Male Repro III

Question 1

Efferent ductules

Answer 1

-lined by simple columnar epithelium with ciliated (help move sperm) and non-ciliated cells (absorb 90% and digest duct fluid)

Question 2

Epididymis

Answer 2

-lined by pseudostratified columnar epithelium with stereocilia (shorter towards tail) for reabsorption

-surrounded by circular smooth muscle fibers. Increase in thickness from head to tail

-principal cells (taller in head than body/tail) for reabsorption and secretory.

Question 3

Depletion of sperm reserve in tail

Answer 3

-frequent sequential ejaculations will deplete spermatozoal reserves in distal tail of epididymis

Question 4

Male accessory sex glands

Answer 4

-ampulla
-vesicular glands
-prostate glands
-Bulbourethral gland

**testosterone dependent and wil shrink in castrated animals (especially vesicular glands)

Question 5

Ampulla

Answer 5

-terminal part of ductus deferens with many pockets
-glandular
-opens into pelvic urethra

**ruminants and stallion

Question 6

Vesicular glands

Answer 6

-lined by pseudostratified secretary columnar epithelium and basal cells

-empties into pelvic urethra

**bulls and boar; important for ejaculate
**not in cats

Question 7

What does vesicular glands produce?

Answer 7

-produces white/yellow gelatinous secretion rich in fructose

Question 8

Prostate gland

Answer 8

-contributes to ejaculate:
>boars 35-60%, stallions 25-30%, ruminants 4-6%
- body/compact/external portion surrounds pelvic urethra
-disseminate/internal portion

Question 9

Prostate gland secretion

Answer 9

-serous and some mucus secretion
-neutralizes seminal plasma by making it acidic by accumulation of CO2
-initiated active movement of sperm

Question 10

Bulbourethral gland

Answer 10

-mucous and proteinaceous secretion discharged before ejaculation. Neutralizes urethral environment, lubricates urethra and vagina
>Cat-mucous material also has glycogen acting as energy source in seminal plasma (important because they don’t have vesicular glands with fructose)
>boar- mucous material with sialic acid which may occlude cervix to prevent sperm loss

**absent in dog, developed in boar

Question 11

Flehman response and vomeronasal organ

Answer 11

-Flehman- curling of lip so airflow through nasal passage is restricted. Results in sub-atmospheric pressure in nasopalatine duct

-pressure allows fluid to be aspirated into duct and into sensory surface of vomeronasal organ

-special epithelium of vomeronasal organ can sense pheromones

Question 12

Anatomy of erection

Answer 12

-Has 2 corpus cavernosa and a corpus spongiosum

-corporal sinusoids supplied by helicine arteries
-Arterial blood=dorsal and cavernosal arteries
-Drain blood= deep or superficial dorsal vein

Question 13

Penis differences in horse, ruminants, dogs

Answer 13

Horse: has corporal sinusoids

Dogs: os penis

Ruminants: more fibrous penis

Question 14

Flaccid penis

Answer 14

-sinusoids are flat due to NE release from adrenergic nerves causing constriction resulting in low blood flow to cavernous tissue

-no stimulation from erotogenic stimuli, nonadrenergic noncholinergic parasympathetic neurons do not fire and release NO = vasoconstriction

Question 15

Erect penis

Answer 15

1. When erotogenic stimuli is present, NANC neurons fire and release NO.
2. NO activates guanylate cyclase converting GTP to cGMP
   3.causes relaxation of smooth muscle of corporal sinusoids (vasodilation)
3. leads to the engorement of cavernous sinusoids with blood and intracorporal pressure increases fast
4. Increased pressure=compresses venules= trapping blood in penis=erection