Contraction and Volume Changes of Glycerol Treated Rabbit Polymorphonuclear Leukocytes Induced by ATP and Ca 2+ 1

Abstract

Summary

Rabbit peritoneal polymorpho-nuclear leucocytes treated with a hypotonic and low ionic strength solution containing glycerol, Ca²⁺ and KCl are contracted by ATP as observed microscopically. Under the same conditions, ATP induces a decrease in cell volume as measured by a Coulter Counter. The measurement of cell volume response gives parallel results to the contractile events observed microscopically in the following respects: (1) The effect of ATP requires Ca²⁺; (2) AMP and EGTA both fail to elicit a cell response; (3) Chelation of Ca²⁺ causes a reversal of the contractile and volume responses elicited by ATP and Ca²⁺. From these parallel observations it is suggested that the microscopically observed contraction of glycerinated polymorphonuclear leukocytes induced by ATP and Ca²⁺ is a reflection of a generalised decrease in cell volume.