26 Role of Hormones in the Male. Taft College Human Physiology

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1 26 Role of Hormones in the Male Taft College Human Physiology

2 The Role of Hormones in the Male Testes function to produce: 1. Spermatozoa (seminiferous tubules) 2. Source of male hormones. Collectively known as androgens produced in interstitial cells. The principle androgen = testosterone.

3 Functions of Androgens (Testosterone and DHT (dihydrotestosterone)) Androgen = a male sex hormone that promotes the development and maintenance of the male sex characteristics. The major androgen is testosterone. 1. Development of Sex Organs In fetus important in development of external sex organs and descent of testes. At puberty enlargement of penis, testis, prostate gland, & seminal vesicles

4 Functions of Androgens (Testosterone and DHT (dihydrotestosterone)) 2. Development of Secondary Sexual Characteristics Androgens also effect body parts not included in sperm production therefore they are called secondary sex characteristics. Secondary sex characteristics are features not directly involved with reproduction. Secondary Sexual Characteristics a. Growth of beard and body hair. b. Growth of larynx- deepening of the voice. c. Skeletal and muscular size. d. Stimulates sweat glands- increases production of sweat. e. Stimulates oil secreting sebaceous glands overproduction acne.

5 Functions of Androgens (Testosterone and DHT (dihydrotestosterone)) 3. Sexual functions Spermatogenesis Contributes to sex drive (libido). In females too! From adrenal cortex. 4. Metabolism Androgens are anabolic steroids that promote protein synthesis. This creates more muscle and bone mass. Stimulates closure of epiphyseal plates.

6 Regulation of Hormone Production on the Male Production of testosterone is regulated by gonadotropic hormone lcsh. ICSH = interstitial cell stimulating hormone in males and is the same hormone as LH (luteinizing hormone) in females. The ICSH from the pituitary signals the interstitial cells to produce testosterone.

7 Prostaglandins Prostaglandins are potent fatty acids that act as local hormones. Originally thought to be produced in prostate ( prosta ) but later shown to be produced in the seminal vesicles.

8 Prostaglandins Prostaglandins have hormone-like qualities but differ in 5 important ways. 1. They are fatty acids - no other hormones are. 2. Target organ may be in individual that produces prostaglandin or may affect another individual (passed in semen). 3. Travel through genital ducts instead of blood stream. They cause local effects during reproduction activities. Found throughout the body but are produced and act locally (paracrine, autocrine) instead of distribution through the bloodstream. 4. Produce marked effects in extremely low concentrations. 5. Produced by cell membrane from phospholipids instead of cytoplasm

9 Effect of Prostaglandins in Reproduction Prostaglandins have many effects in the body blood, flow, platelet function, inflammation mediation, pain intensity and others. We will focus on smooth muscle contraction in the reproductive system. Semen with prostaglandin causes contractions in uterus and oviducts of female, therefore assisting sperm in route to oviduct and oocyte to the uterus. Females have prostaglandins as well (trigger the muscles of the womb to expel the lining). The semen of some infertile men has been shown to be low in prostaglandins. Some infertile women have been shown to be unresponsive to prostaglandins.

10 Effect of Prostaglandins in Reproduction Prostaglandins are found in the menstrual flow of females. Females with severe menstrual cramps (dysmennorhea) have shown 2-3 times the normal amount of prostaglandins. An increase in prostaglandins causes stronger contractions of the myometrium (muscular wall of the uterus) and more rapid contractions. This leads to decreased blood supply of the area, decreased O 2 and therefore cramps.

11 Effect of Prostaglandins in Reproduction Prostaglandins produced by the placenta contribute significantly to labor by stimulating contraction in the uterus and reinforcing oxytocin release. Taking aspirin like drugs may inhibit onset of labor. Aspirin inhibits prostaglandin activity by interfering with a key enzyme in its synthesis.

12 is really a beetle! Aphrodisiac food, drug, scent or other agent that increases sexual desire. Although many aphrodisiacs have been suggested it is the consensus of most biologists that none have been proven effective. Aphrodisiacs Spanish fly

13 Aphrodisiacs Some examples: pine nuts, the blood of bats mixed with donkeys milk, root of the valerian plant, dried salamander, air, menstrual fluid. tulip bulbs, fat of a camel's hump, parsnips, salted crocodile, pollen of a date palm, the powdered tooth from a corpse, wings of bees, jasmine, henna (externally applied), ground crickets, spiders or ants, the genitals of hedgehogs, rhinoceros horn, the blood of executed criminals, artichokes, honey compounded with camels milk, swallow's hearts, vineyard snails, certain bones of a toad, powdered stag horn, peanut butter, root beer, scrapings from the ear of a raccoon, oysters, ginseng, chocolate, sex organs of rabbits and goats, licorice, sea turtle eggs. You name it It s been suggested! Despite the motivation to find something... anything!!! no scientific evidence exists to support claims of increased libido.

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15 The End Congratulations, and thank you for your hard work this semester. Thank you for attending Taft College!!! Please keep us informed of your success, acceptance letters, graduations, passing the boards a new house with lots of room in Hawaii- or if you need help celebrating your lottery winnings!