共查询到20条相似文献,搜索用时 31 毫秒
1.
Maria Elena Hernandez Abraham Soto-Cid Gonzalo E Aranda-Abreu Rosaura Díaz Fausto Rojas Luis I Garcia Rebeca Toledo Jorge Manzo 《Reproductive biology and endocrinology : RB&E》2007,5(1):11-9
Background
The prostate is a sexual gland that produces important substances for the potency of sperm to fertilize eggs within the female reproductive tract, and is under complex endocrine control. Taking advantage of the peculiar behavioral pattern of copulating male rats, we developed experimental paradigms to determine the influence of sexual behavior on the level of serum testosterone, prostate androgen receptors, and mRNA for androgen receptors in male rats displaying up to four consecutive ejaculations. 相似文献2.
Background
The simultaneously hermaphroditic pond snail, Lymnaea stagnalis, can mate in the male and female role, but within one copulation only one sexual role is performed at a time. Previous work has shown that male motivation is determined by the availability of seminal fluid in the prostate gland, which is detected via a nervous connection by the brain area controlling male behaviour. Based on this knowledge, patterns of sexual role alternations within mating pairs can be explained. 相似文献3.
James K Tsuruta Paul A Dayton Caterina M Gallippi Michael G O’Rand Michael A Streicker Ryan C Gessner Thomas S Gregory Erick JR Silva Katherine G Hamil Glenda J Moser David C Sokal 《Reproductive biology and endocrinology : RB&E》2012,10(1):1-15
Background
Carbamazepine (CBZ) is a first-line antiepileptic drug (AED), although it is also used for the treatments of psychiatric disorders and neuropathic pain. The CBZ utilization has been associated with male reproductive damage, including hormonal alterations, sexual dysfunction and reduction of sperm quality. The wide and long-term use of the CBZ is a common schedule in children and adolescents and alters the testosterone level in adult rats and humans. The objective of this work was to evaluate the CBZ side effects on the ventral prostate of rats from pre-puberty to sexual maturation, since the prostate is an androgen-dependent organ.Methods
Twenty three day-old male albino Wistar rats received CBZ diluted in propylene glycol (20 mg/Kg/i.p via). The treatment lasted 20, 40 and 70 days, according to the different stages of the rat sexual maturation. At the end of each treatment period, ventral prostates were removed and histologically processed. The prostate sections were submitted to the histopathological, morphological and stereological analyses using image analysis system.Results
Reductions of the glandular epithelium, glandular lumen and fibromuscular stroma volume of the ventral prostate were observed in adult rats treated with CBZ since the weaning. Triggering and degranulation of mast cells were observed in the fibromuscular stroma of prepubertal and pubertal CBZ treated rats.Conclusions
The results suggest a direct effect of the CBZ on rat ventral prostate, evidenced by increase of mast cell and macrophage populations during pre-puberty and puberty causing a ventral prostate accentuated damage in the adult phase. 相似文献4.
Background
Arsenic, a major pollutant of water as well as soil, is a known endocrine disruptor, and shows adverse effects on the female reproductive physiology. However, the exact molecular events leading to reproductive dysfunctions as a result of arsenic exposure are yet to be ascertained. This report evaluates the effect and mode of action of chronic oral arsenic exposure on the uterine physiology of mature female albino rats. 相似文献5.
Kuladip Jana Subarna Jana Prabhat Kumar Samanta 《Reproductive biology and endocrinology : RB&E》2006,4(1):9-13
Background
Inorganic arsenic is a major water pollutant and a known human carcinogen that has a suppressive influence on spermatogenesis and androgenesis in male reproductive system. However, the actual molecular events resulting in male reproductive dysfunctions from exposure to arsenic remain unclear. In this context, we evaluated the mode of action of chronic oral exposure of sodium arsenite on hypothalamo-pituitary- testicular activities in mature male albino rats. 相似文献6.
Background
Aquatic plants differ in their development from terrestrial plants in their morphology and physiology, but little is known about the molecular basis of the major phases of their life cycle. Interestingly, in place of seeds of terrestrial plants their dormant phase is represented by turions, which circumvents sexual reproduction. However, like seeds turions provide energy storage for starting the next growing season. 相似文献7.
Background
The daily pattern of nursing of the rabbit pup by the doe is the most important event in the day for the newborn and is neatly anticipated by them. Such anticipation presumably needs a close correlation with changes in hormones that will allow the pups to develop an appropriate behavior. Although a number of circadian functions have been examined in newborn rabbits, there is no information on 24-h pattern of gonadotropin release or on possible sex-related differences in gonadotropin or prolactin (PRL) release of pups. This study examined the 24-h changes of plasma luteinizing hormone (LH), follicle stimulating hormone (FSH) and prolactin (PRL) in 11 days old suckling female and male rabbits left with the mother or after short-term (i.e., 48 h) doe-litter separation. 相似文献8.
Katherine ME Turner Elisabeth J Adams Nigel Gay Azra C Ghani Catherine Mercer W John Edmunds 《Theoretical biology & medical modelling》2006,3(1):3-11
Background
A national chlamydia screening programme is currently being rolled out in the UK and other countries. However, much of the epidemiology remains poorly understood. In this paper we present a stochastic, individual based, dynamic sexual network model of chlamydia transmission and its parameterisation. Mathematical models provide a theoretical framework for understanding the key epidemiological features of chlamydia: sexual behaviour, health care seeking and transmission dynamics. 相似文献9.
Background
It is well known progesterone can have anxiolytic-like effects in animals in a number of different behavioral testing paradigms. Although progesterone is known to influence physiology and behavior by binding to classical intracellular progestin receptors, progesterone''s anxiety reducing effects have solely been attributed to its rapid non-genomic effects at the GABAA receptor. This modulation occurs following the bioconversion of progesterone to allopregnanolone. Seemingly paradoxical results from some studies suggested that the function of progesterone to reduce anxiety-like behavior may not be entirely clear; therefore, we hypothesized that progesterone might also act upon progestin receptors to regulate anxiety.Methodology/Principal Findings
To test this, we examined the anxiolytic-like effects of progesterone in male rats using the elevated plus maze, a validated test of anxiety, and the light/dark chamber in the presence or absence of a progestin receptor antagonist, RU 486. Here we present evidence suggesting that the anxiolytic-like effects of progesterone in male rats can be mediated, in part, by progestin receptors, as these effects are blocked by prior treatment with a progestin receptor antagonist.Conclusion/Significance
This indicates that progesterone can act upon progestin receptors to regulate anxiety-like behavior in the male rat brain. 相似文献10.
Dominique Mazzi Jenni Kes?niemi Anneli Hoikkala Kirsten Klappert 《BMC evolutionary biology》2009,9(1):132
Background
Conflicts of interest between the sexes are increasingly recognized as an engine driving the (co-)evolution of reproductive traits. The reproductive behaviour of Drosophila montana suggests the occurrence of sexual conflict over the duration of copulation. During the last stages of copulation, females vigorously attempt to dislodge the mounting male, while males struggle to maintain genital contact and often successfully extend copulations far beyond the females' preferred duration. 相似文献11.
Background
Many different sexual isolation and sexual selection statistics have been proposed in the past. However, there is no available software that implements all these statistical estimators and their corresponding tests for the study of mating behaviour. 相似文献12.
Rebecca E Oberley Kelli L Goss Amado A Quintar Cristina A Maldonado Jeanne M Snyder 《Reproductive biology and endocrinology : RB&E》2007,5(1):42-9
Background
Surfactant protein D (SP-D) is an innate immune protein that is present in mucosal lined surfaces throughout the human body, including the male reproductive tract. In the present study, we characterized the regulation of SP-D expression in the mouse and rat prostate. 相似文献13.
Louise Winblad von Walter Lena Lidfors Andrzej Madej Kristina Dahlborn Eva Hydbring-Sandberg 《Acta veterinaria Scandinavica》2010,52(1):51
Background
Suckling can be a peaceful or vulnerable event for goats and kids, whereas, separation is suggested as stressful. The aim of this study was to investigate physiology and behaviour in these two different situations in dairy goats. 相似文献14.
Understanding the relationships among variables can be difficult if the variables covary with time. Using a simple, commonly used statistical procedure to control for the passage of time, we demonstrate that some hormonal changes traditionally assumed to be causally related to the transition from sexual to parental behaviour can be explained by seasonal changes in the hormones and the fact that parental behaviour follows sexual behaviour in the course of breeding. We quantified immunoreactive prolactin (ir-prolactin) and testosterone concentrations in laboratory-housed and free-living male American kestrels, Falco sparverius, over the course of the breeding season and during sexual and parental phases of reproduction. We found that ir-prolactin increased while testosterone decreased with the transition from sexual to parental behaviour. ir-Prolactin increased with date (i.e. seasonally), whereas testosterone peaked when the frequency of clutch initiation was greatest and then decreased with date thereafter. Controlling for the effects of date eliminated the change in ir-prolactin associated with the transition from sexual to parental behaviour, revealing that prolactin variation associated with this behavioural transition in male kestrels is due, in large part, to seasonal changes in hormone concentrations and the serial nature of these behavioural states. Controlling for the effects of date further revealed that the testosterone difference between sexual and parental males decreases seasonally. It is possible that other phenomena traditionally attributed to environmental, behavioural, social, or other variables also may be explained by the association between such variables and the passage of time. 相似文献
15.
Ongoing development of brain systems for social behaviour renders these systems susceptible to the influence of stressors in adolescence. We previously found that adult male rats that underwent social instability stress (SS) in mid-adolescence had decreased sexual performance compared with control males (CTL). Here, we test the hypotheses that SS in adolescence decreases the “attractiveness” of male rats as sexual partners compared with CTL rats and that dominance status is a protective factor against the effects of SS. The main prediction was that females would spend more time with CTL males than SS males, and that this bias would be greater for submissive than for dominant rats. Among dominant pairs (n = 16), females preferred SS males, spending more time with and visiting more often SS than CTL males (each pair tested 5 ×), and SS males had shorter latencies to ejaculation, shorter inter-ejaculation intervals, and made more ejaculations compared with CTL males. Among submissive pairs (n = 16), females spent more time with, visited more often, and displayed more paracopulatory behaviour with CTL than with SS males, and differences in sexual performance between SS and CTL males were modest and in the opposite direction from that in dominant pairs. The heightened motivation of SS males relative to CTL males for natural rewards may have attenuated differences in sexual performance in a paced mating context. In sum, the experience of stress in adolescence leads to long-lasting changes in males that are perceptible to females, are moderated by social status, and influence sexual behaviour. 相似文献
16.
Background
Despite growing evidence that population dynamic processes can have substantial effects on mating system evolution, little is known about their effect on mating rates in simultaneous hermaphrodites. According to theory, mating rate is expected to increase with mate availability because mating activity is primarily controlled by the male sexual function. A different scenario appears plausible in the hermaphroditic opisthobranch Chelidonura sandrana. Here, field mating rates are close to the female fitness optimum, suggesting that mating activity remains unresponsive to variation in mate availability. 相似文献17.
We investigated male sexual behaviour and the cost of sexual harassment, as measured by the reduction of female feeding time in the presence of a male, in a cave-dwelling population of Poecilia mexicana, in which sexual harassment does not occur naturally. We asked whether the lack of sexual harassment in this population is due to low sexual activity of the males, or low feeding motivation of the females. We experimentally increased the sexual activity of males or the females feeding motivation, or we used a combination of both treatments. Female feeding time was not lower in the presence of a male than in the presence of a female after sexual deprivation of the males or food deprivation of the females. Only in the combined experiment was female feeding time lower in the presence of a large male than in the presence of a small male, indicating a weak effect of sexual harassment by large males. Virgin females did not suffer a cost of sexual harassment, indicating that sexual experience does not cause the lack of sexual harassment in cave mollies. Males from a surface population, where sexual harassment occurs, significantly reduced the feeding time of cave-dwelling females even though these males exhibited surprisingly little sexual behaviour. The sexual activity of cave mollies did not correlate with male body size in any experiment, indicating that even after sexual deprivation, small cave molly males do not switch to the alternative mating behaviour known in surface-dwelling P. mexicana, where sexual activity is correlated negatively with male body size. 相似文献
18.
Stephanie Filleur Jennifer Hirsch Aline Wille Margarete Schön Christian Sell Michael H Shearer Thomas Nelius Ilse Wieland 《Cancer cell international》2009,9(1):28-9
Background
The gene encoding integrator complex subunit 6 (INTS6), previously known as deleted in cancer cells 1 (DICE1, OMIM 604331) was found to be frequently affected by allelic deletion and promoter hypermethylation in prostate cancer specimens and cell lines. A missense mutation has been detected in prostate cancer cell line LNCaP. Together, these results suggest INTS6/DICE1 as a putative tumor suppressor gene in prostate cancer. In this study, we examined the growth inhibitory effects of INTS6/DICE1 on prostate cancer cells. 相似文献19.
Phelipe O Favaron Anthony M Carter Carlos E Ambrósio Adriana C Morini Andrea M Mess Moacir F de Oliveira Maria A Miglino 《Reproductive biology and endocrinology : RB&E》2011,9(1):55
Background
Sigmodontinae, known as "New World rats and mice," is a large subfamily of Cricetidae for which we herein provide the first comprehensive investigation of the placenta. 相似文献20.