luteinizing hormone

Examples of luteinizing hormone in the following topics:

• Hormonal Regulation of the Male Reproductive System

  • Hormonal control of spermatogenesis varies among species.
  • They are capable of producing the hormones estradiol and inhibin.
  • There it stimulates the synthesis and secretion of the gonadotropins, FSH and luteinizing hormone (LH).
  • Follicle Stimulating Hormone is released by the anterior pituitary gland.
  • Luteinizing Hormone is released by the anterior pituitary gland.

• Onset, Duration, and Half-Life of Hormone Activity

  • Hormone half-life and duration of activity are limited and vary from hormone to hormone.
  • Hormone half-life and duration of activity are limited and vary from hormone to hormone.
  • Duration of hormone activity refers to the duration of events which were stimulated by hormone-receptor binding.
  • Follicle-Stimulating Hormone 2.
  • Luteinizing Hormone 4.

• Hormonal Regulation of the Female Reproductive Cycle

  • The menstrual cycle is controlled by a series of changes in hormone levels, primarily estrogen and progesterone.
  • Follicle-stimulating hormone (FSH) is secreted by the anterior pituitary gland.
  • Follicle-stimulating hormone induces the proliferation of granulosa cells in the developing follicles and the expression of luteinizing hormone (LH) receptors on these cells.
  • Luteinizing hormone induces androgen synthesis by theca cells, stimulates proliferation, differentiation, and increases LH receptor expression on granulosa cells.
  • The surge also initiates luteinization of theca and granulosa cells.

• The Anterior Pituitary

  • Thyroid-stimulating hormone is a glycoprotein hormone that affects the thyroid gland and the secretion of thyroid hormones.
  • Follicle-stimulating hormone is a glycoprotein hormone that targets the gonads and effects the growth of the reproductive system.
  • Luteinizing hormone is a glycoprotein hormone that targets the gonads to effect sex hormone production.
  • Growth hormone is a polypeptide hormone that targets the liver and adipose tissue, which promotes growth through lipid and carbohydrate metabolism.
  • Hormone secretion from the anterior pituitary gland is regulated by hormones secreted by the hypothalamus.

• Male Hormones

  • The onset of puberty is controlled by two major hormones: FSH initiates spermatogenesis and LH signals the release of testosterone.
  • These changes are largely influenced by hormonal activity.
  • Hormones play an organizational role, priming the body to behave in a certain way once puberty begins, and an activational role, referring to changes in hormones during adolescence that trigger behavioral and physical changes.
  • At the onset of puberty, the hypothalamus begins secreting high pulses of GnRH, or gonadotropin-releasing hormone.
  • In response, the pituitary gland releases follicle stimulating hormone (FSH) and luteinizing hormone (LH) into the male system for the first time.

• Hypothalamic-Pituitary Axis

  • The anterior pituitary produces seven hormones: growth hormone (GH), prolactin (PRL), thyroid-stimulating hormone (TSH), melanin-stimulating hormone (MSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH).
  • Anterior pituitary hormones are sometimes referred to as tropic hormones because they control the functioning of other organs.
  • While these hormones are produced by the anterior pituitary, their production is controlled by regulatory hormones produced by the hypothalamus.
  • These regulatory hormones can be releasing hormones or inhibiting hormones, causing more or less of the anterior pituitary hormones to be secreted.
  • Negative feedback then regulates how much of these regulatory hormones are released and how much anterior pituitary hormone is secreted.

• Hormonal Regulation of the Reproductive System

  • During puberty, in both males and females, the hypothalamus produces gonadotropin-releasing hormone (GnRH), which stimulates the production and release of follicle stimulating hormone (FSH) and luteinizing hormone (LH) from the anterior pituitary gland.
  • FSH production is inhibited by the hormone inhibin, which is released by the testes.
  • It is also called interstitial-cell-stimulating hormone.
  • Prolactin levels are regulated by the hypothalamic hormones, prolactin-releasing hormone (PRH) and prolactin-inhibiting hormone (PIH) (which is now known to be dopamine).
  • Hormonal regulation of the female reproductive system involves hormones from the hypothalamus, pituitary, and ovaries.

• Hormonal Methods

  • Hormonal birth control contains steroid hormones that alter female fertility.
  • Altogether, 18% of the world's contraceptive users rely on hormonal methods.
  • Hormonal contraception is highly effective: when taken on the prescribed schedule, users of steroid hormone methods experience pregnancy rates of less than 1% per year.
  • The effect of hormonal agents on the reproductive system is complex.
  • Progesterone negative feedback decreases the frequency of gonadotropin-releasing hormone (GnRH) released by the hypothalamus, which decreases the release of follicle-stimulating hormone (FSH), and greatly decreases the release of luteinizing hormone (LH) by the anterior pituitary.

• Female Hormones

  • The stages of the ovarian cycle in the female are regulated by hormones secreted by the hypothalamus, pituitary, and the ovaries.
  • As with the male, the hypothalamic hormone GnRH (gonadotropin-releasing hormone) causes the release of the hormones FSH (follicle stimulating hormone) and LH (luteinizing hormone) from the anterior pituitary.
  • Follicle cells produce the hormone inhibin, which inhibits FSH production.
  • Estradiol and progesterone are steroid hormones that prepare the body for pregnancy.
  • Rising and falling hormone levels result in progression of the ovarian and menstrual cycles.

• Ovarian Cycle

  • The main hormone controlling this stage is estradiol.
  • During the follicular phase, follicle-stimulating hormone (FSH) is secreted by the anterior pituitary gland.
  • Follicle-stimulating hormone induces the proliferation of granulosa cells in the developing follicles, and the expression of luteinizing hormone (LH) receptors on these granulosa cells.
  • These falling levels of ovarian hormones cause increased levels of FSH, which begins recruiting follicles for the next cycle.
  • Because the hormone is unique to the embryo, most pregnancy tests look for the presence of hCG.