Cyclic AMP in cells adhering to bioincompatible (Cuprophan) and biocompatible (AN69) substrates

The processing of signals produced when cells contact biomaterials was examined. Of the several possible pathways, this study focuses on the amount of cAMP that accumulated in NIH 3T3 cells during the first 45 min after the cells contacted the bioincompatible membrane Cuprophan (CU) and the biocompatible membrane AN69. The cells that adhered to CU contained more cAMP than those that attached to AN69. This might be because the cells did not spread but remained rounded up under scanning electron microscopy. There was no increase in cAMP in the cells that did not adhere to CU. The cAMP-modulating agents, forskolin and isoproterenol, were used to assess the cAMP-generating capacity of adenylylcyclase in cells adhering to CU and AN69. This capacity was not affected by a high concentration (100 microM) of forskolin. Isoproterenol had no effect on the cAMP content of the cells, demonstrating that beta adrenergic receptors are not implicated in the activation of cAMP production by membranes. The bioincompatibility of CU seems to be responsible for the greater amount of cAMP in adherent cells, and this parameter could provide an index for assessing biocompatibility.