Yyyy Male Reproductive Hormones

Front 1

____ stimulates spermatogenesis. ___ is under the control of GnRH

Back 1

follicle-stimulating hormone

Front 2

_____stimulates production of testosterone. _______ is under the control of GnRH

Back 2

luteinizing hormone

Front 3

Sperm are formed from stem cells called

Back 3

spermatogonia

Front 4

are polyfunctional cells that aid in the development and maturation of sperm

Back 4

Sertoli cells

Front 5

• is the principal male sex hormone and is secreted by the testes (and to a much lesser extent by the adrenal glands and ovaries).

• promotes development and maintains the male reproductive system.

• It is responsible for development and maintenance of secondary male sex characteristics (e.g., facial and body hair, muscle development).

Back 5

Testosterone

Front 6

• In adult males, there are no observable symptoms.

• In prepubertal males, precocious puberty occurs (may be caused by hypothalamic tumors, congenital adrenal hyperplasia, testicular tumor).

• In female children, development of male secondary sex characteristics/virilization occurs (increased androgen production by ovaries or adrenals as androgens are estrogen precursors in females)

Back 6

Hyperandrogenemia

Front 7

- is caused by an enzymedefect of 21- hydroxylase, which prevents Cortisol production and results in accumulation of Cortisol precursors, including 17-ahydroxyprogesterone (17-OHP).

- CAH is characterized by increased blood levels of 17-OHP and ACTH and decreased Cortiso

Back 7

Congenital adrenal hyperplasia (CAH)

Front 8

• In adult males, impotence and loss of secondary sex characteristics occurs; in prepubertal males, delayed puberty results.

Back 8

Hypoandrogenemia

Front 9

: - Causes include infections, tumors, congenital disorders (Klinefelter syndrome)

Back 9

Primary hypoandrogenemia

Front 10

: Male possesses an extra X chromosome (XXY). Characteristics include tall with long extremities, small testes, gynecomastia, infertility, and low IQ

Back 10

Klinefelter syndrome

Front 11

: Causes include primary hypofunction disorders of the pituitary or hypothalamus, which in turn cause decreased synthesis of LH and FSH

Back 11

Secondary hypoandrogenemia

Front 12

is the most severe form of androgen resistance syndrome, resulting from mutations of the androgen receptor and impaired androgen actions in target tissues.

• As a result of the lack of androgen and unopposed estrogen effects, the physical development pursues the female phenotype, with fully developed breast and female distribution of fat and hair

Back 12

Testicular feminization syndrome

Front 13

Deficiency of _______ is a rare cause of androgen insensitivity and results in a mutation encoding the type 2 isoenzyme, maps to chromosome 2p23, and is expressed in XY males

Back 13

5α-reductase

Front 14

(type 1 caused by DMPK gene mutation and type 2 caused by CNBP gene mutation) is inherited in an autosomal dominant fashion (almost always, an affected person has one parent with the condition) and presents with primary hypogonadism, frontal balding, diabetes, and muscle weakness, atrophy, and dystonia (an inability of the muscle to relax adequately after contraction)

Back 14

Myotonic dystrophy

Front 15

develops in a third of postpubertal males with mumps and is the most frequent extrasalivary manifestation of this highly contagious infection

Back 15

Mumps orchitis

Front 16

is characterized by a lack of germ cells.

• Men present with small testes, high FSH levels, azoospermia, and normal testosterone levels.

• Testicular biopsy, which is necessary for diagnosis, shows lack (or complete absence) of spermatozoa.

• This disorder may arise from Y chromosome microdeletions on Yq11 locus (AZF region: Azoospermia Factor).

• It is relatively rare, affecting 5% to 10% of all infertile men in the country

Back 16

Sertoli cell–only syndrome (SCO syndrome or germ cell aplasia)

Front 17

Mutations in the KAL1 gene (a gene found on the X chromosome) occur less often in sporadic cases (<10%).

• In general, the clinical phenotypes of idiopathic hypogonadotropic hypogonadism (IHH) subjects with KAL1 mutations are characterized with a high incidence of microphallus, cryptorchidism, and small testes

Back 17

Kallmann's Syndrome

Front 18

The impaired secretion of GnRH has been elucidated in the X-linked form of congenital GnRH deficiency, which results from impaired migration of GnRH neurons and olfactory nerves to the ventral hypothalamus during embryogenesis.

• Proper migration of these neurons is dependent on the correct expression of anosmin, a 680–amino acid neural cell adhesion molecule–like protein, which is the product of the KAL1 gene.

Back 18

Kallmann's Syndrome

Front 19

is a result of an inherited, X-linked recessive trait that manifests as hypogonadism during puberty.

• The frequency of this syndrome is 1 of 10,000 males

Back 19

Kallmann's syndrome