Norepinephrine-induced migration of SW 480 colon carcinoma cells is inhibited by beta-blockers

beta -Adrenoceptors are highly expressed on SW 480 colon carcinoma cells as was assessed by flow cytometry, We investigated the influence of norepinep hrine on the migration of these cells using time-lapse videomicroscopy. Nor epinephrine-treatment increased the locomotor activity within the populatio n from 25% spontaneously locomoting cells to 65% locomoting cells. The beta 1/2-blocker propranolol but not the beta1-blocker atenolol inhibited this i ncrease, The intracellular signaling solely of norepinephrine-induced locom otion involved protein tyrosine kinase activity, whereas both spontaneous a nd norepinephrine-induced migration were reduced by inhibiting phospholipas e C gamma and protein kinase C alpha activity. In summary, norepinephrine-i nduced locomotion of SW 480 cells is beta2-adrenoceptor mediated and distin ct from spontaneous locomotion concerning the PTK involvement.