Hormone

Hormone

Created by:Nuzulul Rahmawati (083194002)

Dedy Agus S (083194004)

Erika Aprillia (083194033)

Introduction

• A hormone is a chemical that is released into the blood by one organ and carried to another part of the body, where it causes a particular response by a particular kind of tissue.

• Although hormones in the blood reach all the cells in the body, they affect only specific cells, their target cells.

• Currently, there are about 50 known human hormones.

• Some Of them are Glucagon, FSH and Testosterone.

Follicle stimulating hormone (FSH)

• Follicle stimulating hormone (FSH) is synthesized and secreted by gonadotroph of the anterior pituitary gland.

• It can found in humans and other animals. FSH regulates the development, growth, pubertal maturation, and reproductive processes of the body.

FSH structure • FSH is a glycoprotein. Each monomeric unit is a

protein molecule with a sugar attached to it. Two of these make the full, functional protein. Its structure is similar to those of LH, TSH, and hCG. The protein dimer contains of 2 polypeptide units, labeled alpha and beta subunits.

• The alpha subunit of LH, FSH, TSH, and hCG are identical, and contain 92 amino acid.

• The beta subunits have varian. FSH has a beta subunit of 118 amino acids (FSHB), which confers its specific biologic action and is responsible for interaction with the FSH-receptor.

The Effects of FSH activities in females

• FSH stimulates the growth and recruitment of immatur ovarian follicles in the ovary. In early antral follicles, FSH is the major survival factor that rescues the follicles from apoptosis. In the luteal-follicle phase transition period the serum levels of progesterone and estrogen decrease and no longer suppress the release of FSH, consequently FSH peaks at about day three (day one is the first day of menstrual flow). The cohort of small antral follicles is normally sufficiently in number to produce enough inhibinB to lower FSH serum levels.

• When the follicle matures and reaches 8–10 mm in diameter it starts to secrete significant amounts of estradiol. The sharp increase in estradiol production by the dominant follicle (possibly along with a decrease in gonadotrophin surge-attenuating factor) cause a positive effect on the hypothalamus and pituitary and rapid GnRH pulses occur and an LH surge results.

• The increase in serum estradiol levels cause a decrease in FSH production by inhibiting GnRH production in the hypothalamus.

• The decrease in serum FSH level causes the smaller follicles in the current cohort to undergo atresia as they lack sufficient sensitivity to FSH to survive. Occasionally two follicles reach the 10 mm stage at the same time by chance and as both are equally sensitive to FSH both survive and grow in the low FSH environment and thus two ovulations can occur in one cycle possibly leading to non identical twins.

The Effects of FSH activities in males

FSH stimulates maturation of seminiferous tubules and

spermatogenesis.

FSH enhances the production of androgen binding protein by the sertoli cells of the teste by binding to FSH receptor on their basoteral membranes, and is critical for the initiation of spermatogenesis.

The Effect Of High FSH Levels

If high FSH levels occur during the reproductive years, it is abnormal.

Conditions with high FSH levels include:

• Premature menopause also known as Premature Ovarian Failure

• Poor ovarian reserve also known as Premature Ovarian Aging

• Testicular failure.

Most of these conditions are associated with subfertility and/or infertility. Therefore high FSH levels are an indication of subfertility and/or infertility.

The Effect Of Low FSH levels

• Conditions with very low FSH secretions are:

• Polycystic Ovarian Syndrome

• Polycystic Ovarian Syndrome + Obesity + Hirsutism + Infertility

• Kallmann syndrome

• Hypothalamic suppression

• Hypopituitarism

• Hyperprolactinemia

• Gonadotropin deficiency

• Gonadal suppression therapy

• GnRH antagonist

• GnRH agonist (downregulation).

GLUCAGON HORMONE

Description

• Glucagon is a hormone, secreted by the pancreas, that raises blood glucose levels. Its effect is opposite that of insulin, which lowers blood glucose levels.

FUNCTION

• Glucagon helps maintain the level of glucosein the blood.

• Glucagon also regulates the rate of glucose production through lipolysis.

STRUCTURE

• Glucagon is a 29-amino acid polypeptide. Its primary structure in humans is:

• NH2-His-Ser-Gln-Gly-Thr-Phe-Thr-Ser-Asp-Tyr-Ser-Lys-Tyr-Leu-Asp-Ser- Arg-Arg-Ala-Gln-Asp-Phe-Val-Gln-Trp-Leu- Met-Asn-Thr-COOH.

REGULATION MECHANISM

• Increased secretion of glucagon is caused by:

• Decreased plasma glucose

• Increased catecholamines - norepinephrine and epinephrine

• Increased plasma amino acids (to protect from hypoglycemia if an all-protein meal is consumed)

• Sympathetic nervous system

• Acetylcholine

• Cholecystokinin

• Decreased secretion (inhibition) of glucagon is caused by:

• Somatostatin

• Insulin

• Increased free fatty acids and ketoacids into the blood

• Increased urea production

TESTOSTERONE

• Testosterone is a steroid hormone

• In men, testosterone plays a key role in the development of male reproductive tissues such as the testis and prostate as well as promoting secondary sexual characteristics such as increased muscle, bone mass and hair growth. In addition, testosterone is essential for health and well-being as well as the prevention of osteoporosis.

CHEMICAL STRUCTURE OF TESTOSTERONE

Physiological effects

• Anabolic effects include growth of muscle mass and strength, increased bone density and strength, and stimulation of linear growth and bone maturation.

• Androgenic effects include maturation of the sex organs, particularly the penis and the formation of the scrotum in the fetus, and after birth (usually at puberty) a deepening of the voice, growth of the beard and axillary hair. Many of these fall into the category of male secondary sex characteristics.

PUBERTAL

In males, these are usual late pubertal effects, and occur in women after prolonged periods of heightened levels of free testosterone in the blood. • Enlargement of sebaceous glands. This might cause acne.• Phallic enlargement or clitoromegaly• Increased libido and frequency of erection or clitoral

engorgement• Pubic hair extends to thighs and up toward umbilicus• Facial hair (sideburns, beard, moustache)• Loss of scalp hair (Androgenetic alopecia)• Chest hair, periareolar hair, perianal hair• Leg hair

• Axillary hair• Subcutaneous fat in face decreases• Increased muscle strength and mass• Deepening of voice• Growth of the Adam's apple• Growth of spermatogenic tissue in testicles, male

fertility• Growth of jaw, brow, chin, nose, and remodeling of

facial bone contours• Shoulders become broader and rib cage expands• Completion of bone maturation and termination of

growth. This occurs indirectly via estradiol metabolites and hence more gradually in men than women.

Mechanism of Action