Venom of the Chilean Latrodectus mactans Alters Bovine Spermatozoa Calcium and Function by Blocking the TEA-sensitive K+ Current
Por:
Navarrete P., Martínez-Torres A., Gutiérrez R.S., Mejía F.R., Parodi J.
Publicada:
1 ago 2010
Resumen:
The morphology and size of spermatozoa make it difficult to study the functional properties of the plasma membrane, however, some studies have revealed the presence of a number of ion channels in this cell. We measured the calcium (Ca++) influx induced by depolarization of the plasma membrane and by venom isolated from the Chilean black widow spider (Latrodectus mactans), and functional changes in the presence of either high potassium or total venom. Our results indicate that the venom increased the Ca++ influx, with an EC50 of 6.1 mu g/mL and triggering the acrosome reaction in 43.26% of the cells. The application of potassium (10mM K+) or total venom (10 mu g/ mL) did not affect the morphology or DNA stability of the sperm. The effects induced by high K+ and venom suggest that direct blocking of K+ currents alters the passive properties of the plasma membrane, leading to the entry of Ca++. These results show the importance of functional changes induced by depolarizing the spermatozoa
Filiaciones:
Navarrete P.:
Departamento de Ciencias Preclnicas, Facultad de Medicina, Universidad de la Frontera, Chile
Martínez-Torres A.:
Univ Nacl Autonoma Mexico, Inst Neurobiol, Dept Neurobiol Mol & Celular, Lab Neurobiol Mol & Celular 2, Mexico City, DF, Mexico
Gutiérrez R.S.:
Centro de Neurociencia y Biología de Péptidos, BIOREN, Universidad de la Frontera, Chile
Mejía F.R.:
Centro de Neurociencia y Biología de Péptidos, BIOREN, Universidad de la Frontera, Chile
Parodi J.:
Centro de Neurociencia y Biología de Péptidos, BIOREN, Universidad de la Frontera, Chile
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