FROZEN‐THAWED BOAR SPERM: ISOLATION OF MEMBRANES and FLUIDITY MEASUREMENT

Buhr, M.M.; Pettitt, M.J.

doi:10.1111/j.1439-0531.1995.tb00018.x

Cited by 12 publications

(10 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Membranes isolated from the heads of fresh and cryopreserved boar sperm have domains with different molecular dynamics, indicated by both different initial states of fluidities and different patterns of change in fluidity with time, confirming and expanding previous results (Pettitt and Buhr, 1998;Harrison and Miller, 2000). Different domains have been recognized in electron micrographs of fixed boar sperm membranes (Peterson et al, 1987) and probes used in the present study have allowed detection of different domains in membranes from bovine (Buhr et al, 1993) and porcine sperm (Buhr and Pettitt, 1996). The current study demonstrates that the concentration of glycerol used to freeze whole sperm alters the dynamics of specific domains in the head plasma membranes of the thawed sperm.…”

Section: Discussionsupporting

confidence: 89%

“…Ultrastructural differences within the plasma membrane overlying the anterior of the head have been found (Peterson et al, 1987;Harrison et al, 1996), and chilling induces a site-specific rearrangement of membrane ultrastructure, suggesting that there are domains with different temperature sensitivities in sperm membranes (de Leeuw et al, 1990;Buhr et al, 1994) as in platelets (Crowe et al, 1999). Domains exist in boar sperm membranes (Buhr and Pettitt, 1996; Ladha et al, 1997) and the various major components of the cryopreservation extender act and interact to alter molecular relationships within these domains, which are measurable as a change in fluidity of the domain (Pettitt and Buhr, 1998). Knowing that the presence or absence of glycerol in a cryopreservation medium affected membrane domains in boar sperm (Pettitt and Buhr, 1998), the present study hypothesized that glycerol would alter domain fluidity in conjunction with altered function of intact sperm.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Cryopreservation in Different Concentrations of Glycerol Alters Boar Sperm and Their Membranes

Buhr

Fiser²,

Bailey

et al. 2001

Journal of Andrology

View full text Add to dashboard Cite

To test the hypothesis that glycerol would concomitantly affect sperm membrane structure and the function of the intact cells, boar semen (4 ejaculates from 4 boars) was cryopreserved in an egg yolk extender with 0%, 2%, 4%, or 8% glycerol in 0.5-mL straws using previously derived optimal cooling and thawing rates. Increasing glycerol concentrations increased spermatozoal progressive motility immediately after thawing and after 2 hours at 43 degrees C, but decreased the percentage of sperm with normal acrosomal morphology. The mathematical products of the motility and acrosomal integrity scores (MOT x NAR index) were low in 0% and 8% glycerol, and significantly higher in 2% and 4% glycerol. The fluidity of sperm-head plasma membranes, a measure of molecular interaction, was assessed with the lipid probes trans-parinaric acid and cisparinaric acid (tPNA, cPNA), during a 2.5-hour incubation with or without 1 mM Ca2+. Membrane fluidity detected by each probe differed significantly, indicating the presence of at least 2 domains whose constituent molecules had unique dynamics. Behavior of each domain was radically altered by cryopreservation. Increasing glycerol concentration caused a variably faster loss of fluidity in the cPNA domain, and had highly variable effects on fluidity change over time in the tPNA domain. Normal acrosomal ridge (NAR) and the MOT x NAR index correlated significantly with the fluidity of the more mobile cPNA domain (+/- 1 mM Ca2+), supporting the hypothesis of an interrelationship of glycerol concentration during cryopreservation with sperm membrane structure and cell function. The MOT x NAR index may be a useful guide in choosing optimal cryoprotectant concentrations.

show abstract

Section: Discussionsupporting

confidence: 89%

mentioning

confidence: 99%

Cryopreservation in Different Concentrations of Glycerol Alters Boar Sperm and Their Membranes

Buhr

Fiser²,

Bailey

et al. 2001

Journal of Andrology

View full text Add to dashboard Cite

show abstract

“…Cryopreservation (dilution, cooling, freezing, and thawing) of boar sperm causes structural and functional damage in sperm head membranes, altering both the chemical composition and the dynamic behavior of the membrane lipids. Membranes from fresh boar sperm have multiple membrane domains [38,48,49] whose basic fluidity is altered by cryopreservation of the intact sperm [47,50]. Even the lipids alone, whether isolated from the HPM of fresh or frozen-thawed boar sperm, form domains with unique fluidities, but the HPM lipids from cryopreserved sperm have a different composition and dynamic behavior [15,51].…”

Section: Discussionmentioning

confidence: 99%

Incorporating Lipids into Boar Sperm Decreases Chilling Sensitivity but Not Capacitation Potential1

Bailey

Buhr

2001

Biology of Reproduction

Self Cite

View full text Add to dashboard Cite

Fresh boar sperm were incubated with small unilamellar liposomes composed of either the total lipids extracted from head plasma membranes (HPM) of fresh boar sperm or selected lipids (SL) of five defined phospholipids with specific acyl chains. To optimize fusion, liposomes with 2 mol% octadecyl rhodamine fluorophore in Beltsville Thawing Solution +/- 1 mM CaCl(2) were incubated at 35 degrees C with 1;ts 10(7) or 10(8) spermatozoa/ml and monitored over 60 min, using flow cytometry and fluorescence microscopy. The HPM fused to both sperm concentrations faster than SL but was equivalent by 30 min (10(8) sperm/ml) or 60 min (10(7) sperm/ml; 57.5 +/- 3% and 67.1 +/- 8% sperm fused to HPM and SL, respectively) +/- Ca(2+). Neither HPM nor SL affected onset of capacitation or spontaneous or ionophore-induced acrosome reactions at 0 or 3 h (chlortetracycline and fluorescein isothiocyanate-Pisum sativum agglutinin; n = 3). During cooling and after cryopreservation (n = 4 ejaculates), SL but not HPM significantly improved sperm motility and viability (Sybr14/propidium iodide staining) +/- 20% egg yolk, but egg yolk alone was more effective than SL alone. Liposomes of complex composition can fuse to boar sperm without harming in vitro capacitation or acrosome reaction and reduce sperm chilling sensitivity.

show abstract

“…Moreover, the sperm membranes appear to be the primary site of damage induced by reduced temperature and alterations in their molecular composition can impair the fertilization processes [3]. Evidence is assembled to suggest that lyophilized lipoprotein fraction of ostrich egg yolk (LPFo) has an overwhelming beneficial effect on the structural and functional integrity of boar plasma membrane during liquid storage [4][5][6] and cryopreservation of semen [7].…”

Section: Introductionmentioning

confidence: 99%

Interactions of egg yolk lipoprotein fraction with boar spermatozoa assessed with a fluorescent membrane probe.

Fraser

Zasiadczyk²,

Strzeżek³

2010

Folia Histochem Cytobiol.

View full text Add to dashboard Cite

Abstract:The interactions of a fluorescent membrane probe, 1-anilinonaphthalene-8-sulfonic acid (1,, with boar spermatozoa were followed through the use of lipoprotein fraction of ostrich egg yolk (LPFo). Semen samples, extended in Kortowo 3 (K3) extender, were supplemented with 2% or 5% LPFo and stored for 3h at 16°C. Additionally, cold shocktreated spermatozoa (1h at 4°C) were stored in K3 extender supplemented with LPFo for 3h at 16°C. In each boar, the fluorescent enhancement of ANS was observed in K3-extended semen supplemented with LPFo, prior to storage. Following storage, there was a significant increase in LPFo-ANS fluorescence, particularly in the sperm membrane overlying the head and midpiece regions. There were significant differences among the boars with respect to the sperm populations defined by the LPFo-ANS fluorescence. Sperm viability was not significantly affected during the storage period. Furthermore, the proportions of spermatozoa defined by the different patterns of LPFo-ANS fluorescence were low and remained unchanged after storage of cold shock-treated spermatozoa with 2% or 5% LPFo, suggesting irreversible damage to the sperm membrane architecture. These findings indicate that the ANS fluorescent probe could be used to shed more light on the nature of the interactions between LPFo and sperm membrane following semen preservation. Such valuable information could contribute to the development of an optimal protocol for cryopreservation of boar semen.

show abstract

FROZEN‐THAWED BOAR SPERM: ISOLATION OF MEMBRANES and FLUIDITY MEASUREMENT

Cited by 12 publications

References 19 publications

Cryopreservation in Different Concentrations of Glycerol Alters Boar Sperm and Their Membranes

Cryopreservation in Different Concentrations of Glycerol Alters Boar Sperm and Their Membranes

Incorporating Lipids into Boar Sperm Decreases Chilling Sensitivity but Not Capacitation Potential1

Interactions of egg yolk lipoprotein fraction with boar spermatozoa assessed with a fluorescent membrane probe.

Contact Info

Product

Resources

About