Viagra Increases Release Of Key Reproductive Hormone, Study Finds
研究发现伟哥增加了关键发育激素的释放
Science Daily — Researchers at the University of Wisconsin-Madison report this month that sildenafil increases the amount of oxytocin released by stimulation of the posterior pituitary gland, a small structure directly underneath the brain that regulates hormone levels in response to neural signals.
每日科学——威斯康星-麦迪逊大学的研究者本月报道，西地那非可以通过刺激正好位于大脑下的一个结构——垂体后叶——该结构通过对神经信号的反映调节激素水平，增加缩宫素的释放。
The finding is the first indication of a chemical mechanism through which erectile dysfunction drugs like Viagra may have physical effects besides increasing blood flow to sexual organs, says study author Meyer Jackson, a physiology professor at the UW-Madison School of Medicine and Public Health.
这个发现第一次显示了为什么像伟哥这一类勃起功能障碍药物在增加性器官血流时还对生理有一定影响，署名研究者Meyer Jackson说，他是威斯康星-麦迪逊大学药物及公共健康学院的生理学教授。
Sometimes called the \"love hormone\" or \"cuddle chemical,\" oxytocin plays several important roles in social interactions and reproduction, including triggering uterine contractions and lactation. It is also released during orgasm and has been linked to sexual arousal.
有时被称为“爱情激素”或“拥抱反应物”的缩宫素在社交以及生育包括促进子宫收缩以及分娩方面有着数个重要作用。它在高潮时也被释放并且同性觉醒相关。
Oxytocin release is regulated by an enzyme that acts like a braking system, limiting hormone release by dampening neural excitation of the cells. This same enzyme, phosphodiesterase type 5, also limits blood flow by contracting the muscles around blood vessels.
缩宫素的释放被一种作用类似刹车的酶所控制，抑制神经细胞的兴奋就可以减少激素释放。同一种酶，5型磷酸二酯酶也通过收缩血管壁平滑肌减少血流。
In both places, sildenafil works by blocking this enzyme, essentially releasing the brakes, explains Jackson. In blood vessels, relaxing smooth muscle increases blood flow, which corrects erectile dysfunction, and in the posterior pituitary, the cells become more responsive. \"The same stimulation will produce more [oxytocin] release.\" He says, \"I think this is a missing link in terms of trying to sort out the issues around whether there are additional effects of phosphodiesterase type 5 inhibitors,\" which include Viagra, Levitra and Cialis.
Jackson解释说，在两种情况下，西地那非均可抑制这种酶发挥其“刹车”作用。在血管中，松弛平滑肌细胞可以增加血流量，这种作用可以纠正勃起功能障碍，在垂体中细胞的反应性被加强。“同样的刺激将导致更多的（缩宫素）释放。”他说，“我想这是个在挑选5型磷酸二酯酶抑制剂是否有其他作用时被遗漏的角落，”这些药物包括伟哥、爱立达和希爱力。
The new report was published online Aug. 9 and appears in an upcoming issue of the Journal of Physiology. In the study, the scientists measured oxytocin released from rat pituitaries in response to neural stimulation. When the pituitaries were treated with sildenafil, they responded to the stimulation by releasing three times as much oxytocin as they did without the drug. Importantly, the drug had little if any effect on hormone release in the absence of stimulation, Jackson says. \"Erectile dysfunction drugs do not induce erections spontaneously, they enhance the response to sexual stimulation,\" he says. \"The same thing is happening in the posterior pituitary - Viagra will not induce the release of oxytocin on its own, but it will enhance the amount of release you get in response to electrical stimulation.\"
这个新报告于8月9日在网上更新并且成为了《生理学》杂志的下一个话题。在这个试验中，科学家们测量了鼠垂体接受神经冲动后缩宫素的释放量。当对垂体使用西地那非时，释放的缩宫素的量是不使用时的3倍。
Though he doesn't think his findings raise any significant safety issues related to Viagra use, he does think it provides strong rationale for studies of additional effects and new potential uses. \"A big question raised by our study is, will sildenafil do the same thing to the nerve terminals that release oxytocin [in the brain]\"\" he says. The cells that supply oxytocin to the pituitary come from a brain structure called the hypothalamus, which also sends hormones throughout the brain.
虽然他认为他的发现中没有任何同伟哥使用相关的安全性问题，他也不认为他的发现给其他的作用以及新的潜在治疗方向提供了支持。“我们的研究提出的一大问题是，是否西地那非可以（像对大脑那样）促进神经末梢缩宫素的释放。”他说。在脑中向下丘脑提供缩宫素的细胞被称作视丘下部，这一部分也向大脑提供激素。
Though sildenafil's effects on these pathways are still unknown, work by other researchers has shown that oxytocin-sensitive cells in the brain play a role in the neural control of erectile responses, suggesting that Viagra and its kin may work through multiple channels.
虽然西地那非对这些通道的作用仍不为人知，其他研究者的工作已经显示脑中的缩宫素敏感细胞同控制勃起反应的神经元相关，指出了伟哥及其同类产品可能通过多种通道起作用。
The famous blue pills could have other uses as well. Oxytocin has been linked to the ability to make strong social bonds, while sildenafil was recently shown to improve hamsters' abilities to adjust the timing of their internal clocks to overcome simulated jet lag. \"This is one piece in a puzzle in which many pieces are still not available,\" Jackson says. \"But it raises the possibility that erectile dysfunction drugs could be doing more than just affecting erectile dysfunction.\"
这个著名的蓝色小药片还有着其他的作用。缩宫素同强大的社交能力是有关的，并且最近西地那非被证实可以增强仓鼠调整其生物钟以适应人造时差的能力。“这是很多没有办法解释的问题中的一个，” Jackson说，“但是它增加了治疗勃起障碍药物除治疗勃起障碍之外其他问题的可能性。”
The study was co-authored by Zhenjie Zhang and Vitaly Klyachko. Funding for the research came from the National Institutes of Health.
Zhenjie Zhang和Vitaly Klyachko也为该研究的署名作者。该研究由国立卫生研究院资助进行。
研究发现伟哥增加了关键发育激素的释放
每日科学——威斯康星-麦迪逊大学的研究者本月报道，西地那非可以通过刺激正好位于大脑下的一个结构——垂体后叶——该结构通过对神经信号的反映调节激素水平，增加缩宫素的释放。
这个发现第一次显示了为什么像伟哥这一类勃起功能障碍药物在增加性器官血流时还对生理有一定影响，署名研究者Meyer Jackson说，他是威斯康星-麦迪逊大学药物及公共健康学院的生理学教授。
有时被称为“爱情激素”或“拥抱反应物”的缩宫素在社交以及生育包括促进子宫收缩以及分娩方面有着数个重要作用。它在高潮时也被释放并且同性觉醒相关。
缩宫素的释放被一种作用类似刹车的酶所控制，抑制神经细胞的兴奋就可以减少激素释放。同一种酶，5型磷酸二酯酶也通过收缩血管壁平滑肌减少血流。
Jackson解释说，在两种情况下，西地那非均可抑制这种酶发挥其“刹车”作用。在血管中，松弛平滑肌细胞可以增加血流量，这种作用可以纠正勃起功能障碍，在垂体中细胞的反应性被加强。“同样的刺激将导致更多的（缩宫素）释放。”他说，“我想这是个在挑选5型磷酸二酯酶抑制剂是否有其他作用时被遗漏的角落，”这些药物包括伟哥、爱立达和希爱力。
这个新报告于8月9日在网上更新并且成为了《生理学》杂志的下一个话题。在这个试验中，科学家们测量了鼠垂体接受神经冲动后缩宫素的释放量。当对垂体使用西地那非时，释放的缩宫素的量是不使用时的3倍。
虽然他认为他的发现中没有任何同伟哥使用相关的安全性问题，他也不认为他的发现给其他的作用以及新的潜在治疗方向提供了支持。“我们的研究提出的一大问题是，是否西地那非可以（像对大脑那样）促进神经末梢缩宫素的释放。”他说。在脑中向下丘脑提供缩宫素的细胞被称作视丘下部，这一部分也向大脑提供激素。
虽然西地那非对这些通道的作用仍不为人知，其他研究者的工作已经显示脑中的缩宫素敏感细胞同控制勃起反应的神经元相关，指出了伟哥及其同类产品可能通过多种通道起作用。
这个著名的蓝色小药片还有着其他的作用。缩宫素同强大的社交能力是有关的，并且最近西地那非被证实可以增强仓鼠调整其生物钟以适应人造时差的能力。“这是很多没有办法解释的问题中的一个，” Jackson说，“但是它增加了治疗勃起障碍药物除治疗勃起障碍之外其他问题的可能性。”
Zhenjie Zhang和Vitaly Klyachko也为该研究的署名作者。该研究由国立卫生研究院资助进行。 |
发表于 2007-9-4 11:27:45
