Stimuli for cell proliferation
a) There are existence of local wound hormone which is specific and produced by cell injury . it stimulates the mitotic division of cell .
b)
It may be that the trigger for
cell proliferation consist off some local loss of inhibitor which influences at
the cell level which permits affected cells to proliferate . his is mostly
accepted now-a-days . About inhibitory control of the cell proliferation there
are diversity of opinions..
i)
some observers refer to the
intra-cellular control as substance chalone which is a tissue specific inhibitor
and present in every tissue . during injury chalone diffuses out of the cell
permitting regeneration .
ii)
Contact inhibitor – in which
the cells are inhibited from mitotic divison by the inter chance of signals or
substance at their point of contact .
iii)
It is a kind of negative feed
back control at the genetic level of the cell .
