no edit summary
Line 23: Line 23:  
***Mesenchymal cells  
 
***Mesenchymal cells  
 
***Arise from bone marrow stroma
 
***Arise from bone marrow stroma
 +
***Histologically:
 +
****Plump and cuboidal when active
 +
****Basophilic cytoplasm
 +
****When inactive - less cytoplasm -> flattened
 
***Produce bone matrix = '''osteoid''' - uncalcified
 
***Produce bone matrix = '''osteoid''' - uncalcified
 
****Homogeneous substance
 
****Homogeneous substance
 
****Stains light pink with H&E  
 
****Stains light pink with H&E  
 
***Cell membranes are rich in alkaline phosphatase (ALP)
 
***Cell membranes are rich in alkaline phosphatase (ALP)
 +
****Possibly involved in pumping calcium across membranes
 
***Promoted by growth factors
 
***Promoted by growth factors
***Plump, cuboidal basophilic cells
+
***Have receptors for PTH
 
**'''Osteocytes'''
 
**'''Osteocytes'''
 
***Osteoblasts that have become surrounded by mineralised bone matrix
 
***Osteoblasts that have become surrounded by mineralised bone matrix
Author, Donkey, Bureaucrats, Administrators
53,803

edits