Microfabricated grooves recapitulate neonatal myocyte connexin43 and N-cadherin expression and localization

Our objective is to alter the surface topography on which cardiac myocytes are grown in culture so that they more closely resemble their in vivo counterparts. Microtex- tured silicone substrata were made using photolithography and microfabrication techniques and then coated with lami- nin. Primary cardiac myocytes from newborn rats were plated on microgrooved and nontextured substrata. Myo- cytes were highly oriented on 5 m grooves (69.8 2.0%) and significantly different, p 0.0001, compared with ran- domly oriented cells grown on nontextured surfaces (2.9 0.95%; n 19). Cells on shallower, 2 m, grooves were slightly less well oriented (46.9 4.3%, n 5, p 0.001). The lateral spacings of the grooves were altered to examine changes in cell-to-cell contact by confocal immunocytochem- istry and quantitative protein analysis. Connexin43 and N- cadherin were distributed around the perimeter of the myo- cytes plated on 1055 microgrooved surfaces, similar to the localization found in the neonate. Connexin43 expres- sion in cultures on 5 m deep grooved substrata was equal to the neonatal heart, whereas it differed in nontextured surfaces. We conclude that it is necessary to combine groove depth (5 m) and lateral ridge dimensions between grooves (5 m) in order to recapitulate connexin43 and N-cadherin expression levels and subcellular localization to that of the neonate. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 148 -157, 2003