Testes

By Lisa Chiffolo and Mariana Rojas

The Testes: Physically

~The testis is usually between 1.57 inches to 2.75 inches long and 0.8 to 1.2 inches in diameter

~it usually weighs about 25 grams~the testis is oval or egg-shaped~After 7 months in the womb, the testes usually

descend outside the body and are protected by the scrotum (located in the anterior inguinal region)

~The scrotum keeps the testes temperature 2˚C below normal body temperature to allow normal sperm production

Male gonads are composed of numerous coiled seminiferous tubules (where spermatogenesis occurs)

Leydig cells in the testes are dispersed amoung the seminiferous tubules and produce androgens when stimulated by LH from the pituitary gland

Inside the testes there are also Sertoli cells which produce inhibin and take part in spermatogenesis when activated by FSH

Structure of the Testes

The Testes: Chemically

~hypothalamic-pituitary-testes axis: the hypothalamus releases gonadotropin-releasing hormone (GnRH). This stimulates the pituitary gland to release luteinizing hormone (LH) and follicle-stimulating hormone (ACTH) which stimulate the production of testosterone.

~testosterone is an anabolic steroid

The Functions

~The testis produces 12 trillion sperm over the span of one man’s life.

~The job of testes is to produce androgens (male sex hormone) and sperm

~The most important androgen is testosterone in males

~Testosterone helps the reproductive organs grow and mature during puberty*deepens the voice, makes facial hair grow, develops heavy muscles and bones, and allows sperm production*

Hypothalamus and Pituitary Interaction with Testes

The hypothalamus sends GnRH to command the pituitary to release FSH and LH.

Testes make testosterone after the pituitary sends FSH and LH as stimulation.

This process is regulated by negative feedback because after the testes are stimulated they release inhibin and testosterone which signals the hypothalamus and pituitary glands to end their hormone production.

Testicular Torsion

The twisting of the spermatic cord, which cuts off the blood supply to the testicle and surrounding structures within the scrotum

Causes and Symptoms

Torsion can result from “bell clapper” deformity, or trauma if swelling occurs

Symptoms include severe pain in one testicle, scrotal swelling, nausea or vomiting, and light-headedness

Diagnosis, Treatment, and Prevention

This condition is common in infancy and the beginning of adolescence

Ultrasound techniques are used to assess blood flow to testicle

Certain X-ray tests may be used As treatment, surgery should be performed as soon

as possible after symptoms begin If the blood flow is impaired for 6 hours, the testicle

will atrophy and die, and will have to be removed Use precautions to avoid trauma to the scrotum Many cases are not preventable

Hypogonadism

A disorder in which the testicles do not produce enough testosterone, a hormone that play a key role in masculine growth and development during puberty

Causes

Causes of primary hypogonadism are Klinefelter’s syndrome, undescended testicles, hemochromatosis, testicular trauma, cancer treatment, and mumps orchitis

Causes of secondary hypogonadism are Kallmann syndrome, normal aging, pituitary disorders, medications, HIV/AIDS, obesity, and inflammatory disease

Symptoms

Symptoms in fetal development include female genitals, ambiguous genitals, or underdeveloped male genitals

Symptoms in puberty include decreased development of muscle mass, lack of deepening of the voice, impaired growth of the penis, testicles, and body hair, excessive growth of the arms and legs in relation to the trunk, and gynecomastia

Symptoms in adulthood include erectile dysfunction, infertility, decrease in muscle mass and body hair growth, gynecomastia, osteoporosis, fatigue, decreased sex drive, difficulty concentration, and hot flashes

Diagnosis, Treatment, and Prevention

Tests such as hormone testing, semen analysis, pituitary imaging, genetic studies, and testicular biopsies are done to determine if one has primary or secondary hypogonadism

Treatment for hypogonadism depends on the cause Treatment for adults includes hormone replacement

(TRT), surgery, and medication Treatment for boys is Testosterone Replacement

Therapy (TRT) by injection, patch, gel, gum and cheek, and oral methods

Hypogonadism is not preventable

Orchitis

A condition involving inflammation, swelling, and frequent infection of one or both of the testicles

Causes and Symptoms

Causes of bacterial orchitis include epididymitis and STDs

Cause of viral orchitis is most likely the mumps

Symptoms include testicular swelling and tenderness, pain, nausea, fever, discharge from penis, and blood in the ejaculate

Diagnosis, Treatment, and Prevention

Tests such as STD screening, urinalysis, ultrasound imaging, and nuclear scans of the testicles are done to reach a diagnosis

Treatment depends on the cause of orchitis Treatment for bacterial orchitis includes antibiotics Treatment for viral orchitis includes pain medication,

anti-inflammatory drugs, and bed rest Safer sex behaviors will decrease chances of

developing STD-related bacterial orchitis Getting vaccinated against mumps will prevent

mumps-related viral orchitis

Works Cited

http://www.innerbody.com/image_endoov/repo10-new2.html http://www.emedicinehealth.com/

understanding_the_male_anatomy/page4_em.htm#Testes/Testicles

http://www.britannica.com/EBchecked/topic/588769/testis http://www.home-remedies-for-you.com/askquestion/68329/

human-testicle-size-i-have-age-of-18-male-i-have-d.html Campbell and Reese. “Biology: Ninth Edition”. 2010. Benjamin

Cummings. 1005-1006. http://urologyhealth.org/adult/index.cfm?cat=11&topic=134 http://catalog.nucleusinc.com/generateexhibit.php?ID=8364 http://www.urologyhealth.org/picturepopup.cfm?id=57 http://my.clevelandclinic.org/disorders/testicular_cancer/hic_diso

rders_of_the_testes.aspx http://www.mayoclinic.com/health/male-hypogonadism/DS00300 http://www.urologyhealth.org/adult/index.cfm?cat

=11&topic=671

Works Cited (continued)

http://www.endotext.org/male/male5/maleframe5.htm

http://www.healthtree.com/articles/testosterone/deficiency/

http://www.cjurology.com/epi.html http://radiology.rsna.org/content/217/1/219/F21.exp

ansion http://www.webpathology.com/image.asp?case

=29&n=3 http://www.mayoclinic.com/health/orchitis/DS00602 http://www.nlm.nih.gov/medlineplus/ency/article/001

280.htm

Works Cited (Pictures)

o http://www.cancer-concerns.com/TEST/test1.htmo http://www.webpathology.com/image.asp?case=28&n=2o http://www.webpathology.com/image.asp?case=28&n=1 o http://www.ceessentials.net/article42.htmlo http://courses.washington.edu/chordate/453photos/uroge

nital_photos/mammal_urogenital_photo.htmo http://www.wetdreamforum.com/wd/male_anatomy.htmo http://www.urology-textbook.com/male-hormones-

testosterone.htmlo http://www.soc.ucsb.edu/sexinfo/article/the-testes o http://bio1151.nicerweb.com/Locked/media/ch46/

androgens.html http://drugster.info/ail/pathography/399/ http://radiology.rsna.org/content/217/1/219/F6.expansion