Fibrin(ogen) degradation product peptide 6A increases femoral artery blood flow in dogs.
To determine the effects of peptide 6A (a fibrinogen-degradation product) on femoral blood flow, anaesthetized dogs were given saline or peptide 6A intravenously in random order. Bolus injection of peptide 6A (10, 20 or 50 mumoles) caused a short-lasting dose-dependent decrease in femoral bed resistance and an increase in femoral blood flow. Continuous infusion of peptide 6A (50 mumoles min-1) resulted in a sustained decrease in resistance and an increase in femoral artery blood flow (54 +/- 33%), with a small, insignificant decrease in femoral artery mean pressure. Indomethacin pretreatment caused only slight attenuation of the peptide 6A-induced increase in femoral blood flow. In in vitro experiments, peptide 6A relaxed rings of femoral artery, and this effect was associated with an increase in 6-keto-PGF1 alpha in the vascular ring supernatants and in the tissue cyclic GMP concentrations. Peptide 6A-induced relaxation was abolished by de-endothelialization, but not by treatment with indomethacin. These observations suggest that peptide 6A induces vasorelaxation largely by stimulating release of endothelium-derived relaxing factor. PGI2 release appears to play only a minor role in the vasodilator effects of peptide 6A in the femoral bed.
Saldeen
K
K
Department of Medicine, University of Florida, Gainesville.
Nichols
W
W
Lawson
D
D
Andersson
R
R
Saldeen
T
T
Mehta
J
J
D015121:6-Ketoprostaglandin F1 alpha / Q000096:biosynthesis; D000818:Animals; D006152:Cyclic GMP / Q000096:biosynthesis; D004285:Dogs; D011464:Epoprostenol / Q000096:biosynthesis; D005263:Femoral Artery / Q000187:drug effects* / Q000378:metabolism; D005338:Fibrin Fibrinogen Degradation Products / Q000494:pharmacology*; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000378:metabolism; D009569:Nitric Oxide / Q000096:biosynthesis; D012039:Regional Blood Flow / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects
D005338:Fibrin Fibrinogen Degradation Products; C026893:fibrinogen peptide 6A; D009569:Nitric Oxide; D015121:6-Ketoprostaglandin F1 alpha; D011464:Epoprostenol; D006152:Cyclic GMP; D007213:Indomethacin