent foreign born in the neighborhood is associated with reduced parenting strain for documented Mexican-origin mothers while it is associated with heightened parenting strain for undocumented Mexican-origin mothers. Findings provide empirical support for the need to recognize legal status distinctions in studies of the well-being of immigrants and their families.

Adaptors, Junction Dynamics, and Spermatogenesis1

Adaptors are component proteins of junctional complexes in all epithelia, including the seminiferous epithelium of the mammalian testis. They recruit other regulatory and structural proteins to the site of both anchoring junctions (such as cell-cell actin-based adherens junctions [AJs], e.g., ectoplasmic specialization [ES] and tubulobulbar complex, which are both testis-specific cell-cell actin-based AJ types, and cell-cell intermediate filament-based desmosome-like junctions) and tight junctions (TJ). Furthermore, adaptors per se can be substrates and/or activators of kinases or phosphatases. As such, the integrity of cell junctions and the regulation of junction dynamics during spermatogenesis rely on adaptors for their ability to recruit and link different junctional components to the same site and to tether transmembrane proteins at both anchoring and TJ sites to the underlying cytoskeletons, such as the actin filaments, intermediate filaments, and microtubules. These protein-protein interactions are possible because adaptors are composed of conserved protein binding domains, which allow them to link to more than one structural or signaling protein, recruiting multi-protein complexes to the same site. Herein, we provide a timely review of adaptors recently found at the sites of AJ (e.g., ES) and TJ. In addition, several in vivo models that can be used to delineate the function of adaptors in the testis are described, and the role of adaptors in regulating junction dynamics pertinent to spermatogenesis is discussed.

Epitope-dependent localization of estrogen receptor-alpha, but not -beta, in en face arterial endothelium

Rapid, nongenomic effects of 17 beta-estradiol (E(2)) in endothelial cells are postulated to arise from membrane-associated estrogen receptors (ERs), which have not been visualized in vascular tissue. To identify membrane ERs, we used multiple site-directed ER alpha or ER beta antibodies to label en face rat cerebral and coronary arterial endothelia. Western blots revealed a novel 55-kDa ER alpha isoform. Three-dimensional images of cells labeled with these antibodies and markers for the nucleus and caveolin-1 were acquired with a wide-field microscope, deconvolved, and numerically analyzed. We found ER alpha in the nucleus and cell periphery, where one-third colocalized with caveolin-1. The receptor location was dependent on the epitope of the antibody. Human ovarian surface epithelium produced similar results; but in rat myometrium, the distribution was epitope independent and nuclear. ER beta distribution was predominantly intranuclear and epitope independent. A small amount of ER alpha colocalized with ER beta within the nucleus. The results were identical in both arterial preparations and insensitive to E(2). We postulate that the different ER alpha conformations at the membrane, in the nucleus, and between different cell types allow E(2) to trigger cell- and location-specific signaling cascades.

Dynamic tests and FSH biological activity in female rats with acute nephrotic syndrome

To investigate the pituitary-ovarian status during the acute state of the nephrotic syndrome, a sequence of experiments were undertaken in adult female rats after a single dose of the puromycin aminonucleoside (PAN). The functional condition of the hypophyseal-ovarian unit was determined in control and nephrotic rats by two dynamic tests. In the first one, 10 days after PAN or placebo administration female rats were stimulated with LHRH (300 ng/100 g body wt) and samples were collected at 0, 20, 40, 60 and 80 min after releasing factor administration. The second dynamic test, which was performed in control and nephrotic rats, consists of one (day 10 after PAN) or four (between days 7-10 after PAN) doses of hCG (8 UI), respectively. In all cases, serum samples were collected on day 10. In addition, the relative in vitro biological activity of FSH from control and nephrotic rats before and after LHRH stimulus was determined. The results reveal that after a stimulatory dose of LHRH the secretion of LH was significantly diminished in nephrotic rats at all registered times. By contrast, normal response was observed in terms of FSH secretion in nephrotic females. On the other hand, no ovarian response, in terms of progesterone or estradiol synthesis, was observed in nephrotic rats after either one or four stimuli with hCG Interestingly, in spite of the normal or high concentrations of FSH, the biological activity of FSH was totally abolished in nephrotic rats. On the whole, the results from this study indicate that the nephrotic syndrome had a harmful effect on the pituitary-ovarian unit, and strongly suggest that the endocrine dysfunction could be initiated at the hypophysial level; even though a specific ovarian damage is also predictable.

Evaluation of the pituitary-testicular function during experimental nephrosis

To investigate the pituitary-testicular function in nephrotic rats, a sequence of experiments was undertaken in adult male rats after a single dose of puromycin aminonucleoside (PAN). Endocrine modifications were evaluated chronologically throughout the experimental disease in order to determine the appearance of hormone alterations which lead to the axis dysfunction. Serum concentration of LH, FSH, androstenedione, total and free testosterone, estradiol as well as urine testosterone were measured by specific RIAs on days 3, 7 and 10 after treatment on nephrotic and control groups. Prolactin was also evaluated on day 10. Likewise, total weight of various androgen responsive tissues from both groups was recorded, and the number of androgen receptor (AR) binding sites were determined. To know the functional status of the hipophyseal-testicular unit, groups of nephrotic and control rats were stimulated with LHRH (300 ng/100 g b.w.) or with one or four doses of hCG (8 UI), respectively. Additionally, the relative in vitro biological activity of FSH from nephrotic and control rats before and after LHRH stimulus was determined. The results from the hormonal profile revealed clear endocrine disorders characterized by a progressive diminution of all serum hormones except prolactin and urine testosterone, which remained unmodified. The weight of the main androgen responsive tissues, the ventral prostate and the seminal vesicle, decreased parallelly to androgen diminution. The binding analysis of AR shows a significant elevation of the available androgen sites in all analyzed tissues except kidney and hypothalamus. The secretion of LH and FSH from nephrotic animals after LHRH administration was lower than that from intact animals at the registered times. Interestingly, the biological activity of FSH from nephrotic rats was not detectable at both, before and after LHRH administration. Testicular response to hCG stimuli, in terms of testosterone synthesis was not significantly different in the two groups analyzed with respect to the intact animals. By contrast, no response was observed in terms of estradiol production at either one or four doses of hCG. On the whole, the results presented herein allow us to conclude that experimental nephrosis has a harmful effect on the pituitary-testicular axis, and strongly suggests that the endocrine dysfunction is initiated at the hypophyseal level; even though a specific testicular damage is also present.