CT Flashcards
examples of sulfated GAGs
keratin sulfate, chondroitin sulfate, heparin sulfate, dermatin sulfate
example of non-sulfated GAGs
HA
fibroblasts derived from:
mesenchyme
division of fibroblast occurs when
primarily during wound healing
types of cells fibroblast can change into
adipocytes, chondrocytes and osteoplasts
when do fribroblasts change into chondrocytes
during fibrocartilage formation
when do fibroblasts change into osteoblasts
certain pathologies
functions of fibroblasts
structural and defense
what is the structural function of fibroblasts
product matrix components; healing: produce growth factor & cytokines, scar formation
what is the defense function of fibroblasts
produce cytokines & enzymes (collagenase, elastase); phagocytosis
fibrocyte
mature less active fibroblast that is flat in appearence; live longer w/lower energy and oxygen requirements; produce GAGs, other molecules and reticular fibers
what can fibrocytes not do
produce new collagen I or elastin fibers
function of fibroblasts
maintain tissue
myofibroblast
posses features of fibroblast and smooth muscle cells
function of myofibroblast
wound closure and tooth eruption
adipocytes
do not divide or chnage into other cell types; derived from mesechye cells
function of adipocytes
lipid storage: energy source, thermoregulation and cushening of organs
plasma cell
do not divide and have short lives; found in CT and lymphatic tissues/organs; derived from B lympocytes
funtion of plasma cells
to produce antibodies
macrophages
aka histiocytes; contain residual bodies in cytoplasm; can divite; derived from monocytes; part of mononuclear phagocyte system
MPS
Mononuclear Phagocyte Sytem: all members arise from a common ancestor in bone marrow and are able to phagocytize and display particular receptors
examples of MPS
kupffer cells, alveolar macrophages, monocytes, microglia, langerhans cells, osteoclasts
function of macrophages
phagocytosis, act as APC, creat foreign body giant cells, release cytokins and other products
what do macrophages phagocytos
debris and microorganisms
APC
Antigen Presenting Cell; present infor about a foreing antigen to T-helper cells
foreign body giant cells
created by the fusion of many macrophages in response to a sizable foreign object or some pathogens
mast cells
large cells containing cytoplasmic granules; fount in CT proper, by small blood vessels and under epithelium; occatonally divide; derived from a precursor cell from bone marrow
mast cell mediated events
basic inflammatory reaction, immediate hypersensitivity response, anaphylaxis, asthma
basic inflammatory reaction
mast cell trauma or phagocytosis in response to dead cells, debris and damaged fibers; localized reaction of mast cell degranulate; histamine first reactant followed by leukotrienes and heparin
histamine
primary mediator in basic inflammation; increased permeablilty of capillaries and venules, dilates arterioles
leukotrienes
second mediator in basic inflammation
Heparin
third mediator in basic inflammation
immediat hypersensitivity response
simple allergy; IgE and allergin complex
anaphylaxis
IgE/allergin in blood; sytemic mast cell and basophil degranulation and secretion
anaphylactic shock
circulatory shock; cardiovascular collapse caused by extensive blood loss
extrinsic asthma
allergins known; often childhood onset
intrinsic asthma
allergin unknown; may develope in aduls following an upper of lower respiratory infection
asthma stimulated by:
IgE/allergin complex and/or fatigue, stress, fumes, endrocrin changes, emotionst etc.
primary problem in asthma
leuotrienes contract smooth muscle in bronchioles
secondary difficulties caused by asthma
inflammation; excess fluid and decreased oxygen diffusion
cells in CT
fibroblast, fibrocyte, myofibroblast, adipocyte, plasma cell, macrophages, mast cells, leukocytes, mesenchyme cells, reticular cells
types of leukocytes
monocytes, neurophiles, eosinophils, basophils and lymphocytes
monocytes
become macrophages in CT
neutrophils
attracted to sites of acute inflammation; good at phagocytosis of debris and bacteria
eosinophils
combat parasitic worms; attracted to allergic inflammation
basophils
similar to mast cells; initiate/influence and maintain inflammation
lymphocytes
usually not many in CT; attracted to chronic inflammation sites
funtion of lymphocytes
humerall and cell mediated immunity
mesenchyme cells
divide by numbers decrease with age; functional to change into another cell type
reticular cells
derived from mesenchyme dcells; produce collagen III (reticular fibers)
what do fibroblast have in common with reticular cells
fibroblast produce reticular fibers when needed on a temporary basis (wound healing) while reticular cells are found when collagen III is needed on a permanent basis
where do reticular cells produce collagen III on a permenant basis
endocrin and lymphatic organs
classification of CT
connective tissue proper and specialized CT
Connective tissue proper
loose CT, dense CT
types of Dense CT
dense irregular, dense regular, reticular CT and adipose
types of loose connective tissue
loose areolar and loose irregular
characteristics of loose CT
larger number of cells, many cell types, fewer fibers, increased amounts of ground substance, quite vasular
loose areolar
greater and lesser omentum; around blood vessels and in other small areas
loose irregular
papillar layer of dermis, directly beneath epithelium in organs
characteristics of dense CT
fewer cells, fewer cell types, many fibers, less ground substance, less vascular
dense irregular
reticular layer of dermis, nerve sheaths and organ capsules
dense regular
tendons, ligaments and aponeurosis
reticular CT
primary reticular fibers and reticular cells; edocrine an dlyphatic organs
adipose
adipocyte cells, quite vascular; function in lipid storage
general CT rules
1) increased number of cell types will increase healing potential 2) increased vascularity will increase healing potential
specialized CT
cartilage, bone and blood
