Control of Epididymal Sperm Motility; An Approach to Male Fertility Regulation

Abstract

Thermal immobilization was designed as a simple approach to study factors controlling sperm motility. Heating dissected epididymis or isolated epididymal sperm at 48°C to 52°C for 5 min abruptly and completely immobilized the sperm. The thermally immobilized sperm showed some alteration of membrane lipids, as indicated by the response of the surface ATPase to temperature change. However, no qualitative change in the surface negative charge was detectable by the binding of the cells to DEAE‐Sephadex beads. The immobilized cells can metabolize ATP into ADP and AMP similar to the control epididymal sperm. The ATP‐dependent sliding or disintegration of sperm flagella was completely prevented in the immobolized cells. The findings suggested that heat‐treatment disrupted the integrity of the sperm membrane and the motile apparatus, resulting in the loss of sperm motility. The development of post‐testicular antifertility agents should aim at interfering specifically with these components of the sperm.

Binding of Spermatozoa to Positively Charged Beads as an Inexpensive Method to Isolate Sperm Heads and Tails

“…plaque-forming assay (Kennedy & Axelrod 1971) and isolation of plasma membrane (Jacobson et al 1974;Jacobson 1977;Jacobson & Branton 1977;Jacobson et al 1978;Kalish et al 1978). Since sperm tails are highly negatively charged (Nevo et al 1961;Bedford 1963;Yanagimachi et al 1972), we have demonstrated the strong binding between rat epididymal spermatozoa and positive beads, diethylaminoethyl (DEAE)-Sephadex (Chulavatnatol et al 1978). This paper describes further study on the binding and our attempt to apply the spermatozoa-bead interaction as a simple and inexpensive mean to isolate heads and tails of rat epididymal spermatozoa.…”

Density and distribution of anionic sites on boar ejaculated and epididymal spermatozoa

“…Methods used included whole cell microelectrophoresis (Bedford 1963;Lopez et al 1987;Nevo et al 1961), isoelectric focusing (Moore 1979), labelling with tritiated polycationised ferritin followed by scintillation counts (Toowicharanont and Chulavatnatol 1983), binding of charged beads (Chulavatnatol et al 1978) and visualisation of anionic sites in transmission electron microscopy (TEM) after direct labelling with cationic probes such as colloidal iron hydroxide, ruthenium red and cationised ferritin (Danon et al 1972;Delgado et al 1990;Fléchon 1975;Lopez et al 1987;Yanagimachi et al 1972). As concluded from electrophoretic mobility and qualitative judgment of sperm labelling density in TEM, spermatozoa were thought to successively acquire acidic groups as they migrate through the epididymis (Bedford 1963;Lopez et al 1987;Toowicharanont and Chulavatnatol 1983).…”