Contractile Vacuoles

The Physiology of Contractile Vacuoles

Hydroid Stolonal Contractions Mediated by Contractile Vacuoles

The growth and development of colonial hydroids is dependent upon a flow of gastrovascular fluid through a common vasculature. Gastrovascular flow is believed to be driven by polyp contractions, stolonal contractions and endodermal ciliation. In the athecate hydroid Hydr•actinia symbiolongicarpus we found that polyp contractions, stolonal contractions and gastrovascular flow were only weakly co...

Contraction of Isolated Contractile Vacuoles from Amoeba Proteus

The contractile vacuole of freshwater protozoa is involved in regulation of cell volume and of intracellular solutes (6, 13, 22) . Despite the longstanding interest in this organelle and knowledge of its functional significance, little is known of the mechanisms of the primary actions of the contractile vacuole, namely, the formation and expulsion of the vacuolar fluid . This report is concerne...

Proton pumps populate the contractile vacuoles of Dictyostelium amoebae

Amoebae of the eukaryotic microorganism Dictyostelium discoideum were found to contain an interconnected array of tubules and cisternae whose membranes were studded with 15-nm-diameter "pegs." Comparison of the ultrastructure and freeze-fracture behavior of these pegs with similar structures found in other cells and tissues indicated that they were the head domains of vacuolar-type proton pumps...

The Physiology of Contractile Vacuoles X. Effects of High Hydrostatic Pressure on the Contractile Vacuole of a Suctorian

INTRODUCTION The effects of high pressure on living material are little understood and probably complicated. In a number of cases the tendency of cytoplasmic inclusions to become stratified by centrifuging is increased, and this is attributed to a decrease in protoplasmic viscosity (Marsland, 1942). High pressure is therefore considered to solate protoplasmic gels. In addition, high pressure af...