Flashcards in Breast Histology Deck (20)
How many lobes make up the secretory tissue of the breast?
What is each 'lobe' of the breast made up of
A tubule-acinar gland which drains via a series of ducts leading to the nipple
What is adjacent to the secretory lobule in the breast
dense fibrous tissue surrounded by fat tissue
Describe the duct system
Terminal ductules --> intralobular collecting duct ---> lactiferous duct--> lactiferous sinus-->nipple
What type of epithelium lines the larger ducts
What type of epithelium lines the secretory acini
cuboidal or low columnar
what epithelium covers the nipple
highly pigmented keratinized stratified squamous epithelium
What changes occur in the breast during the menstrual cycle
During the luteal phase the epithelial cells increase in height, the lumina of the ducts becomes enlarged and small amounts of secretions appear in the ducts.
What changes occur in the first trimester of pregnancy
In the first trimester there is elongation and branching of the smaller ducts, combined with proliferation of the epithelial cells of the glands and the myoepithelial cells.
What changes occur in the second trimester of pregnancy
In the second trimester glandular tissue continues to develop with differentiation of secretory alveoli. Also, plasma cells and lymphocytes infiltrate the nearby connective tissue.
What changes occur in the third trimester of pregnancy
In the third trimester secretory alveoli continue to mature, with development of extensive rER.
What are all changes in pregnancy accompanies by
reduction in the amount of connective tissue and adipose tissue present
What are the effects os oestrogen and progesterone during pregnancy on the breast
stimulate proliferation of secretory tissue and fibro-fatty tissue becomes sparse.
What is the consituients of breast milk
1.5% protein (mainly lactalbumin and casein)
7% carbohydrate (mainly lactose)
What immunoglobulin is present in breast milk
What happens to the breast tissue in menopause
the secretory cells of the TDLU’s degenerate leaving only ducts. In the connective tissue, there are fewer fibroblasts and reduced collagen and elastic fibres.
By what mechanism are lipids secreted in the breast
Describe apocrine secretion
'budding off' of the fat droplets
By what mechanism is protein secreted in the breast to form breast milk