Effect of wall tension on DNA and protein synthesis in bovine mesenteric arteries in vitro.
The aim of this investigation was to study the effect of wall tension and calcium antagonists on DNA and protein synthesis in bovine mesenteric arteries in vitro. The wall tension of the bovine mesenteric arteries was raised by stretching the vessel wall perpendicular to the length axis of the vessel. DNA and protein synthesis were determined by measuring incorporation of 3H-thymidine into DNA and incorporation of 14C-leucine into protein respectively. Elevating the wall tension from 0.05 N to 0.5 N significantly increased 3H-thymidine incorporation and 14C-leucine incorporation after an incubation period of 3 hr. Stretch had no effect on the distribution of 3H-thymidine. The distribution of 14C-leucine was increased by stretch in regular medium and to a less extent in calcium-free medium, which suggest that stretch stimulates the membrane transport of 14C-leucine. When the tension was increased from 0.05 N to 0.5 N for 10 min. before the incubation with 3H-thymidine, no effect was found. One microM nifedipine or felodipine inhibited the increase in 3H-thymidine incorporation caused by stretching, while no effect was found on 14C-leucine incorporation. In calcium-free medium, stretch-induced DNA synthesis was completely abolished. 14C-Leucine incorporation was impaired in calcium-free medium but the stretch-induced increase still remained. The results suggest that mechanical force may play an important role in DNA synthesis and protein metabolism of vascular smooth muscle.
Department of Pharmacology, Linköping University, Sweden.
Y
Y
Chen
L G
LG
Mårtensson
K L
KL
Axelsson
L
L
Lundholm
H J
HJ
Arnqvist
D000818:Animals; D001692:Biological Transport; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002417:Cattle; D004247:DNA / Q000096:biosynthesis*; D004261:DNA Replication / Q000187:drug effects / Q000502:physiology; D007930:Leucine / Q000378:metabolism; D008638:Mesenteric Arteries / Q000502:physiology; D009131:Muscle, Smooth, Vascular / Q000378:metabolism / Q000502:physiology*; D014176:Protein Biosynthesis; D014664:Vasodilation
D002121:Calcium Channel Blockers; D004247:DNA; D007930:Leucine