Spermatozoa "Whip it Good"
 Researchers have identified a key component of the mechanism spermatozoa use to abruptly convert their tail motion from a steady swimming undulation to the Devo-like "whip it good" snap that thrusts them into an egg.
The finding opens a new research pathway that the researchers said could help scientists both recognize new forms of male infertility and design new contraceptives to thwart sperm entry into the egg. What's more, they said, the exquisitely delicate analytical technique they used to eavesdrop on the electrical currents inside the squirming spermatozoa cell could literally open a new window into its largely mysterious inner workings.
"CatSper the Friendly Sperm"It has long been known that a spermatozoa's arrival in the alkaline environment of the female reproductive tract triggers its tail's whiplike motion, called hyperactivation. In 2001, the researchers showed that a protein called CatSper1, found only in the sperm tail, was required for male fertility. Subsequently, with colleagues at the University of Washington and at the University of Texas Southwestern, CatSper was found to be required for hyperactivation. CatSper proteins are components of pores in the sperm cell membrane called ion channels. In an alkaline environment, these pores open and allow calcium to enter the cell.
Researchers had attempted to study the CatSper ion channel with a technique called patch clamp recording. Patch clamp studies on spermatozoa with remnant cytoplasmic droplets revealed that CatSper1 was a major component of the calcium ion channel responsible for alkaline-activated hyperactivation and male fertility. Since we know that defects in CatSper1 block fertilization in mice, and since the channels in human sperm are very similar, there's no reason to believe we can't develop a femal or male birth control pill that would block the protein before it functions to hyperactivate sperm, preventing fertilization."
Paul Ellis - Men's Health 
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