Lipid fatty acid and protein pattern of equine prostasome-like vesicles.
The semen of several mammals contains vesicles of different composition and origin. We have recently reported on the presence of lipoprotein vesicles in stallion semen. To a certain extent, these resemble human prostasomes, but differ from them in amount and composition. These horse-semen prostasome-like vesicles may be important, not only in horse reproductive physiology, but also in view of stallion semen cryopreservation. In this paper, we have studied horse-semen prostasome-like vesicles and found that they possess less saturated fatty acid than human prostasomes. Moreover, their protein pattern (SDS-PAGE electrophoresis) shows that the 30-50-kDa fraction is less abundant in stallion vesicles. In addition, fluidity (measured as fluorescence anisotropy of diphenylhexatriene) is higher in horse prostasome-like vesicles than in human prostasomes, albeit being much lower than that of most membranes. These findings may be connected to some species-related differences in reproductive physiology: the vaginal milieu of the mare is not acidic and the deposition of semen is intrauterine in the horse but vaginal in humans.
Arienti
G
G
Istituto di Biochimica e Chimica Medica, Via del Giochetto, 06127, Perugia, Italy. arienti@unipg.it
Polci
A
A
De Cosmo
A
A
Saccardi
C
C
Carlini
E
E
Palmerini
C A
CA
D000818:Animals; D005227:Fatty Acids / Q000032:analysis*; D006736:Horses / Q000502:physiology*; D006801:Humans; D008297:Male; D008560:Membrane Fluidity; D010743:Phospholipids / Q000032:analysis; D011467:Prostate / Q000378:metabolism; D011506:Proteins / Q000032:analysis*; D012661:Semen / Q000737:chemistry*
D005227:Fatty Acids; D010743:Phospholipids; D011506:Proteins