investigations into the possible role of coupling ( gap junctions ) and three-dimensional contact in the expression of this phenomenon revealed 1 ) a correlation between cell coupling and the activity of adenylate cyclase in monolayers , 2 ) a sharp drop of cyclase activity in spheroids of coupled cells compared to monolayers , and 3 ) a decrease of coupling with age ( `` '' maturation '' '' ) of the spheroids .
C0206117
gap junctions
C0007634
cell