+ Site Statistics
+ Resolve Accession
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
Submit PDF Full TextSubmit PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Sperm motility in the horseshoe crab 4. extracellular ions and intra cellular ph are not mediators of motility initiation

, : Sperm motility in the horseshoe crab 4. extracellular ions and intra cellular ph are not mediators of motility initiation. Gamete Research 6(4): 327-342

Upon dilution into sea water, Limulus spermatozoa undergo a brief flurry of motility (duration < 60 s), after which they are nonmotile until encountering a sperm motility initiating peptide (SMI) that emanates from eggs. Utilizing highly purified SMI extracts and simplified seawater formulations (from which individual ions were deleted), no specific extracellular ion is required for either dilution-initiated or SMI-initiated motility. Deletion of 1 ion (Na+) produced dilution-initiated motility of very long duration (several hours). When motility is initiated by SMI (in normal seawater) there is an increase in intracellular pH (pHi), as indicated by the fluorescent probe, 9-amino acridine; this pHi change is not a trigger for motility. As a more general method examining ion movements, the fluorescent probe diS-C3-(5) was used to qualitatively measure changes in the membrane potential of spermatozoa. Although crude SMI extracts caused membrane depolarization, further purification resulted in an almost complete separation of this activity from SMI, showing that SMI activation is apparently an electroneutral event. (The membrane-depolarizing factor has a MW > 30,000 and does not initiate acrosome reactions.) Experiments utilizing the ionophore A23187 [calcimycin] and Ca+2-blocking agents (verapamil and TMB-8 [8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate]) provided tentative evidence that mobilization of intracellular Ca+2 may be required for motility initiation. Neither changes in pHi nor the influx of specific extracellular ions are direct mediators of SMI-initiated motility; experiments with pharmacologic agents indicate a possible role for intracellular Ca+2.

(PDF 0-2 workdays service)

Order PDF Full Text


Click here to order any other PDF Full Text

Accession: 006461808

PDF Full Text: Submit

Submit PDF Full Text

No spam - Every submission is manually reviewed

Due to poor quality, we do not accept files from Researchgate

Submitted PDF Full Texts will always be free for everyone
(We only charge for PDFs that we need to acquire)

Select a PDF file:

Other references

Porchet, M.; Andries, J.C.; Dhainaut, A., 1986: Advances in invertebrate reproduction. 4. Proceedings of the Fourth International Symposium of the Society of Invertebrate Reproduction (ISIR) held in Villeneuve-d'Ascq, France, from 1-5 September 1986. The many contributions in these proceedings are arranged under the headings gametogenesis and internal control (about 30 papers, mainly on endocrine control of reproduction in invertebrates, including arthropods, platyhelminths, annelids and trema...

Schaller, G., B.; Aili, K.; Tashi-Dorjie, H.; Ping, C., 2007: A winter wildlife survey in the northern Qiangtang of Tibet Autonomous Region and Qinghai Province, China. We surveyed wildlife along a 1692 km transect of uninhabited terrain in the northern Qiangtang Nature Reserve of Tibetan Autonomous Region (TAR) and the Kekexili Nature Reserve of Qinghai from 1 -23 November, 2006. The Tibetan antelope (chiru) (Pa...

Brussee, J.M.; Yeo, T.W.; Lampah, D.A.; Anstey, N.M.; Duffull, S.B., 2016: Pharmacokinetic-Pharmacodynamic Model for the Effect of l-Arginine on Endothelial Function in Patients with Moderately Severe Falciparum Malaria. Impaired organ perfusion in severe falciparum malaria arises from microvascular sequestration of parasitized cells and endothelial dysfunction. Endothelial dysfunction in malaria is secondary to impaired nitric oxide (NO) bioavailability, in part...

Choudhari B.K.; Chakrawar V.R., 1982: Effect of seed treatment using some chemicals on the shoot and root growth of rangpur lime citrus limonia. The effect of seed treatment of Rangpur lime with GA, NAA [naphthalene acetic acid], thiourea ad KNO3 on the growth of seedling was undertaken during 1977-1978. There was significant increase in height of seedling, stem diameter, number of leaves...

Ishiwatari R.; Yamamoto S.; Machihara T., 1989: Molecular composition and diagenesis of organic matter (geolipids) in sediments from site 677 and 678, Leg 111. Proceedings of the Ocean Drilling Program, Scientific Results 111: 227-230

Grad R.M., 1984: Human experimental and informed consent. Canadian Medical Association Journal 131(8): 932, 935

Vrajová, M.; Peková, Sňa.; Horácek, Jí.; Höschl, C., 2011: The effects of siRNA-mediated RGS4 gene silencing on the whole genome transcription profile: implications for schizophrenia. The regulator of G-protein signaling (RGS) molecules represent a class of proteins that modulate the signaling activity of G-protein coupled receptors. Regulator of G-protein signaling 4 (RGS4) is of particular interest in schizophrenia due to rep...

ISHIYAMA.S.; SAKABE.T.; USHIO.S.; KISHIOKA.M.; FURUHASHI.M.; JONO.S.; TAKAHASHI.U.; NAGASAKI.Y.; KAWAKAMI.I.; NISHIOKA.S.; NAKAYAMA.I., 1965: Body Fluid Concentrations And The Clinical Effect Of Lincomycin, A New Antibiotic. Journal of Antibiotics. Ser. B 18: 120-125

Pipinov, A.V.; Orduian, G.S.; Fanardzhian, V.V., 1968: Input of the temporal characteristics of neuronal activity into a universal digital computer. Zhurnal Vysshei Nervnoi Deiatelnosti Imeni i P Pavlova 18(4): 739-744

Dragoescu, E., 1986: Methods of measuring leaf area in crops. The following methods of measuring crop leaf area are described: the use of graph paper; planimetry; leaf length and breadth measurements; weighing; and photometry.