章节大纲

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    Milk on Demand
    ::供需牛奶

    This adorable nursing infant is part of a positive feedback loop. When he suckles on the nipple, it sends to his mother’s hypothalamus . Those nerve impulses “tell” her pituitary gland to release the prolactin into her bloodstream. Prolactin travels to the mammary glands in the breasts and stimulates milk production, which motivates the infant to keep suckling.
    ::这个可爱的哺乳婴儿是一个积极的反馈循环的一部分。 当他舔乳头时,它会将乳头送到他母亲的下脑膜。 这些神经冲动“把”她的脑下腺释放到她的血液中去。 蛋白质会到乳房的哺乳腺,刺激牛奶生产,这促使婴儿继续吸奶。

    What Is the Pituitary Gland?
    ::什么是光纤甘蓝?

    The pituitary gland is the master gland of the , which is the system of glands that secrete hormones into the bloodstream. Endocrine hormones control virtually all physiological processes. They control growth, sexual maturation, , body temperature, , and metabolism . The pituitary gland is considered the master gland of the endocrine system, because it controls the rest of the endocrine system. Many pituitary hormones either promote or inhibit hormone secretion by other .
    ::脑垂状腺是内分泌系统的主腺,它是一种将荷尔蒙分泌到血液中的腺系统。内分泌激素控制着几乎所有生理过程。它们控制着生长、性成熟、体温、体温和新陈代谢。脑垂状腺被认为是内分泌系统的主腺,因为它控制着内分泌系统的其他部分。许多脑膜荷尔蒙要么会促进,要么会抑制他人对荷尔蒙的分泌。

    Structure and Function of the Pituitary Gland
    ::管道盖兰的结构和功能

    The pituitary gland is about the size of a pea. It protrudes from the bottom of the hypothalamus at the base of the inner brain (see the figure ). The pituitary is connected to the hypothalamus by a thin stalk (called the infundibulum). and nerves in the stalk allow direct connections between the hypothalamus and pituitary gland.
    ::垂体腺与豆子大小差不多。 它从内脑底部的低丘脑底部(见图 ) 。 垂体腺与低丘脑相连, 由一条细小的尾巴( 称为直原) 。 尾部的神经可以让低丘脑与直栖腺直接相连 。

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    The pituitary gland in the endocrine system is closely connected to the hypothalamus in the brain.
    ::内分泌系统中的脑垂体腺与大脑的脑下脑瘤紧密相连。

    The pituitary gland consists of two bulb-like lobes: an anterior lobe and a posterior lobe. The two lobes are shown in the diagram .
    ::脑垂状腺由两种类似灯泡的叶叶组成:前额叶和后额叶。图中显示了这两个叶叶。

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    Both anterior and posterior lobes of the pituitary gland are directly connected to the hypothalamus by capillaries (anterior lobe) and nerve axons (posterior lobe).
    ::脊下腺的前部和后部叶子都直接与下脑骨直接相连,由刺膜(前额叶)和神经斧子(前额叶)直接相连。

    Anterior Lobe
    ::离家居室居室居室

    The anterior pituitary is the lobe is at the front of the pituitary gland. It synthesizes and releases hormones into the . The table shows some of the endocrine hormones released by the anterior pituitary, including their targets and effects.
    ::前脑垂体是垂体在垂体腺前部,它合成并释放荷尔蒙进入。表格显示了内分泌内分泌内分泌内分泌内分泌释放的一些荷尔蒙,包括它们的目标和效果。

    Anterior Pituitary Hormones
    Hormone Target Effect(s)
    Adrenocorticotropic hormone (ACTH) Adrenal glands Stimulates the cortex of each adrenal gland to secrete its hormones
    Thyroid-stimulating hormone (TSH) Thyroid gland Stimulates the thyroid gland to secrete thyroid hormone
    Growth hormone (GH) Body Stimulates body cells to synthesize and grow
    Follicle-stimulating hormone (FSH) Ovaries , testes Stimulates the ovaries to develop mature eggs ; stimulates the testes to produce
    Luteinizing hormone (LH) Ovaries, testes Stimulates the ovaries and testes to secrete sex hormones ; stimulates the ovaries to release eggs
    Prolactin (PRL) Mammary glands Stimulates the mammary glands to produce milk

    The anterior pituitary gland is regulated mainly by hormones from the hypothalamus. The hypothalamus secretes hormones (called releasing hormones and inhibiting hormones) that travel through capillaries directly to the anterior lobe of the pituitary gland. You can see the capillary connection in the diagram . The hormones stimulate the anterior pituitary to either release or stop releasing particular pituitary hormones. Several of these hypothalamic hormones and their effects on the anterior pituitary are shown in the table .
    ::皮下垂状腺主要由下脑膜的荷尔蒙调节。下脑膜分泌激素(称为释放激素和抑制激素)直接穿刺到垂下腺前部。您可以看到图表中的毛细线连接。激素刺激前脑部分泌物释放或停止释放特定垂下荷尔蒙。表格中显示了这些低脑荷尔蒙及其对前脑垂体的影响。

    Hypothalamic Hormones and Their Effects on the Anterior Pituitary

    Hypothalamic Hormone
    ::假冒致幻觉激素

    Effect on Anterior Pituitary
    ::对内下管道的影响

    Thyrotropin releasing hormone (TRH)
    ::甲状腺释放激素(TRH)

    Release of thyroid stimulating hormone (TSH)
    ::甲状腺刺激激素(TH)释放

    Corticotropin releasing hormone (CRH)
    ::Corticotropin 释放激素(CRH)

    Release of adrenocorticotropic hormone (ACTH)
    ::释放亚丁皮质激素(ACTH)

    Gonadotropin releasing hormone (GnRH)
    ::Gonadotropin 释放激素(GNRH)

    Release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH)
    ::释放泡泡刺激激素(FSH)和润滑荷尔蒙(LH)

    Growth hormone releasing hormone (GHRH)
    ::增长激素释放激素激素(GHRH)

    Release of growth hormone (GH)
    ::生长激素释放(GH)

    Growth hormone inhibiting hormone (GHIH) (Somatostatin)
    ::抑制荷尔蒙的增长激素(GHIH)(Somatostatatain)

    Stopping of growth hormone release
    ::停止释放生长激素

    Prolactin releasing hormone (PRH)
    ::蛋白素释放激素(PRH)

    Release of prolactin
    ::蛋白素释放

    Prolactin inhibiting hormone (PIH) (Dopamine)
    ::抑制激素(多氯胺酮)

    Stopping of prolactin release
    ::停止 plaactin 释放

    Posterior Lobe
    ::下水道

    The posterior pituitary is the lobe is at the back of the pituitary gland. This lobe does not synthesize any hormones. Instead, the posterior lobe stores hormones that come from the hypothalamus along the axons of nerves connecting the two structures (also shown in the diagram above). The posterior pituitary then secretes the hormones into the bloodstream as needed. Hypothalamic hormones secreted by the posterior pituitary include vasopressin and oxytocin .
    ::脑后垂体是垂体腺的后部。 脑后部没有合成任何荷尔蒙。 相反, 脑后垂体在连接两个结构的神经轴轴上储存了来自下丘脑的荷尔蒙( 也见上图 ) 。 脑后垂体随后将荷尔蒙分解到血液流中。 脑后垂体不包含任何荷尔蒙, 包括血管压抑剂和催产素。

    • Vasopressin (also called antidiuretic hormone , or ADH) helps maintain in body . It stimulates the to conserve water by producing more concentrated urine . Specifically, vasopressin targets ducts in the kidneys and makes them more permeable to water. This allows more water to be resorbed by the body, rather than excreted in urine.
      ::Vassopressin (亦称抗二尿素激素(ADH)) 有助于身体保持。 它通过产生更集中的尿液来刺激节水。 具体地说,血管压抑剂的目标是肾脏中的输气管,使其更容易渗透到水中。 这使得更多的水可以由身体转接,而不是排泄在尿中。
    • Oxytocin (OXY) targets cells in the uterus to stimulate uterine contractions, as in childbirth. It also targets cells in the breasts of a nursing mother to stimulate the letdown of milk.
      ::Oxytocin(OXY)针对子宫内的细胞,以刺激子宫收缩,如分娩,还针对哺乳母亲乳房中的细胞,以刺激乳液衰竭。

    Summary
    ::摘要

    • The pituitary gland is the master gland of the endocrine system, because most of its hormones control other endocrine glands.
      ::垂体腺是内分泌系统的主腺,因为大部分荷尔蒙控制着其他内分泌腺。
    • The pituitary gland is at the base of the brain, where it is connected to the hypothalamus by nerves and capillaries. It has an anterior (front) lobe that synthesizes and secretes pituitary hormones and a posterior (back) lobe that stores and secretes hormones from the hypothalamus.
      ::脑部底部是脑部的垂体腺,神经和刺青将它与皮下脑膜连接起来。它有一个前额(前额)叶子,可以合成和分泌垂体荷尔蒙和后部(后部)叶子,可以储存和分泌皮下脑荷尔蒙。
    • Hormones synthesized and secreted by the anterior pituitary include growth hormone — which stimulates cell growth throughout the body — and thyroid stimulating hormone (TSH), which stimulates the thyroid gland to secrete its hormones.
      ::由前脑垂体合成和秘密的荷尔蒙包括生长激素——它刺激整个身体细胞生长——和甲状腺刺激激素(TSH),它刺激甲状腺腺分泌其荷尔蒙。
    • Hypothalamic hormones stored and secreted by the posterior pituitary gland include vasopressin — which helps maintain homeostasis in body water — and oxytocin, which stimulates uterine contractions during birth, as well as the letdown of milk during lactation.
      ::后脑垂体腺储存和隐蔽的假体荷尔蒙包括血管压抑剂(有助于保持身体水中的软体保持)和催产素(刺激分娩期间的子宫萎缩),以及哺乳期的牛奶衰竭。

    Review
    ::回顾

    1. Explain why the pituitary gland is called the master gland of the endocrine system.
    ::1. 解释为什么脑下腺被称为内分泌系统的主腺。

    2. Compare and contrast the two lobes of the pituitary gland and their general functions.
    ::2. 比较和比较脑下腺的两个叶及其一般功能。

    3. Identify two hormones released by the anterior pituitary, their targets, and their effects.
    ::3. 查明前脑垂体释放的两种荷尔蒙、其目标及其影响。

    4. Explain how the hypothalamus influences the output of hormones by the anterior lobe of the pituitary gland.
    ::4. 解释下脑瘤如何影响脑下脑腺前额叶的荷尔蒙输出。

    5. Name and give the function of two hypothalamic hormones released by the posterior pituitary gland.
    ::5. 命名和说明后垂垂垂体释放的两种低脑荷尔蒙的功能。

    6. True or False:  The pituitary gland only secretes hormones that are involved in reproduction.
    ::6. 真实的或假的:脑垂体只有分泌与生殖有关的荷尔蒙。

    7. True or False:  The brain does not produce hormones. Only glands produce hormones.
    ::7. 真实或假:大脑不产生荷尔蒙,只有腺产生荷尔蒙。

    8. If a releasing hormone is secreted from the hypothalamus to the pituitary gland, which part of the pituitary receives it? Explain your answer.
    ::8. 如果释放的荷尔蒙从下脑膜到垂垂体腺秘而不宣,哪个部位会得到?解释你的答复。

    9. Answer the following questions about prolactin releasing hormone (PRH) and prolactin inhibiting hormone (PIH).
    ::9. 回答以下关于蛋白质释放激素(PRH)和抑制激素(PIH)的问题。

    a. Where are these hormones produced?
    ::a. 这些荷尔蒙是在哪里生产的?

    b. Where are their target cells located?
    ::b. 其目标细胞的位置在哪里?

    c. What are their effects on their target cells?
    ::c. 它们对其目标细胞有何影响?

    d. What are their ultimate effects on milk production? Explain your answer.
    ::d. 它们对牛奶生产的最终影响是什么?解释你的答复。

    e. When a baby nurses, which of these hormones is most likely released in the mother? Explain your answer.
    ::e. 当一名婴儿护士,其中哪一种荷尔蒙最有可能在母亲体内释放?解释你的答复。

     

    10. For each of the following hormones, state whether it is synthesized in the pituitary or the hypothalamus.
    ::10. 对于以下每一种荷尔蒙,请说明它是在垂体内合成的,还是在下脑膜内合成的。

    a. gonadotropin releasing hormone (GnRH)
    ::a. 遗传释放激素(GNRH)

    b. growth hormone (GH)
    ::b. 生长激素(GH)

    c. oxytocin
    ::c. 催产素

    d. adrenocorticotropic hormone (ACTH)
    ::d. 肾上腺分泌激素(ACTH)

    Explore More
    ::探索更多

    Because the pituitary gland controls the entire endocrine system, disorders of the pituitary can affect virtually any body system. The most common pituitary disorders are pituitary tumors. You can learn about pituitary tumors by watching these brief, interesting videos:
    ::因为垂体腺控制着整个内分泌系统, 垂体紊乱几乎可以影响任何身体系统。 最常见的垂体紊乱是脑肿瘤。 您可以通过观看这些简短有趣的视频来了解垂体肿瘤: