INGESTION OF ASPIRIN PREVENTS PLATELET-INDUCED HUMAN FIBROBLAST GROWTH - IMPLICATIONS FOR PEPTIC-ULCER HEALING

Because aspirin (ASA) may affect peptic ulcer healing through actions on platelets (for example, by inhibiting release of growth factors), human foreskin fibroblast mitogenesis was used for two bioassays (24-h growth with H-3-thymidine incorporation and 5- to 6-day cell proliferation) for serum derived from collagen-aggregated platelet-rich plasma (PRP) or platelet-poor plasma (PPP) or from clotted whole blood (WBS). Blood was taken from five normal subjects before and 6 h after ingestion of ASA. After ASA ingestion serum (WBS or PRP) was less mitogenic (p < 0.01) by both bioassays, whereas PPP serum was not mitogenic either before or after ASA. In vitro, neither ASA nor salicylic acid alone at levels normally found in plasma with ASA use inhibited fibroblast growth. We conclude that ASA ingestion inhibits the mitogenic action of platelets on fibroblast culture by inhibiting the release of putative growth factors. Such an effect might explain the adverse effects of ASA on ulcer healing.