Histology Ch 27. Sweat Gland
How does apocrine sweat look and smell like?
- Cloudy - Viscous fluid - Odorless when freshly secreted.
What does repeated heavy sweating over the course of a week causes the cells of the coiled duct?
- Increase their energy reserves so that they can function throughout the period of sweating - This is called acclimatation.
How does the straight duct of the eccrine sweat gland look like?
- It has a stratified cuboidal epithelium. - Have a cuticular border. - A keratin‑filled apex in the apical cells of the duct epithelium
What happens if one sweats much longer than usual?
- The cells of the coiled duct may run out of glycogen. - It ceases to recover salts from the sweat
What two types of glands open onto the skin surface?
1. eccrine sweat glands 2. apocrine glands
What are the three parts of the eccrine sweat gland?
1.secretory coil 2.the coiled duct 3.the straight duct
The lumen of the secretory coil is rarely more than ________ wide.
10 micrometer
The cooling capacity of acclimatized eccrine sweat glands is enormous. They can produce __________ (more than a liter per hour in the noonday sun)
13 liters of sweat a day
The lumen of the secretory coil of an apocrine gland is large, often measuring about...
60 micro meter across
What would cure hyperthermia?
A cold shower.
What grows from each lactiferous sinus?
A few intralobar ducts with stratified cuboidal epithelium.
What does a lactiferous sinus look like?
A stratified squamous epithelium.
What is the function of the clear cells of the secretory coil?
Actively transport Na+ into the lumen of the secretory coil. NOTE: Water follows the sodium by osmosis.
What is the action of the mucus secreted by an eccrine sweat gland?
Acts as a moisturizer for the stratum corneum
Where do we find Eccrine sweat glands?
All over the body
Where do Ligaments of type I collagen (Cooper's ligaments) develop?
Along the lactiferous sinuses and intralobar ducts.
What are anti‑perspirants based on?
Aluminum chloride or zirconium chloride
Where do stellate myoepithelial cells develop from?
Alveolar cells and surround the alveoli
What is an eccrine sweat gland?
An unbranched tubular gland
Between Eccrine sweat ducts and apocrine ducts which one lacks cuticular border?
Apocrine ducts
Where do mammary glads probably evolved from?
Apocrine glands
Where does the nipple forms?
Around each group of lactiferous sinuses
What is the ideal treatment for a heat stroke?
Bath in ice water with monitoring of rectal temperature.
Why do Sweat stays on the skin surface?
Because the stratum granulosum is waterproof
Where do Myoepithelial cells lie?
Between the cuboidal cells and the basement membrane
What happens to a person during a heat stroke?
Brain damage is likely unless he is cooled promptly
What does the discharge of the granules of the apocrine gland do?
Changes the epithelium from simple columnar to simple cuboidal.
What do the basal cells of the coiled duct transport?
Cl- from the apical cells into the tissue fluid.
The secretory part of the apocrine glands are...
Coiled and branched.
What is the function of the straight duct of the eccrine sweat gland?
Conduit from the coiled duct to the skin surface.
What is the meaning of hypotonic?
Contains less salt than tissue fluid or blood plasma
What is the downside of using sports drink?
Delays acclimatization
If a large area of thick skin is denuded of epidermis, how does healing takes place?
Depends on the dedifferentiation, migration, multiplication, and growth of the cells of the straight ducts of sweat glands.
What does the dark cells of the secretory coil of an eccrine sweat gland secrete?
Dermcidin and mucus
How does the areolar form?
Due to the involution of hair follicles around the nipple forms the areola.
Why does the nipple forms around each group of lactiferous sinuses?
Due to thickening of both epidermis and dermis.
What two types of ducts do the cuticular border distinguishes?
Eccrine sweat ducts from apocrine ducts
What increases the number of glands secreting?
Emotional stress or excitement.
Both types of deodorants: aluminum chloride based and triclosan or paraben based are suspected of?
Endocrine disruptors.
Where do many secretory alveoli develops from?
Ends of the ducts
The secretory cells of apocrine glands accumulate ________ in secretory granules in the apices of the cells.
Glycoproteins and polysaccharides
Thus sweating can dissipate twice as much energy as is contained in a normal day's food! This extra capacity allows for...
Hard labor and heat absorbed from the sun
What does salt loss leads to?
Heat exhaustion
What happens when the patient ceases to sweat?
Heat stroke
Alcohol consumption depresses the temperature control center of the brain and makes one more vulnerable to
Hyperthermia and heat stroke
Normal sweat is....
Hypotonic
The coiled duct is wound up with the secretory coil
Important to know to identify structures.
When do the eccrine sweat glands of the palms and soles secrete?
In response to emotional stress.
When do the eccrine sweat glands of the general body surface secrete?
In response to heat.
Peripheral temperatures do not accurately track core temperature in heat stroke
Interesting
What grows from the lobar ducts?
Intralobular ducts with simple cuboidal epithelium.
What happens if the body is pushed beyond its cooling capacity?
Its temperature rises
13 liters times the heat of vaporization of water (580 kcal/l) is 7540 kcal
Know it
Which ones are the major mammary ducts that grow in from the epidermis at the site of each breast in fetuses of both sexes?
Lactiferous sinuses
The lumen of the apocrine sweat duct in fairly narrow, usually...
Less than 20 micro meters across
What does each lactiferous sins will drain?
Lobe of the mammary gland
What are the basal cells of the coiled duct composed of?
Mitochondria and glycogen
Deodorants based on triclosan or paraben rarely irritate normal skin, but they often irritate....
Mucous membranes
What do deodorants based on aluminum chloride irritate on the skin?
Mucous membranes or chafed skin
How does epidermal wounds usually heal?
Multiplication, growth, and migration of cells from the stratum basale of adjacent intact epidermis.
What can be recovered from the transport of Cl- by the basal cells of the coiled ducts?
Na+, K+ and Ca++ are recovered from the sweat.
Salt tablets are poorly absorbed, and a side effect can be?
Nausea
Where do apocrine glands open?
Next to hair follicles in the armpits and mons pubis.
Where do clear cells and dark cells rest?
On a thick basement membrane.
What is demicidin?
Polypeptide antibiotic that depolarizes bacterial cell membranes.
Because the clear cells of the secretory coil are not as tall as the dark cells, this gives the secretory coil a _______ appearance.
Pseudo-stratified (or the way he wants it: pseudo-stratified cuboidal epithelium)
What does tonic contraction of the myoepithelial cells regulate?
Regulate the width of the lumen of the secretory coil.
What grows from intralobular ducts?
Secretory alveoli with simple cuboidal epithelium.
Apocrine glands are composed of:
Simple columnar or simple cuboidal epithelium.
What does Apocrine sweat nourishes?
Skin bacteria that produce the characteristic odor of the human body
Where are they most densely distributed?
Skin of the palms and soles
An unacclimatized athlete may also need
Sports drink
How does the coiled duct looks like?
Sstratified cuboidal epithelium with 2 layers of cells
The epithelium of the apocrine sweat duct looks like?
Stratified cuboidal epithelium without a cuticular border
What is the Hypodermis?
Subcutaneous fat
What does healing of thin skin depends on?
The bulge of the outer root sheath of hair follicles.
What do phasic contractions of the myoepithelial cells assists in?
The delivery of sweat to the skin surface
Hyperthermia
The eccrine sweat glands continue to sweat.
What do anti‑perspirants cause?
The epidermis to swell and block the apocrine sweat ducts.
Scattered myoepithelial cells lie between?
The secretory cells of Secretory Coil and the basement membrane
What is the benefit of the eccrine sweat glands keeping the skin moist and pliable?
The skin can grip better.
Anti‑perspirants are rarely able to block...
Their own ducts
What is the main characteristic of eccrine sweat glands?
They are thermoregulatory
Cystic fibrosis patients are particularly vulnerable to salt loss in sweat because the coiled ducts of their eccrine sweat glands are incapable of ______ .
Transporting chloride
What are Apocrine glands?
Tubular glands that extend deep into the Hypodermis
An acclimatized athlete should only need...
Water
The apical cells of the coiled duct are ______ but not ion‑proof
Waterproof
When are all of the secretory granules of the apocrine gland discharged at once?
When the gland is stimulated to secrete
Eccrine sweat glands have a higher secretion pressure than _________ .
apocrine glands
Laymen often refer to...
apocrine sweat glands
What controls Secretion?
autonomic nervous system
What is the function of the straight duct of eccrine sweat gland?
carries the sweat to the body surface
The secretory coil has two types of secretory cells. Which ones are they?
clear cells and dark cells
What does the apocrine gland lacks?
coiled duct
The secretory coil s found at the level of the _______.
deep boundary of the reticular dermis.
What is the function of the coiled duct of eccrine sweat gland?
desalinates the gland. Absorbs the salt in the sweat.
At puberty, the female breast responds to _______ secreted by the ovaries
estrogen and progesterone
What is the function of the secretory coil of eccrine sweat gland?
produces sweat
Fusiform myoepithelial cells develop from the _______ and surround the duct in a helical pattern
proliferating duct cells
What does the areolar contain?
sebaceous glands, apocrine glands, abundance of melanocytes
