- UID
- 60707
- 热情
- 4261
- 人气
- 1954
- 主题
- 2
- 帖子
- 19329
- 精华
- 49
- 积分
- 12903
- 分享
- 0
- 记录
- 0
- 相册
- 0
- 好友
- 0
- 日志
- 1
- 在线时间
- 3161 小时
- 注册时间
- 2006-1-13
- 阅读权限
- 30
- 最后登录
- 2022-3-6
升级 58.06% - UID
- 60707
- 热情
- 4261
- 人气
- 1954
- 主题
- 2
- 帖子
- 19329
- 精华
- 49
- 积分
- 12903
- 阅读权限
- 30
- 注册时间
- 2006-1-13
|
先说一下女性能够产生乳汁(lactate)需要两种激素(hormone,也叫荷尔蒙): 催乳激素(prolactin)+催产素(oxytocin).
催乳激素(prolactin)是产生乳汁(lactate)的主要激素(hormones),它能让lactiferous sinus(乳腺窦)分泌乳汁,通过holocrine(全泌:一种分泌方式,主要是细胞在分泌的同时失去一些细胞本身的物质的方式--编者)的方式。。。而催产素(oxytocin)则主要让smooth muscle contracts(平滑肌的收缩)然后把乳汁挤出来,以及在labour(分娩)的过程中让uterine wall contracts(子宫壁收缩)好让婴儿从vagina(阴道)出来......
我有一个疑问,因为曾在National Hospital工作过的奥大妇科专家Dr. Larry Chamely给我上课的时候说他不知道为什么男人会develop breasts(进化出乳房)....我觉得一个原因是用来展示的,当男性过度使用Pectoralis Major(胸大肌--在乳房正下放的那块肌肉,俗称胸肌--编者)的时候,便能让breasts(如芳)一起跳动,俗称跳奶。。。。。
我的疑问是:如果给一个男性同时两种激素(hormone), 即催乳激素(prolactin)+催产素(oxytocin). can he lactate???????因为理论上男女的乳房的结构都相似的,都是homologus(同源器官)。。。
我拿这个问题去问Larry,他的回答是No.
他说女性和男性另一点不同的是女性在puberty(青春期)之后breasts受另外两种女性hormones的刺激:oestrogen(雌性激素) and progesterone(孕激素),这两种hormones也是女性menstral cycle(月经)的hormones...当然还有lutenising hormone(黄体酮)导致排卵。。。。
而这两种hormones是男人不具有的,所以他说男性breasts的ductile system(乳汁管)没有女性那么完备,所以他的原话结论是“I am not sure if a male given Prolactin and oxytocin would lactate because the ductile/secretory system is not as well developed as in an adult female ”即“我不确定如果给一个男性催乳激素(prolactin)+催产素(oxytocin)他是否会产奶因为男性乳房里头的ductile system(乳汁管)没有进化的和女性一样。
最后还表扬了我,说我这个是“good thought!!!”
看来reproduction还是挺有意思的,如果让一个男性在puberty的时候植入oestrogen and progesterone,那么他是否能够lactate呢???如果我有幸读到p.H.D的话,这将会成为我的论文的课题吧。。。。。。
下面是网友提供的有关这个课题的原文:
Male lactation
From Wikipedia, the free encyclopedia
The phenomenon of male lactation in humans has become more common in recent years due to the use of medications that stimulate a human male's mammary glands. Though human males have nipples, it is not so often understood that they also have mammary glands. Ordinarily the mammary tissue is low in volume and cannot be noticed. Under the appropriate hormonal stimulus—the hormonal stimulus that nature provides to human females when they become pregnant and give birth—the mammary glands of human males can also produce milk. The volume of milk produced is low relative to that of a lactating female.
Male lactation is most commonly caused by hormonal treatments given to men suffering from prostate cancer. Female hormones are used to retard the production of cancerous prostate tissue, but the same hormones also stimulate the mammary glands. Male-to-female transsexuals may also produce milk due to the hormones they take to reshape their bodies. Extreme stress combined with demanding physical activity and a shortage of food has also been known to cause male lactation. The phenomenon was first studied in survivors of the liberated Nazi concentration camps after World War II. Some American POWs returning from the Korean and Vietnam Wars also experienced male lactation.
The phenomenon of male lactation occurs in some non-human species, and the lactating males may assist in the nursing of their infants. One species of fruit bat, the Dayak fruit bat (Dyacopterus spadiceus), is notable for this reason. According to several sources, male lactation and even nursing have occasionally been observed in humans.
[edit]
References
Angier, Natalie; New York Times, February 24, 1994. Cr. J. Covey.
Francis, Charles M., et al; "Lactation in Male Fruit Bats," Nature, 367:691, 1994.
Fackelmann, K.A.; Science News, 145:148, 1994.
Anomalies and Curiosities of Medicine G.M. Gould and W.L. Pyle
然后是我的翻译,这是我第一次搞翻译啊,虽然都看得明白,但是怎么翻译成中文的书面体有些句子看起来别扭,希望各位大侠们不要见笑,我只是一个stage II student而已!!!
男性的乳汁分泌
在人类中男性产奶的现象在近几年已经越来越趋向于平常,原因在于可以用医学的刺激男性乳房中的乳腺,尽管男性有进化了自己的乳房,但是一般研究表明,男性一般不会进化出自己的乳腺(乳汁分泌的必要腺体)。一般情况下乳腺作为一个非常小的腺体是不容易被察觉的,但是在孕妇们一些激素的刺激下它们可以导致分娩—同时的乳腺可以让女性产奶(在分娩之后)
男性产奶大部分情况下是由于激素的前列腺癌症的治疗过程中产生的。此方法采用的是女性的激素(黄体酮和孕激素)来延迟癌细胞在前列腺组织中的分裂,但与此同时这些激素也刺激了乳腺,导致(一些)男性产生了乳汁。变性手术也可以导致[男性产生乳汁,原因是大量的女性激素在改变第二性征,包括喉结,体形身材的同时也改变了原本男性中乳房的结构。。。暴露于严重的压力和外界物理性的活动行为以及食物的短缺也可以使男性分泌乳汁。这种现象最先是在第二次世界大战后从越南,朝鲜返回美国的士兵当中出现而被发现从而进行研究的。
男性的动物也有产奶的现象,但一般情况下这些男性都承担了一定程度的抚育幼体的过程。举例说明,果蝙蝠(Dyacopterus spadices)就是一个很显著的例子。在一些其他的情况下,人类中有时候也会出现和蝙蝠一样的情况,即男性产奶和照顾婴儿。
参考文献:
Angier, Natalie; New York Times, February 24, 1994. Cr. J. Covey.
Francis, Charles M., et al; "Lactation in Male Fruit Bats," Nature, 367:691, 1994.
Fackelmann, K.A.; Science News, 145:148, 1994.
Anomalies and Curiosities of Medicine G.M. Gould and W.L. Pyle
[ 本帖最后由 Anatomy 于 2006-6-22 09:42 编辑 ] |
|