Fundamental Cryobiology of Mammalian Spermatozoa

Gao, Dayong; Mazur, Péter; Critser, John K.

doi:10.1016/b978-012399770-8/50007-1

Cited by 105 publications

(93 citation statements)

References 207 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…However, from the doses production point of view, effort to shorten equilibration or to eliminate it completely and thereby to accelerate sperm processing and cryopreservation is definitely desirable. On the other hand, efficiency of doses production contradicts the fact that equilibration is essential for the spermatozoa characteristics after subsequent thawing (Gao et al 1997).…”

Section: Introductionmentioning

confidence: 97%

Equilibration and freezing interactions affecting bull sperm characteristics after thawing

Doležalová¹,

Stádník²,

Biniová³

et al. 2016

CZECH J ANIM SCI

View full text Add to dashboard Cite

ABSTRACT:The objective was to determine effects of equilibration length and freezing curve type as well as their interactions on motility and live spermatozoa proportion in bull sperm after thawing. The ejaculates of 6 sires were repeatedly collected. Fresh semen was diluted with one extender and divided into 3 groups equilibrated for 30, 120, and 240 min. Subsequently, half straws of each group were frozen using standard 3-phase or 2-phase freezing curve differing in the rate of temperature decrease. Th e spermatozoa motility (M) was evaluated immediately after thawing and at 30, 60, 90, and 120 min of thermodynamic test (TDT). Live spermatozoa proportion was evaluated after thawing and at the end of TDT. Average of spermatozoa motility (AM), decrease of spermatozoa motility (MD), average proportion of live spermatozoa (ALS), and decrease of live spermatozoa proportion (DLS) through the TDT were calculated. Significant inter-sire differences in AM (0.45-17.0%; P < 0.05-0.01), MD (0.76-12.57%; P < 0.05-0.01), and ALS (0.99-23.8%; P < 0.01) were detected. The longest equilibration ensured the highest M during TDT and AM (+2.72 and +4.58%; P < 0.05-0.01), however higher MD (+4.06%; P < 0.01) compared to standard length as well. Straws freezed using 2-phase curve achieved higher M through TDT, AM (+7.3%; P < 0.01) as well as ALS (+11.77%; P < 0.01). The 2-phase curve presented higher M compared to the 3-phase freezing curve within all equilibration lengths. Significant differences in AM, MD,; P < 0.05-0.01) between equilibration length vs freezing curve interactions were determined. Results document the importance of equilibration length, freezing curve, and their interaction effect on live spermatozoa proportion and sperm motility after thawing as well as necessity of individual conditions for bulls semen processing and insemination doses production.

show abstract

Section: Introductionmentioning

confidence: 97%

Equilibration and freezing interactions affecting bull sperm characteristics after thawing

Doležalová¹,

Stádník²,

Biniová³

et al. 2016

CZECH J ANIM SCI

View full text Add to dashboard Cite

show abstract

“…The most widely used CPA, glycerol (GLY), is slightly less permeant than water, so that cells initially shrink in the hypertonic medium and then swell as GLYand water enter the cell; this occurs in both human and murine spermatozoa (Gao et al 1995, Agca et al 2002. During the freezing process, increased extracellular osmolality tends to dehydrate the cell; this is reversed upon thawing and further exacerbated when the extracellular CPA is removed and water enters the CPA-laden cell (Gao et al 1997).…”

Section: Volume Regulation By Spermatozoamentioning

confidence: 99%

The tonicity of murine epididymal spermatozoa and their permeability towards common cryoprotectants and epididymal osmolytes

Cooper¹,

Barfield²,

Yeung³

2008

Reproduction

View full text Add to dashboard Cite

The permeability of murine cauda epididymidal spermatozoa was determined from the swelling caused by penetrating agents at isotonicity, which lies between 422 and 530 mmol/kg. Spermatozoa were permeable to a range of solutes with size !200 Da. Relative entry rates of cryoprotective agents (CPAs) were ethylene glycolzDMSOOpropane-1,2-diolOglycerolOpropane-1,3-diol. More polar compounds including major epididymal secretions were impermeant. None of the compounds entered spermatozoa through quininesensitive channels; rather, quinine increased the size of solute-swollen spermatozoa, suggesting that regulatory volume decrease and osmolyte loss occurred under these conditions. Volume responses to lowered osmolality revealed a greater volume-regulating ability of spermatozoa from the B6D2F1 strain than the C57BL6 strain. As the former strain displays better post-thaw fertility, their spermatozoa may have greater osmolyte loads enabling them to cope better with osmotic stress. Inadequate volume regulation, due to CPA-induced osmolyte loss, may affect post-thaw fertility. Knowing the permeability towards cryoprotectants will help to make a better choice of CPAs that are less damaging to sperm during cryopreservation. Reproduction (2008) 135 625-633

show abstract

“…Cryoprotectants are included in cryopreservation medium to reduce the physical and chemical stresses derived from cooling, freezing and thawing of sperm cells (Gao et al, 1997;Purdy, 2006). Cryoprotectants are classified as either penetrating or non penetrating.…”

Section: Cryoprotectantsmentioning

confidence: 99%