Biochemical characterization and membrane,fluidity of membranous vesicles isolated from boar seminal plasma.

LIDIA L. PIEHL , HUMBERTO CISALE , NATALIA TORRES ,FRANCISCO CAPANI , NORMA STERIN-SPEZIALE , ALFREDO HAGER

ANIMAL REPRODUCTION SCIENCE

Año: 2006 p. 401 - 410

0378-4320

Mammalian seminal plasma contains membranous vesicles (MV), which differ in composition and origin. Among these particles, human prostasomes and equine prostasome-like MV have been the most studied. The aim of the present work is to characterize the biochemical composition and membrane fluidity of MV isolated from boar seminal plasma. The MV from boar seminal plasma were isolated by ultracentrifugation and further purification by gel filtration on Sephadex G-200. The MV were examined by electron microscopy (EM), amount of cholesterol, total phospholipid, protein content, and phospholipid composition were analyzed. Membrane fluidity of MV and spermatozoa were estimated from the electron spin resonance (ESR) spectra of the 5-doxilstearic acid incorporated into the vesicle membranes by the order parameter (S). The S parameter gives a measure of degree of structural order in the membrane and is defined as the ratio of the spectral anisotropy in the membranes to the maximumS). The S parameter gives a measure of degree of structural order in the membrane and is defined as the ratio of the spectral anisotropy in the membranes to the maximum