Breast histology Flashcards
What kind of gland is the breast
subcutaneous
is the breast part of the body wall
no, it sits anterior to it as well as deep fascia and muscles
How many lobes make up the secretory tissue of the breast
15-25 lobes
what does each lobe consist of
a compound tubulo-acinar gland which drains via ducts leading towards the nipple
what are lactiferous ducts and where do they open up to
secretory ducts of the lobe, leading to the nipple
what are lobules
tubuloalveolar glands
what are lobes
segments of the breast
which fibrous bands separate the secretory lobes of the breast
Where are they most pronounced
suspensory ligaments of the breast (of Cooper)
upper breast
what are lactiferous sinuses
dilatation in the lactiferous duct near the nipple
what does the TDLU stand for
terminal duct lobular unit
what is the TDLU
basic functional secretory unit of the breast
aka lobule
what kind of connective tissue is found outside the lobule
dense CT
what kind of connective tissue is found inside the lobule
loose CT surrounds the acini within the lobule
what kind of tissue is found between the lobules
adipose tissue
what type of cells are lobules composed of
epithelial cells
what kind of secretory epithelial cells line the acini within lobules
cuboidal/columnar
what does MEp stand for
myoepithelial cells
what are MEp (myoepithelial cells)
contractile epithelial cells that surround secretory cells
they are half way between smooth muscle and epithelial cells
function of MEp
to push material out of ductal system by contraction
what epithelium lines larger ducts eg lactiferous ducts
stratified squamous more superficially
stratified cuboidal deeper
which epithelium covers the nipple
thin pigmented keratinised stratified squamous epithelium
is there smooth muscle present in the nipple
yes alongside dense irregular CT
what is different about sebaceous glands in the nipple in comparison to the rest of the skin
sebaceous glands in the nipple open up directly on to the surface
in the rest of the skin, they open onto hair follicles first
what happens to epithelial cells during the luteal phase
increase in height
lumen becomes enlarged
secretions appear in the duct
what happens to cells of the breast during pregnancy
1st trimester - branching of smaller ducts + proliferation of epithelium and MEp
2nd - glandular tissue develops
3rd - secretory alveoli mature
which hormones stimulate proliferation of secretory tissue in pregnancy
oestrogen
progesterone
what is the composition of human milk
water 88% protein 1.5% carbohydrate 7% lipid 3.5% ions, vitamins, IgA
which proteins are found in human milk
lactalbumin
casein
what are the 3 methods of secretion
which is the most common
Holocrine
Apocrine
Merocrine - most common
what is holocrine secretion and where is it seen
contents accumulate in the cell which then bursts open to release material and entire contents of the cell
seen at the nipple
what is apocrine secretion
globules of fat free in the cytoplasm are released with a small amount of cytoplasm and membrane surrounding it
what is merocrine secretion
material is packaged up into vacuole which merges with the apical cell membrane and opens up
nothing else is released except for the material
what happens to secretory cells of TDLU after menopause
they degenerate, leaving only ducts
how does the breast differ in males from females
males have a rudimentary duct system but no lobules as they do not need to secrete milk
