Skip to main content
PMC home page
Biochemical Journal logoLink to Biochemical Journal
. 2003 Jun 1;372(Pt 2):407–417. doi: 10.1042/BJ20021560

Encoding of progesterone stimulus intensity by intracellular [Ca2+] ([Ca2+]i) in human spermatozoa.

Claire V Harper 1, Jackson C Kirkman-Brown 1, Christopher L R Barratt 1, Stephen J Publicover 1
PMCID: PMC1223411  PMID: 12614198

Abstract

Progesterone induces a biphasic Ca(2+) influx and consequent acrosome reaction in human spermatozoa. We have used two procedures to vary the stimulus (dosage and prior receptor desensitization) to investigate the encoding of stimulus strength by intracellular [Ca(2+)] ([Ca(2+)](i)). Acrosome reaction and amplitude (but not kinetics) of the transient [Ca(2+)](i) response (population measurement) showed sigmoidal dose sensitivity over the range 0.3 nM-3 microM, saturating at approximately 300 nM (ED(50) approximately 30 nM). The amplitude of the sustained response saturated at 3 microM. Single-cell imaging showed that the amplitudes of both transient and sustained [Ca(2+)](i) responses were highly dose-dependent, but that their frequency of occurrence and kinetics were largely dose-independent. Fluorimetric measurements confirmed that progesterone-induced [Ca(2+)](i) influx was subject to desensitization, with second and subsequent applications of 3 microM progesterone being ineffective. However, sequential additions of 3 nM, 30 nM and 3 microM progesterone generated transient [Ca(2+)](i) responses at each concentration, the amplitude and duration of the response to 3 microM progesterone being reduced compared with non-pretreated cells. Single-cell imaging revealed that pretreatment had no effect on the proportion of responsive cells, but single-cell responses, similarly to population responses, were smaller and markedly reduced in duration, consistent with an effect of desensitization on a late component of the [Ca(2+)](i) transient. We conclude that the strength of the progesterone stimulus, when varied by dosage or by desensitization, is encoded by an analogue [Ca(2+)](i) signal. Dose dependency of the acrosome reaction is therefore determined not by the number of progesterone-responsive cells but by variation in the probability of exocytosis in a 'constant' responsive population.

Full Text

The Full Text of this article is available as a PDF (287.4 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Aitken R. J., Buckingham D. W., Irvine D. S. The extragenomic action of progesterone on human spermatozoa: evidence for a ubiquitous response that is rapidly down-regulated. Endocrinology. 1996 Sep;137(9):3999–4009. doi: 10.1210/endo.137.9.8756577. [DOI] [PubMed] [Google Scholar]
  2. Aitken R. J. Molecular mechanisms regulating human sperm function. Mol Hum Reprod. 1997 Mar;3(3):169–173. doi: 10.1093/molehr/3.3.169. [DOI] [PubMed] [Google Scholar]
  3. Baldi E., Casano R., Falsetti C., Krausz C., Maggi M., Forti G. Intracellular calcium accumulation and responsiveness to progesterone in capacitating human spermatozoa. J Androl. 1991 Sep-Oct;12(5):323–330. [PubMed] [Google Scholar]
  4. Baldi E., Luconi M., Bonaccorsi L., Forti G. Nongenomic effects of progesterone on spermatozoa: mechanisms of signal transduction and clinical implications. Front Biosci. 1998 Nov 1;3:D1051–D1059. doi: 10.2741/a345. [DOI] [PubMed] [Google Scholar]
  5. Bendahmane Malika, Zeng Hai-Tao, Tulsiani Daulat R. P. Assessment of acrosomal status in rat spermatozoa: studies on carbohydrate and non-carbohydrate agonists. Arch Biochem Biophys. 2002 Aug 1;404(1):38–47. doi: 10.1016/s0003-9861(02)00278-3. [DOI] [PubMed] [Google Scholar]
  6. Berridge M. J., Bootman M. D., Lipp P. Calcium--a life and death signal. Nature. 1998 Oct 15;395(6703):645–648. doi: 10.1038/27094. [DOI] [PubMed] [Google Scholar]
  7. Bers Donald M. Sarcoplasmic reticulum Ca release in intact ventricular myocytes. Front Biosci. 2002 Jul 1;7:d1697–d1711. doi: 10.2741/A873. [DOI] [PubMed] [Google Scholar]
  8. Blackmore P. F., Beebe S. J., Danforth D. R., Alexander N. Progesterone and 17 alpha-hydroxyprogesterone. Novel stimulators of calcium influx in human sperm. J Biol Chem. 1990 Jan 25;265(3):1376–1380. [PubMed] [Google Scholar]
  9. Blackmore P. F., Eisoldt S. The neoglycoprotein mannose-bovine serum albumin, but not progesterone, activates T-type calcium channels in human spermatozoa. Mol Hum Reprod. 1999 Jun;5(6):498–506. doi: 10.1093/molehr/5.6.498. [DOI] [PubMed] [Google Scholar]
  10. Bonaccorsi L., Luconi M., Forti G., Baldi E. Tyrosine kinase inhibition reduces the plateau phase of the calcium increase in response to progesterone in human sperm. FEBS Lett. 1995 May 1;364(1):83–86. doi: 10.1016/0014-5793(95)00369-k. [DOI] [PubMed] [Google Scholar]
  11. Calogero A. E., Burrello N., Ferrara E., Hall J., Fishel S., D'Agata R. Gamma-aminobutyric acid (GABA) A and B receptors mediate the stimulatory effects of GABA on the human sperm acrosome reaction: interaction with progesterone. Fertil Steril. 1999 May;71(5):930–936. doi: 10.1016/s0015-0282(99)00063-1. [DOI] [PubMed] [Google Scholar]
  12. Foresta C., Rossato M., Di Virgilio F. Ion fluxes through the progesterone-activated channel of the sperm plasma membrane. Biochem J. 1993 Aug 15;294(Pt 1):279–283. doi: 10.1042/bj2940279. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Garcia M. A., Meizel S. Importance of sodium ion to the progesterone-initiated acrosome reaction in human sperm. Mol Reprod Dev. 1996 Dec;45(4):513–520. doi: 10.1002/(SICI)1098-2795(199612)45:4<513::AID-MRD14>3.0.CO;2-X. [DOI] [PubMed] [Google Scholar]
  14. Grynkiewicz G., Poenie M., Tsien R. Y. A new generation of Ca2+ indicators with greatly improved fluorescence properties. J Biol Chem. 1985 Mar 25;260(6):3440–3450. [PubMed] [Google Scholar]
  15. Hansen M., Boitano S., Dirksen E. R., Sanderson M. J. Intercellular calcium signaling induced by extracellular adenosine 5'-triphosphate and mechanical stimulation in airway epithelial cells. J Cell Sci. 1993 Dec;106(Pt 4):995–1004. doi: 10.1242/jcs.106.4.995. [DOI] [PubMed] [Google Scholar]
  16. Kirkman-Brown J. C., Bray C., Stewart P. M., Barratt C. L., Publicover S. J. Biphasic elevation of [Ca(2+)](i) in individual human spermatozoa exposed to progesterone. Dev Biol. 2000 Jun 15;222(2):326–335. doi: 10.1006/dbio.2000.9729. [DOI] [PubMed] [Google Scholar]
  17. Kirkman-Brown Jackson C., Punt Emma L., Barratt Christopher L. R., Publicover Stephen J. Zona pellucida and progesterone-induced Ca2+ signaling and acrosome reaction in human spermatozoa. J Androl. 2002 May-Jun;23(3):306–315. [PubMed] [Google Scholar]
  18. Krausz C., Bonaccorsi L., Maggio P., Luconi M., Criscuoli L., Fuzzi B., Pellegrini S., Forti G., Baldi E. Two functional assays of sperm responsiveness to progesterone and their predictive values in in-vitro fertilization. Hum Reprod. 1996 Aug;11(8):1661–1667. doi: 10.1093/oxfordjournals.humrep.a019466. [DOI] [PubMed] [Google Scholar]
  19. Kumar S., Ying Y. K., Hong P., Maddaiah V. T. Potassium increases intracellular calcium simulating progesterone action in human sperm. Arch Androl. 2000 Mar-Apr;44(2):93–101. doi: 10.1080/014850100262254. [DOI] [PubMed] [Google Scholar]
  20. Li Y., Holtzclaw L. A., Russell J. T. Müller cell Ca2+ waves evoked by purinergic receptor agonists in slices of rat retina. J Neurophysiol. 2001 Feb;85(2):986–994. doi: 10.1152/jn.2001.85.2.986. [DOI] [PubMed] [Google Scholar]
  21. Luconi M., Bonaccorsi L., Maggi M., Pecchioli P., Krausz C., Forti G., Baldi E. Identification and characterization of functional nongenomic progesterone receptors on human sperm membrane. J Clin Endocrinol Metab. 1998 Mar;83(3):877–885. doi: 10.1210/jcem.83.3.4672. [DOI] [PubMed] [Google Scholar]
  22. Meizel S., Turner K. O., Nuccitelli R. Progesterone triggers a wave of increased free calcium during the human sperm acrosome reaction. Dev Biol. 1997 Feb 1;182(1):67–75. doi: 10.1006/dbio.1997.8477. [DOI] [PubMed] [Google Scholar]
  23. Melendrez C. S., Meizel S. Studies of porcine and human sperm suggesting a role for a sperm glycine receptor/Cl- channel in the zona pellucida-initiated acrosome reaction. Biol Reprod. 1995 Sep;53(3):676–683. doi: 10.1095/biolreprod53.3.676. [DOI] [PubMed] [Google Scholar]
  24. Miyazaki S. Inositol trisphosphate receptor mediated spatiotemporal calcium signalling. Curr Opin Cell Biol. 1995 Apr;7(2):190–196. doi: 10.1016/0955-0674(95)80027-1. [DOI] [PubMed] [Google Scholar]
  25. Morales P., Llanos M., Gutierrez G., Kohen P., Vigil P., Vantman D. The acrosome reaction-inducing activity of individual human follicular fluid samples is highly variable and is related to the steroid content. Hum Reprod. 1992 May;7(5):646–651. doi: 10.1093/oxfordjournals.humrep.a137712. [DOI] [PubMed] [Google Scholar]
  26. Osman R. A., Andria M. L., Jones A. D., Meizel S. Steroid induced exocytosis: the human sperm acrosome reaction. Biochem Biophys Res Commun. 1989 Apr 28;160(2):828–833. doi: 10.1016/0006-291x(89)92508-4. [DOI] [PubMed] [Google Scholar]
  27. Plant A., McLaughlin E. A., Ford W. C. Intracellular calcium measurements in individual human sperm demonstrate that the majority can respond to progesterone. Fertil Steril. 1995 Dec;64(6):1213–1215. doi: 10.1016/s0015-0282(16)57989-8. [DOI] [PubMed] [Google Scholar]
  28. Saito Y., Kato M., Kobayashi I., Tatemoto K. Effects of bradykinin on the intracellular calcium concentration of pancreatic acinar AR42J cells. Life Sci. 1996;58(18):1569–1574. doi: 10.1016/0024-3205(96)00131-2. [DOI] [PubMed] [Google Scholar]
  29. Sato N., Wang X., Greer M. A. Comparison of ramp and square-wave exposure to thyrotrophin-releasing hormone or depolarizing K+ on cytosolic Ca2+ concentration and prolactin secretion in GH4C1 cells. J Endocrinol. 1994 Jul;142(1):145–152. doi: 10.1677/joe.0.1420145. [DOI] [PubMed] [Google Scholar]
  30. Schaefer M., Habenicht U. F., Bräutigam M., Gudermann T. Steroidal sigma receptor ligands affect signaling pathways in human spermatozoa. Biol Reprod. 2000 Jul;63(1):57–63. doi: 10.1095/biolreprod63.1.57. [DOI] [PubMed] [Google Scholar]
  31. Schomerus C., Laedtke E., Korf H. W. Calcium responses of isolated, immunocytochemically identified rat pinealocytes to noradrenergic, cholinergic and vasopressinergic stimulations. Neurochem Int. 1995 Aug;27(2):163–175. doi: 10.1016/0197-0186(95)00029-8. [DOI] [PubMed] [Google Scholar]
  32. Somanath PR, Suraj K, Gandhi KK. Caprine sperm acrosome reaction: promotion by progesterone and homologous zona pellucida. Small Rumin Res. 2000 Aug 1;37(3):279–286. doi: 10.1016/s0921-4488(99)00148-0. [DOI] [PubMed] [Google Scholar]
  33. Thomas P., Meizel S. Phosphatidylinositol 4,5-bisphosphate hydrolysis in human sperm stimulated with follicular fluid or progesterone is dependent upon Ca2+ influx. Biochem J. 1989 Dec 1;264(2):539–546. doi: 10.1042/bj2640539. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Tosti E., Di Cosmo A., Cuomo A., Di Cristo C., Gragnaniello G. Progesterone induces activation in Octopus vulgaris spermatozoa. Mol Reprod Dev. 2001 May;59(1):97–105. doi: 10.1002/mrd.1011. [DOI] [PubMed] [Google Scholar]
  35. Yang J., Serres C., Philibert D., Robel P., Baulieu E. E., Jouannet P. Progesterone and RU486: opposing effects on human sperm. Proc Natl Acad Sci U S A. 1994 Jan 18;91(2):529–533. doi: 10.1073/pnas.91.2.529. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES