The effects of external K+ and Na+ on the chemotaxis of rabbit peritoneal neutrophils.
Extracellular K+ enhances the chemotactic responsiveness  and spontaneous movememt of rabbit peritoneal neutrophils but is not required for these functions. Other monovalent cations act the same; the rank order of their effectiveness is K+ = NH4 greater than Rb+ Cs+ greater than Li = Na. The K+ specific ionophore, valinomycin (10-7 M) inhances chemotaxis in the presence of K+ but not in its absence; another K+ specific ionophore, nigericin (10-7 M) inhibits chemotaxis in the absence of K+ but not in its presence. Ouabain (5 x 10-6 M) prevents the enhancing effects of K+ on chemotaxis. Removing the Na+ of the buffer and substituting it with K+, choline or glucose greatly enhances spontaneous motility but depresses chemotactic activity. One hypothesis suggested by the above results is that as a part of their action, chemotactic factors stimulate a net influx of K+ into the neutrophil; an alternative or additional hypothesis is that chemotactic factors stimulate a net efflux of Na+ from the neutrophil.
D000818:Animals; D001692:Biological Transport; D002414:Cations, Monovalent; D002633:Chemotaxis / Q000187:drug effects; D002794:Choline / Q000502:physiology; D005947:Glucose / Q000502:physiology; D009504:Neutrophils / Q000502:physiology*; D009550:Nigericin / Q000494:pharmacology; D009994:Osmolar Concentration; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000502:physiology*; D011817:Rabbits; D012964:Sodium / Q000502:physiology*; D014634:Valinomycin / Q000494:pharmacology
D002414:Cations, Monovalent; D014634:Valinomycin; D010042:Ouabain; D012964:Sodium; D005947:Glucose; D002794:Choline; D009550:Nigericin; D011188:Potassium