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Query: UMLS:C0231530 (twitching)
 2,043 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The motility of spermatozoa from the head and tail of the epididymis in bulls was studied. Qualitatively and quantitatively, the motility of spermatozoa from the cauda was distinctly better than that from the caput. It was possible to achieve a highly significant increase in the motility of epididymal spermatozoa from the caput as well as the cauda area using caffeine or a caffeine-kallikrein mixture. Above all, motility stimulants improved the local motility of the epididymal spermatozoa as compared to twitching and progressive motility. The motility of caudal spermatozoa was increased by 100%, corresponding to local movement of 59% of the total number of sperm cells. It was possible to demonstrate an increase in the almost totally absent motility of the caput spermatozoa to 27% local motility. Application of kallikrein without addition of kininogens led to no significant change in spermatozoa motility. By the addition of caffeine, it was possible to increase the motility of minipig epididymal spermatozoa taken by puncture from alloplastic spermatoceles significantly. In 23 aspirates, a prompt increase in the percentage of locally motile "spermatocele spermatozoa" from 12% to 23.5% was observed.
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PMID:How to increase the motility of spermatozoa from the epididymis of bulls and alloplastic spermatoceles in minipigs. 656 56

Mouse spermatozoa recovered from the caput, corpus, or cauda epididymidis were examined for their ability to bind the vitro to zonae pellucidae. Since spermatozoa from the caput epididymidis do not display progressive motility as compared with more mature spermatozoa, direct comparison of the different sperm populations may not measure zona binding ability validly. To equalize the motile properties of the spermatozoa, a method was developed to immobilize vigorously motile corpus and cauda spermatozoa. Reversible immobilization was achieved by incubation in 25 microM La3+ which resulted in a twitching, nonprogressive type of motility. La3+ incubation did not appear to affect the spermatozoa adversely, since vigorous motility (equivalent to the controls) of corpus and cauda sperm was displayed upon subsequent incubation in standard La3+-free culture medium. Moreover, cauda spermatozoa preincubated for 90 min in La3+ displayed levels of fertilization in vitro equivalent to their control counterparts. Using this La3+-immobilization technique, the zona binding ability of the different sperm population could be assayed. Gamete collision was insured under these conditions by shaking the gamete-containing dishes at 100 cycles/min. Regardless of the extent of sperm motility, a similar zona-binding pattern emerged: cauda sperm bound in high numbers, corpus sperm bound at some intermediate level (an average of 24% of cauda binding level), and caput sperm bound rarely (2% of cauda binding level). Thus it appears that, for mouse spermatozoa, the onset of fertility during epididymal transit parallels the ability to bind to zonae pellucidae. Unlike the interaction between spermatozoa and zonae, La3+ was unable to support sperm binding in to egg plasma membrane, supporting the view that mouse sperm may have different sites for interaction with the zonae pellucida and the egg plasma membrane.
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PMID:Development of the ability to bind to zonae pellucidae during epididymal maturation: reversible immobilization of mouse-spermatozoa by lanthanum. 720 Aug 7

For men with uncorrectable obstructive azoospermia, their only hope of fathering a child is microsurgical epididymal sperm aspiration (MESA) combined with in vitro fertilization (IVF). In 1988, proximal epididymal sperm were demonstrated to have better motility than senescent sperm in the distal epididymis, and it was thought that retrieval of motile sperm from the proximal epididymis would yield reliable fertilization and pregnancy rates after conventional IVF. However, the results to date have been poor, and although a minority of patients achieved good fertilization rates with IVF, the vast majority (81%) had consistently poor or no fertilization and the pregnancy rate averaged only 9%. Recently, intracytoplasmic sperm injection (ICSI) has been successfully used to achieve fertilization and pregnancies for patients with extreme oligoasthenozoospermia. ICSI has therefore been applied to cases of obstructive azoospermia and, in this report, 67 MESA-IVF cases are compared with 72 MESA-ICSI cases. The principle that motile sperm from the proximal segments of the epididymis should be used for ICSI was followed, although in the most severe cases in which there was an absence of the epididymis (or absence of sperm in the epididymis), testicular sperm were obtained from macerated testicular biopsies. These sperm only exhibited a weak, twitching motion. In 72 consecutive MESA cases, ICSI resulted in fertilization and normal embryos for transfer in 90% of the cases, with an overall fertilization rate of 46%, a cleavage rate of 68%, and ongoing or delivered pregnancy rates of 46% per transfer and 42% per cycle. The pregnancy and take-home baby rates increased from 9% and 4.5% with IVF to 53% and 42% with ICSI. There were no differences between the results for fresh epididymal, frozen epididymal or testicular sperm, and the number of eggs collected did not affect the outcome. The results were also unaffected by the aetiology of the obstruction such as congenital absence of the vas deferens or failed vasoepididymostomy. The only significant factor which affected the pregnancy rate was female age. It is concluded that although complex mechanisms involving epididymal transport may be beneficial for conventional fertilization of human oocytes (in vivo or in vitro), none of these mechanisms are required for fertilization after ICSI. Given the excellent results with epididymal and testicular sperm, ICSI is obligatory for all future MESA patients. Finally, the use of ICSI with testicular sperm from men with non-obstructive azoospermia is also discussed.
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PMID:Fertilizing capacity of epididymal and testicular sperm using intracytoplasmic sperm injection (ICSI). 748 Aug 47

Intracytoplasmic sperm injection (ICSI) has been successful in cases of extreme oligoasthenozoospermia in achieving pregnancies via in-vitro fertilization (IVF) with the lowest imaginable sperm counts. In azoospermia caused by congenital bilateral absence of the vas deferens (CBAVD), it has been shown that epididymal spermatozoa can be retrieved in large numbers, but fertilization rates using conventional IVF are low. Furthermore, no fertilization has ever been possible using testicular spermatozoa with conventional IVF. In the most extreme case of absence of the epididymis, spermatozoa can only be retrieved from macerated testicular biopsy specimens. In such cases, all that can be seen are free-floating Sertoli cells with many spermatids attached, and only occasional spermatozoa per high power field which have only the barest, occasional, slightly twitching motion. The objective of the present study was to determine whether ICSI could achieve better results than conventional IVF with microsurgical aspiration of spermatozoa (MESA). ICSI (using epididymal or testicular spermatozoa) from men with CBAVD or irreparable obstructive azoospermia, achieved good fertilization and normal embryos in 82% of cases, compared to 19% with conventional IVF. There was an overall fertilization rate of 45%, with 85% progressing to normally cleaving embryos using ICSI, compared to 6.9% using conventional IVF. The pregnancy rate with ICSI/MESA was 47% per stimulated cycle (normal delivery rate was 30%), compared to 4.5% with conventional IVF. These results were achieved in patients who had consistently failed to fertilize in previous cycles with MESA and conventional IVF.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Conventional in-vitro fertilization versus intracytoplasmic sperm injection for patients requiring microsurgical sperm aspiration. 867 Dec 92

1. The involvement of alpha 1-adrenoceptor subtypes in adrenergic neurogenic contractions of different type was studied in epididymal and prostatic portions of the rat vas deferens. 2. The adrenergic component of neurogenic contractions was isolated by suramin (300 microM). Twitch-like and tonic contractions were elicited by appropriate pulse patterns of electrical field stimulation, and contractions relying on intracellular calcium mobilization and calcium entry were isolated by means of nifedipine (10 microM) and ryanodine (20 microM), respectively. Increasing concentrations of 2-(2,6-dimethoxyphenoxyethyl)aminomethyl-1,4-benzodioxane (WB 4101), alpha-ethyl-3,4,5-trimethoxy-alpha-(3-((2-(2-methoxyphenoxy)ethyl)- amino)-propyl)benzeneacetonitrile (HV 723), prazosin and 5-methylurapidil progressively, monophasically and with potency decreasing in that order reduced and finally abolished all types of contraction, with one exception: concentration-effect curves of 5-methylurapidil in epididymal segments in the presence of ryanodine levelled off at about 75% inhibition. In the presence of both nifedipine (10 microM) and ryanodine (20 microM), contractions were abolished. 3. Contractions elicited by exogenous noradrenaline were also studied in the presence of either nifedipine 10 microM (prostatic segments) or ryanodine 20 microM (epididymal segments). Increasing concentrations of tamsulosin, WB 4101, benoxathian, HV 723, prazosin, 5-methylurapidil and urapidil progressively, monophasically and with potency decreasing in that order reduced and eventually abolished both kinds of contraction, with two exceptions: in epididymal segments in the presence of ryanodine, the concentration-effect curve of 5-methylurapidil was biphasic and the curve of urapidil levelled off at only partial inhibition. 4. In slices prepared from the prostatic end and preincubated with [3H]-noradrenaline, WB 4101, HV 723, prazosin and 5-methylurapidil, at the highest concentrations tested against neurogenic contractions, increased only slightly the overflow of tritium elicited by trains of 50 pulses at 5 Hz. 5. It is concluded that two alpha l-adrenoceptor subtypes mediate adrenergic neurogenic contractions of rat vas deferens. The main one, pharmacologically alpha 1A, activates both calcium mobilization and entry. In addition there is a second receptor, not previously detected in the vas deferens and not corresponding to any named alpha l subtype, characterized by high and similar affinity for tamsulosin, WB 4101, benoxathian,HV 723 and prazosin and very low affinity for 5-methylurapidil and urapidil, and linked exclusively to calcium entry. Both subtypes and their respective transduction pathways also contribute to contractions elicited by exogenous noradrenaline. An alpha 1B-adrenoceptor-mediated contraction was not found under any experimental conditions.
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PMID:Alpha 1-adrenoceptors and calcium sources in adrenergic neurogenic contractions of rat vas deferens. 791 53