Sperm motility activation in the critically endangered booroolong frog: the effect of medium osmolality and phosphodiesterase inhibitors
Aimee J. Silla, Leesa M. Keogh, Phillip G. Byrne
2017
Reproduction, Fertility and Development
Effective activation of sperm motility is fundamental to successful artificial fertilisation; however, studies investigating optimal procedures in amphibians are lacking. This study found the optimal osmolality of activation media for sperm motility activation and evaluated the effect of phosphodiesterase (PDE) inhibitors on sperm activation and longevity in the critically endangered booroolong frog, Litoria booroolongensis. To assess the effect of medium osmolality (10, 25, 50, 75, 100 and 200
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... mOsmol kg−1) and PDE inhibitors (control, 2.5 mM caffeine, 5 mM caffeine, 2.5 mM pentoxifylline, 5 mM pentoxifylline, 2.5 mM theophylline and 5 mM theophylline) on initial activation, percentage sperm motility and sperm velocity were quantified using computer-assisted sperm analysis. To assess the effect of PDE inhibitors (control, 2.5 mM caffeine and 2.5 mM theophylline) on sperm longevity, percentage motility and velocity were assessed hourly until 10 h after activation. High (>60%) percentage motility was achieved in a broad range of activation-medium osmolalities (10-75 mOsmol kg−1). PDE inhibitors did not have an effect on initial sperm motility or velocity, but caffeine and theophylline improved sperm longevity, significantly increasing motility and velocity at 8, 9 and 10 h after activation. Data also show that sperm longevity in L. booroolongensis is extreme, with spermatozoa remaining motile more than twice as long as those of any other anuran amphibian. Abstract 39 Effective activation of sperm motility is fundamental to successful artificial fertilisation, 40 however studies investigating optimal procedures in amphibians are lacking. This study 41 found the optimal osmolality of activation media for sperm motility activation, and evaluated 42 the effect of phosphodiesterase (PDE)-inhibitors on sperm activation and longevity in the 43 critically endangered booroolong frog, Litoria booroolongensis. To assess the effect of 44 medium osmolality (10, 25, 50, 75, 100 & 200 mOsmol kg -1 ) and PDE -inhibitors (control, 45 2.5mM caffeine, 5mM caffeine, 2.5mM pentoxifylline, 5mM pentoxifylline, 2.5mM 46 theophylline & 5mM theophylline) on initial activation, sperm motility (%) and sperm 47 velocity (VCL) were quantified using computer assisted sperm analysis (CASA). To assess 48 the effect of PDE-inhibitors (control, 2.5mM caffeine and 2.5mM theophylline) on sperm 49 longevity, percentage motility and velocity were assessed hourly until 10 hours post-50 activation. High (>60%) percent motility was achieved in a broad range of activation-medium 51 osmolalities (10 -75 mOsmol kg -1 ). PDE-inhibitors did not have an effect on initial sperm 52 motility or velocity, but caffeine and theophylline improved sperm longevity, significantly 53 increasing motility and velocity at 8, 9, and 10 hours post-activation. Data also show that 54 sperm longevity in L. booroolongensis is extreme, with sperm remaining motile more than 55 twice the duration of any other anuran amphibian. 56 57 58
doi:10.1071/rd17012
pmid:28359014
fatcat:elv7tozrqve2hehnk3dmpluuwa