Ion channels in boar sperm plasma membranes: characterization of a cation selective channel. |
| |
Authors: | T Cox P Campbell R N Peterson |
| |
Institution: | Department of Physiology, School of Medicine, Southern Illinois University, Carbondale 62901. |
| |
Abstract: | Plasma membranes isolated from cauda epididymal and ejaculated boar sperm were inserted into planar lipid bilayers and examined for the presence of ion channels. Channel fusion was frequently observed; the most prominent was a nonselective cation channel which conducted K, Na, Cs, Ca, and Ba. Channel opening did not show a strict dependence on voltage but was partially blocked by verapamil, nitrendipine, and ruthenium red. A channel with these characteristics was observed when plasma membranes were isolated by high-pressure nitrogen cavitation (650 psi, 78% sperm head plasma membranes) or at very low nitrogen pressures (50 psi, 90% sperm head plasma membranes), suggesting that this channel may be present in the plasma membrane overlying the sperm head. |
| |
Keywords: | Calcium channels Ruthenium red Verapamil Nitrendipine |
|
|