What the Heck is this bullshit. Flashcards
superficial fascia
subQ tissue
fascia types
superficial and deep
deep fascia
dense and organized
no fat
varied thickness
retinaculum
deep fascia associated with tendons
subserous
deep fascia lining the body cavities
bursae
closed sacs of serous membranes allow lubriction
fibroblasts
responsive to mechanotransduction
allow us to produce ECM
macrophages
break down the ECM
mast cell
vasoactive ( can recruit cells)
plasma cell
produce antibodies
cells of fascia?
fibroblast, macrophage, mast cell, plasma cell
what makes up ECM
glycoproteins, proteoglycans, cells, and collagen
ECM is tunable to mechanical needs
-allows for transduction of signals to cell
types of connective tissue
have differences based on the ECM components and cells present
have loose (areolar), dense regular, and dense irregular connective tissue
fibroblast
member of the connective tissue type of cells
-related to cartilage, bone, adipose, and smooth cells
fibroblasts can interconvert within this family - rare**
fibroblast can penetrate and become entangled within the ECM
-responsible for remodeling the matrices
normal functions of fibroblasts?
connective tissue component
wound healing - produce new collage to repair damage
mesenchymal cells - immature fibroblasts
stromal cells - bone marrow immature fibroblasts
cell-matrix tension state
dependent on ECM environment
-collagen density, matrix restraint, and growth factors
low tension - non-pathological
high tension - pathological
-fibroblasts activated in high tension
four different dimensions
migratory vs contractility
low tension vs high tension
local remodeling
involves one fibroblast
global matrix contraction
what we focus on with OMT**
multiple fibroblasts
tensegrity
tensional integrity
unison of tensioned and compressed parts of structure
affects microtubule formation in fibroblasts
low tension state
fibroblast forms dendritic extensions with microtubules to resist contractile tension
internal clutch
high tension state
contractile tension is transferred to the ECM
-no need for microtubules
external clutch
fibroblast migration
requires dendritic extensions
therefore more likely in low tension state
myofibroblast
fully differentiated fibroblast
adapt contractile activity to the level of stress in the surrounding
highly contractile
- stress fiber formation - increase expression of alpha-smooth muscle actin
TGF-beta release
requires high tension and contractile state
maybe results in organ fibrosis?
ex/ dupuytrens contracture
-fixed contraction of hand
mechanotransduction
ability of cell to respond to mechanical changes
PDGF
pro-contractile in low tension
anti-contractile in high tension
LPA
phospholipid signals
induces proliferation of fibroblasts
S1P
growth factor and cytokine
induces proliferation and inflammation
pro-contractile in high tension state
focal adhesions
link the ECM to actin cytoskeleton
composed of alpha-beta heterodimers, integrins
integrin activity
begin to cluster when activated
focal adhesion complexes become larger and larger
-become supermature focal adhesion
fibronectin
under high stress, can unfold to reveal sites which autocatalyze fibril formation
methods of mechanical cell stiumulation
compression and static stimuli
shear force
fluid force
relevant for cells lining fluid filled cavities and vessels
however, all cells are bathed in fluid
very difficult to calculate the shear force on cells
types of stretch in cell
uniaxial (only one direction) -align along perpendicular axis biaxial (multiple directions) -align due to different axis of stretch equibiaxially (equal in all directions) -cells do not align due to major axis of strain
myosin V
can induce contraction
not muscle, just a normal cell ability
