Prostaglandin F2 alpha-induced contraction in isolated dog cerebral, coronary and mesenteric arteries soaked in excess potassium.

Concentration-response curve for prostaglandin (PG) F2 alpha in helical strips of dog cerebral, coronary and mesenteric arteries were compared in control media and in those in which all the NaCl was replaced with isomolar KCl. Contractile responses to PGF2 alpha in concentrations up to 2 x 10(-6) M in cerebral arteries, to 10(-5) M in coronary arteries and to 5 x 10(-7) M in mesenteric arteries were not attenuated by excess K+. Contractions caused by PGF2 alpha, at least at these concentrations or lower, may not be associated with membrane depolarization.