Effect of melittin on ion transport across cell membranes
Abstract
Extensive work with melittin has shown that the venom has multiple effects,
probably, as a result of its interaction with negatively changed phospholipids.
It inhibits well known transport pumps such as the Na(+)-K(+)-ATPase and the
H(+)-K(+)-ATPase. Melittin increases the permeability of cell membranes to ions,
particularly Na+ and indirectly Ca2+, because of the Na(+)-Ca(2+)-exchange. This
effect results in marked morphological and functional changes, particularly in
excitable tissues such as cardiac myocytes. In some other tissues, e.g., cornea,
not only Na+ but Cl- permeability is also increased by melittin. Similar effects
to melittin on H(+)-K(+)-ATPase have been found with the synthetic amphipathic
polypeptide Trp-3.
Keywords:
probably, as a result of its interaction with negatively changed phospholipids.
It inhibits well known transport pumps such as the Na(+)-K(+)-ATPase and the
H(+)-K(+)-ATPase. Melittin increases the permeability of cell membranes to ions,
particularly Na+ and indirectly Ca2+, because of the Na(+)-Ca(2+)-exchange. This
effect results in marked morphological and functional changes, particularly in
excitable tissues such as cardiac myocytes. In some other tissues, e.g., cornea,
not only Na+ but Cl- permeability is also increased by melittin. Similar effects
to melittin on H(+)-K(+)-ATPase have been found with the synthetic amphipathic
polypeptide Trp-3.