Carnitines are important conditionally essential nutrients in the organism, with extensive physiological functions, and highly concentrated in the epididymis and sperm. Carnitines play an important role not only in initiating sperm motility, promoting sperm maturation and enhancing sperm fertilizing, but also in regulating Sertoli cell function, protecting sperm against oxidative damage, reducing apoptosis of spermatogenic cell and inhibiting sperm aggregation. Accordingly, the objective of this review is to summarize the multifunctional roles of carnitine in male reproduction.
Animals ; Carnitine ; physiology ; Humans ; Male ; Mice ; Rats ; Sperm Count ; Sperm Maturation ; physiology ; Sperm Motility ; physiology ; Spermatozoa ; physiology ; Testis ; physiology

OBJECTIVETo study the effect of successive ejaculation on semen analysis parameters in normal men.

METHODSEight ejaculates were collected at daily intervals from 8 normal men. The semen parameters were analyzed according to WHO laboratory manual for the examination of human semen and sperm-cervical mucus interaction.

RESULTSThe semen volumes and total sperm counts decreased gradually day by day, significantly lower from the 5th to the 8th day than the 1st (P < 0.01). The sperm densities also declined day by day, but not significantly. The sperm viability and motility (a + b grade) presented an increasing trend, but with no significance except on the 7th day.

CONCLUSIONWith the increase of the ejaculatory frequency, human semen volumes and the total counts significantly decrease, while sperm viability and motility gradually increase. Successive ejaculation does not affect the quality of human semen.

Adult ; Ejaculation ; physiology ; Humans ; Male ; Semen ; physiology ; Sperm Count ; Sperm Motility

To investigate the influences of sperm quality on the zygotes and embryos development, as the role of the paternal factor in early human embryogenesis is gaining more attention because of the application of techniques such as intracytoplasmic sperm injection (ICSI) for the treatment of men infertility. 136 infertility couples with men factors (Group I ) were included from May 2002 to January 2001. One hundred and seventy-two infertility couples with tube factors (Group II) served as controls. The sperm parameters, gemmates and embryos quality, implantation rate and pregnant rate in both groups were analyzed. It was found that there was no significant differences in the number of oocytes retrieved, the fertilization rate and number of embryos transferred between two groups. Sperm concentration, percentage of motile sperm and percentage of sperm with normal morphology were significantly lower in group I than in group II (P < 0.01). The proportion of good quality zygotes and good quality embryos were significantly lower in the male infertility group than in the tubal disease group (P < 0.05). Implantation rate and pregnancy rate were similar in two groups. It was concluded that spermatozoa is involved in the embryo quality, even in the early stages of development, which limited the treatment potency of IVF procedure.
Embryo Transfer ; Embryonic Development ; Fertilization in Vitro ; Infertility, Male ; Sperm Count ; Sperm Injections, Intracytoplasmic ; Sperm Motility/*physiology ; *Spermatozoa/cytology ; *Spermatozoa/physiology

The sperm plasma membrane is rich in polyunsaturated fatty acids and a variety of proteins, and its function is associated with sperm capacitation, acrosome reaction and sperm-egg fusion. Sperm fertilizability can be predicted by detecting the function of the sperm plasma membrane, which is performed mainly with the following five techniques: sperm hypoosmotic swelling test, Eosin gamma water test, sperm membrane lipid peroxidation determination, seminal plasma superoxide dismutase determination, and flow cytometry. The evaluation of the function of sperm plasma membrane can be applied in detecting semen quality, selecting semen centrifugation, assessing the quality and fertilizability of sex-sorted sperm, improving cryopreservation, and guiding the optimization of intracytoplasmic sperm injection. This review presents an update on the principles, methods and steps of the detection of sperm plasma membrane function, as well as an overview of its status quo and application.
Cell Membrane ; physiology ; Flow Cytometry ; Humans ; Male ; Semen Analysis ; Semen Preservation ; Sperm Capacitation ; Sperm Injections, Intracytoplasmic ; Sperm Motility ; Spermatozoa ; physiology

The present review is intended to give an outlook on the relationship between male reproduction and seminal vesicles, which are an important subsidiary gonad of males and play a key role in male fertility process. Seminal vesicle secretion is important for semen coagulation and may promote sperm motility, increase stability of sperm chromatin, and suppress the immune activity in the female reproductive tract. Furthermore, the sexual function of males is closely related to the swelling degree of seminal vesicles. The abnormal function of seminal vesicles may give rise to sexual dysfunction and infertility of males.
Fertility ; physiology ; Humans ; Infertility, Male ; physiopathology ; Male ; Reproduction ; physiology ; Seminal Vesicles ; physiology ; physiopathology ; Sperm Count ; Sperm Motility ; physiology

Sperm cryopreservation has revolutionized the field of assisted reproduction. However, it causes cryodamage to the structure and function of spermatozoa during the freezing-thawing process. Optimization of sperm cryopreservation is necessary for the preservation of male fertility. Cryodamage can be reduced effectively by such methods as improvement of semen quality before freezing, spermatozoal selection, addition of optimal cryoprotectants and application of appropriate thawing techniques. Recent studies focus on cryobiology, improvement of freezing-thawing methods, especially for poor quality semen, and evaluation criteria for post-thaw spermatozoa.
Cryopreservation ; methods ; Humans ; Male ; Semen Preservation ; methods ; Sperm Count ; Sperm Motility ; Spermatozoa ; cytology ; physiology

Sperm membrane fluidity is one of the causes of male infertility, and it is thought to be related with temperature, reactive oxygen species, oxygen free radicals, anti-sperm antibodies, stilbestrol, and fenvalerate. A deeper insight into the influencing factors of sperm membrane fluidity is of vital importance for in vitro sperm preservation, revival of frozen-thawed sperm, in vitro fertilization and management of male infertility.
Humans ; Infertility, Male ; Male ; Membrane Fluidity ; Semen Preservation ; Sperm Motility ; Sperm-Ovum Interactions ; Spermatozoa ; physiology

This article reviews the recent literature on sperm morphology and attempts to illuminate the important value of sperm morphology for evaluating man fertility, with a survey of the present status of sperm morphology analysis techniques and the relationship between sperm morphology and sperm function tests. Sperm morphology analysis, although its techniques need to be further improved, is proved of great value for its significant correlation with sperm function and as a predictor in assisted reproduction.
Humans ; Infertility, Male ; Male ; Sperm Count ; Sperm Motility ; Spermatozoa ; pathology ; physiology ; Staining and Labeling

The clinical effects of acupuncture on idiopathic male infertility in sperm parameter and on therapeutic results in assisted reproductive technology were investigated. 22 patients failed in intracytoplasmic sperm injection (ICSI) with idiopathic male infertility were treated with acupuncture twice weekly for 8 weeks, followed by ICSI treatment again. The sperm concentration, motility, morphology, fertilization rates and embryo quality were observed. Quick sperm motility after acupuncture (18.3% +/- 9.6%) was significantly improved as compared with that before treatment (11.0% +/- 7.5%, P < 0.01). The normal sperm ratio was increased after acupuncture (21.1% +/- 10.4% vs 16.2% +/- 8.2%, P < 0.05). The fertilization rates after acupuncture (66.2%) were obviously higher than that before treatment (40.2%, P < 0.01). There was no significant difference in sperm concentration and general sperm motility between before and after acupuncture. The embryo quality after acupuncture was improved, but the difference between them was not significant (P > 0.05). Acupuncture can improve sperm quality and fertilization rates in assisted reproductive technology.
*Acupuncture Therapy ; Combined Modality Therapy ; Infertility, Male/*therapy ; Semen ; *Sperm Injections, Intracytoplasmic ; *Sperm Motility ; Spermatozoa/physiology

OBJECTIVETo investigate the influence of long-term anoxic exposure on the sperm function of male adults at different altitudes.

METHODSA total of 28 male adults that had stayed at the altitude of 5 340 m for 1-3 years were included as a high-altitude group (HAG), 34 at the mean altitude of 3 800 m for 2-5 years as a middle-altitude group (MAG) and 31 permanently at the altitude of 1 300 m as controls. Semen specimens were collected and the real-time semen analysis was performed by using computer-assisted semen analysis (CASA) system.

RESULTSThe sperm density, VCL, VSL, VAP and LIN in the HAG were (51.12 +/- 14.61) x 10(6)/ ml, (48.17 +/- 13. 52) microm/s, (32.64 +/- 6.70) microm/s, (41.21 +/- 9.32) microm/s and 52.24 +/- 8.14, respectively, significantly lower than those of the control (P < 0.01 or P < 0.05). Compared with the control group, there was a progressive decrease in sperm concentration, sperm motility rate, VSL, VCL, LIN, VAP and ALH in the MAG.

CONCLUSIONThe higher the altitude, the more obvious was the negative effect of anoxic exposure on the sperm function of male adults.

Adult ; Altitude ; Control Groups ; Diagnosis, Computer-Assisted ; Humans ; Male ; Sperm Count ; Sperm Motility ; Spermatozoa ; physiology