Cytosolic calcium levels in spermatozoa are modulated differently in healthy subjects and patients with varicocele

Fertil Steril. 2006 Jan;85(1):144-8. doi: 10.1016/j.fertnstert.2005.07.1293.

Abstract

Objective: To study parameters connected to fertility in the semen of patients with varicocele.

Design: We examine the ability of spermatozoa obtained from patients with varicocele to respond with an increase of cytosolic Ca2+ ([Ca2+]i) to some stimuli that are connected with spermatozoa activation.

Setting: An academic research environment.

Patient(s): Ten healthy volunteer donors and 10 patients affected by II or III grade left varicocele.

Intervention(s): Spermatozoa and prostasomes (vesicles of prostatic origin obtained from semen) were prepared according to standard procedures. Spermatozoa were stimulated with 1 microM P. The [Ca2+]i was evaluated with the FURA II method.

Main outcome measure(s): The level of [Ca2+]i.

Result(s): In resting cells, the level of [Ca2+]i was 120 +/-15 nmol/L (10 determinations). This value increases by > or =100 nmol/L upon stimulation with P. No difference was observed between spermatozoa obtained from healthy donors or from patients with varicocele. S-nitrosocysteine, a nitric oxide donor, and the fusion between spermatozoa and prostasomes increased the effect of P on [Ca2+]i in control spermatozoa but not in spermatozoa obtained from patients with varicocele.

Conclusion(s): Different responsiveness of varicocele patients' spermatozoa to S-nitrosocysteine and/or to fusion with prostasomes may be among the possible causes of reduced fertility.

MeSH terms

  • Adult
  • Calcium / metabolism*
  • Cysteine / analogs & derivatives
  • Cysteine / chemical synthesis
  • Cysteine / metabolism
  • Cytosol / metabolism
  • Fertility
  • Humans
  • Infertility, Male / metabolism
  • Infertility, Male / pathology
  • Male
  • Nitric Oxide / metabolism
  • Prostate / metabolism
  • Prostate / pathology
  • S-Nitrosothiols / chemical synthesis
  • S-Nitrosothiols / metabolism
  • Spermatozoa / metabolism*
  • Varicocele / metabolism*
  • Varicocele / pathology*

Substances

  • S-Nitrosothiols
  • Nitric Oxide
  • S-nitrosocysteine
  • Cysteine
  • Calcium