Induction of physiological acrosome reactions in caput epididymal spermatozoa of mice

Biegler, B; Aarons, David; George, B. C.; Poirier, Gary R.

doi:10.1530/jrf.0.1000219

Cited by 15 publications

(4 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This latter suggestion is consistent with a previous study performed on macaque sperm (Yeung et al, 1996) in which the caput epididymal sperm failed to undergo AR, corpus epididymal sperm displayed a low percentage of AR, and the cauda epididymal sperm showed a high percentage of AR following calcium ionophore treatment. The sperm from different parts of the ram (Williams et al, 1991) and human (Yeung et al, 1997) epididymis showed similar results regarding AR to calcium ionophore treatment but the same was not true in the mouse (Biegler et al, 1994). This demonstrates that, in some species, the sperm has to reach a certain maturational stage before it can respond to the induced Ca 2 in¯ux and undergo AR.…”

Section: Discussionmentioning

confidence: 84%

Induction of the acrosome reaction in dog sperm cells is dependent on epididymal maturation: The generation of a functional progesterone receptor is involved

et al. 2001

View full text Add to dashboard Cite

In the current study we investigated the progesterone receptor exposure on the sperm from the testis and different parts of the epididymis, the relation to the sperm maturation stage, the functionality of the progesterone receptor and the capacity of sperm to undergo acrosome reaction. Exposed progesterone receptors on spermatozoa were detected using Progesterone–BSA conjugate labeled with fluorescein isothiocyanate (P‐BSA‐FITC) or a monoclonal antibody against progesterone receptor, C‐262. Either progesterone or calcium ionophore was used to induce acrosome reaction. A high percentage (69 ± 8%; mean ± SD) of spermatozoa from the cauda epididymis showed P‐BSA‐FITC labeling at the onset of incubation, whereas only 0.1 ± 1 and 4 ± 2%, of spermatozoa from the testes, caput, and corpus epididymis, respectively, were labeled. There was no significant increase in P‐BSA‐FITC binding during the course of a 6 hr incubation. Treatment with either 10 μM progesterone or 5 μM calcium ionophore induced acrosome reaction in cauda epididymal sperm but not in testicular sperm, caput or corpus epipidymal sperm. It is concluded that the matured sperm of the dog from cauda epididymis and freshly ejaculated sperm demonstrate a functional membrane‐bound progesterone receptor while less matured spermatozoa from the testicle, caput, and corpus epididymis fail to demonstrate such a receptor. Acrosome reaction of dog sperm can be induced using either progesterone or calcium ionophore; however, the maturation stages of spermatozoa influence this occurrence. Mol. Reprod. Dev. 58:451–459, 2001. © 2001 Wiley‐Liss, Inc.

show abstract

Section: Discussionmentioning

confidence: 84%

Induction of the acrosome reaction in dog sperm cells is dependent on epididymal maturation: The generation of a functional progesterone receptor is involved

et al. 2001

View full text Add to dashboard Cite

show abstract

“…This protease inhibitor seems to be implicated in the maintenance of sperm viability and fertilizing capacity in vitro (Moore and Akhondi, 1996;Moore, 1998). In addition, such inhibitors were proposed to prevent the degradation of viable spermatozoa by proteases released from dead cells, or could be decapacitation factors that modify or mask membrane epitopes involved in zona pellucida binding or the acrosome reaction (Biegler et al, 1994).…”

Section: Discussionmentioning

confidence: 99%

Characterization of secretory proteins from cultured cauda epididymal cells that significantly sustain bovine sperm motility in vitro

Reyes‐Moreno

Boilard

Sullivan

et al. 2002

Molecular Reproduction Devel

View full text Add to dashboard Cite

Epididymis provides a safe environment in which stored-spermatozoa could survive for days before ejaculation. In vitro studies suggested that epididymal proteins seem to be implicated in sperm survival during coincubation with cultured epididymal cells. This study was basically designed to confirm if secretory proteins from bovine epididymal cell cultures provide sperm protection against rapid loss of sperm motility in vitro. Bovine spermatozoa were incubated in conditioned media (CM), which were prepared from cultured cauda epididymal cell (CEC). Motion parameters were recorded using a computer-assisted sperm analyzer. Sperm-free protein extracts from CM were fractionated by ultrafiltration through a 10-kDa cut off membrane. A significantly positive effect on sperm motility was observed when spermatozoa were incubated in CM (54 +/- 4%) and CM > 10 kDa (57 +/- 4%) compared to CM < 10-kDa fraction (30 +/- 3%) or fresh media (34 +/- 3%), after a 6-hr incubation period. This beneficial effect on sperm motility was abolished when the CM > 10-kDa fraction was heat-treated at 100 degrees C for 10 min. The CM > 10 kDa fraction provides factors that remained active even though spermatozoa were washed twice after a 2-hr preincubation period. To identify potential beneficial factors, bovine spermatozoa were incubated with radiolabeled proteins obtained using (35)S-methionine in culture medium. SDS-PAGE analysis of proteins extracted from CM-preincubated spermatozoa revealed the presence of a 42-kDa protein strongly associated to the sperm surface. This 42-kDa spot was trypsin-digested and identified by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) as a protein homologue to a 35-kDa bovine estrogen-sulfotransferase. This protein can play a role in epididymal biology and sperm function. Taken together, these results suggest that specific epididymal proteins can be implicated in the sperm protection in vitro, and can be characterized in our cell culture system.

show abstract

“…There are a number of claims that the epididymis may not be essential for sperm maturation in mammals. Three reports show that spermatozoa from the caput epididymis of the mouse can bind to the zona pellucida of the oocyte provided that the spermatozoa are both capacitated and washed before incubation (McLaughlin & Shur, 1987;Kawai et al, 1991;Biegler et al, 1994). However, many of the spermatozoa in the samples studied would have already been exposed to much of the epididymis as they were isolated from most of the caput epididymis, and this constitutes 3 of the 5 histologically distinct segments in the mouse epididymis (Abe et al, 1983).…”

Section: Sperm Maturation In the Mammalian Epididymismentioning

confidence: 99%

To store or mature spermatozoa? The primary role of the epididymis

1999

View full text Add to dashboard Cite

The function of the epididymis is considered in the context that it is necessary to transport spermatozoa for internal fertilization, but is also an adaptation involved in the competition between males to achieve paternity. Post-testicular sperm maturation and storage occur in lower vertebrates, such as the chondrichthyes, in which sperm storage is essential due to the slow rate of spermatogenesis. These roles persist in higher vertebrates, including mammals. However, they are less important in certain birds, in which the rate of sperm production by the testes is sufficient to supply enough spermatozoa to cope with the demands of a competitive mating system. There is no evidence for mammals, other than humans, that spermatozoa can achieve the capacity to fertilize an ovum without passing through some of the proximal epididymis. Storage of spermatozoa in the epididymis is probably not essential for a male to achieve conception in a protected mating system, but is very important in a competitive mating system. There is some variation between species in the magnitude of the epididymal storage region. This is related to the descent of the epididymides (and testes) into a scrotal sac in some species and/or the demands of the mating system in other species. The claims that humans are not dependent on post-testicular sperm maturation and storage need to be qualified, as they are based on studies of abnormal tracts and tests of fertility which are not rigorous. Nevertheless, the claims are of considerable clinical significance and may indicate that humans are less dependent on post-testicular sperm maturation and storage than other mammals. This may be an adaptation of the testes and epididymides to the scrotal conditions of modern man or a response to changing environmental factors.

show abstract

Induction of physiological acrosome reactions in caput epididymal spermatozoa of mice

Cited by 15 publications

References 3 publications

Induction of the acrosome reaction in dog sperm cells is dependent on epididymal maturation: The generation of a functional progesterone receptor is involved

Induction of the acrosome reaction in dog sperm cells is dependent on epididymal maturation: The generation of a functional progesterone receptor is involved

Characterization of secretory proteins from cultured cauda epididymal cells that significantly sustain bovine sperm motility in vitro

To store or mature spermatozoa? The primary role of the epididymis

Contact Info

Product

Resources

About