Question

Fill in the blanks?
Ovulation is induced by the hormone called _____________.

Answer 1

Hint: Ovulation is a physiological process characterized by the rupture and release into the fallopian tube of the ovarian follicle from the ovary where it has the potential to become fertilized.

Complete answer:
When the estrogen level is high enough, it induces a sudden release of LH, normally about thirteen days of the cycle. This LH surge (peak) causes a complex series of egg-extrusion events inside the follicles that result in the final maturation of the egg and follicular collapse. Ovulation occurs 28-36 hours after the LH surge begins and 10-12 hours after LH hits its peak. The cells that are left behind after ovulation undergo a process in the ovarian follicle to become the called corpus luteum. They now contain large levels of progesterone, in addition to estrogen, to prepare the uterus lining for implantation.

The ovulation mechanism is regulated by the brain's hypothalamus and by releasing hormones that are secreted in the anterior lobe of the pituitary gland are luteinizing hormone (LH) and follicle-stimulating hormone (FSH).

Additional information:
Hormones influencing ovulation include:
1. Gonadotropin-releasing hormone (GnRH) is a hormone produced and secreted by the hypothalamus of a tropical peptide. It is a releasing hormone which stimulates the release of FSH and LH from the anterior pituitary gland via pulse frequency variations in GnRH.

2. Gonadotropin hormones are glycoproteins with alpha/beta subunits which are heterodimeric. Both glycoproteins including TSH (thyroid-stimulating hormone) and HCG (human chorionic gonadotropin hormone) are abundant in the alpha subunit.

The relationship between FSH and LH hormones is essential for the process which induces follicular growth, rupture, release, and receipt or shedding of the endometrial layer.

> Follicle-Stimulating Hormone (FSH) is a synthesized gonadotropin that is secreted from the anterior pituitary gland in response to pulsatile slow-frequency GnRH. The FSH induces the development and maturation of immature oocytes before ovulation into mature (Graafian) secondary follicles.

> Estrogen is a steroid hormone responsible for the development and control of the female reproductive system and the characteristics of the secondary sex. Estrogen also has many other effects in premenopausal patients which are critical for bone health and cardiovascular health.

> Luteinizing Hormone (LH) is a gonadotropin synthesized and secreted in response to the high-frequency release of GnRH by the anterior pituitary gland. LH is responsible for ovulation-inducing, preparation for fertilized uterine oocyte implantation, and ovarian progesterone development by stimulation of theca cells and luteinized granulosa cells.

> Progesterone is a steroid hormone that is responsible for arranging the endometrium for fertilized egg uterine implantation and pregnancy maintenance. If a fertilized egg implants, progesterone is secreted by the corpus luteum in early pregnancy before the placenta grows and takes over the development of progesterone for the remainder of the pregnancy.

Note: Disruption in hormonal contact between the GnRH and gonadotropic hormones and their receptors can result in anovulation or amenorrhea resulting in different pathological complications.