Lys-bradykinin stimulates Na+ influx and DNA synthesis in cultured human fibroblasts.
The effect of Lys-bradykinin on net Na+ influx in serum-deprived cultured human fibroblasts (HSWP cells) was measured. It was found that Lys-bradykinin stimulates net Na+ influx with a K1/2 of 1 nM. When Lys-bradykinin was combined with epidermal growth factor, vasopressin and insulin, the net Na+ influx stimulated was comparable with that measured in response to 10% serum. The above combination of growth factors also was found to stimulate DNA synthesis to 92% of the serum-stimulated levels in HSWP cells and to support cell growth over a period of 6 days. In addition, it was observed that the Na+ influx stimulated by Lys-bradykinin or by the combination of four growth factors was completely inhibited by the amiloride analog benzamil. Thus Lys-bradykinin presumably stimulates the same Na+ transport system as is stimulated by serum. Finally, the present results suggest that an increase in Na+ influx always accompanies DNA synthesis in HSWP cells. On the basis of these observations, it can be hypothesized that Na+ influx is a necessary event to stimulate DNA synthesis.
D000584:Amiloride / Q000031:analogs & derivatives / Q000494:pharmacology; D002460:Cell Line; D004261:DNA Replication / Q000187:drug effects*; D004815:Epidermal Growth Factor / Q000494:pharmacology; D005347:Fibroblasts / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000494:pharmacology; D007609:Kallidin / Q000494:pharmacology*; D012964:Sodium / Q000378:metabolism*; D014667:Vasopressins / Q000494:pharmacology
D007328:Insulin; C013407:benzamil; D014667:Vasopressins; D007609:Kallidin; D004815:Epidermal Growth Factor; D000584:Amiloride; D012964:Sodium