bluuebunny/crossref_metadata_2025_split huggingface dataset:
Change in intracellular distribution of cAMP‐binding capacity in sea urchin embryos during early development
Authors: Fujino Yukio , Yasumasu Ikuo 
Published: February 2005

AbstractIn the sea urchin, Strongylocentrotus intermedius, cAMP‐binding capacity was found in the sedimentable fractions obtained by centrifuging the homogenate of the embryos at 10,000g for 20 min and 105,000g for 1 h, and also the supernatant fraction by centrifugation at 105,000g. The cAMP‐binding capacity was estimated depending on the radioactivity of 3H‐cAMP found in the nonfiltered matter obtained by a filtration through a Millipore filter of a mixture containing 3H‐cAMP and each fraction. Prior to the filtration, the mixture was incubated at 0°C for 1 hr. In all fractions, the addition of nonlabeled cAMP to the mixture containing 3H‐cAMP resulted in a marked decrease in the radioactivity in the nonfiltered matter. cGMP, cTMP, and cUMP caused only a slight decrease in the radioactivity in the nonfiltered matter. These indicate that specific cAMP binding occurs in the nonfiltered matter of all fractions. The extent of decrease in 3H‐radioactivity by cIMP was higher than that caused by cAMP in the 10,000g sedimentable fraction, but in the other fractions, it was as low as observed when cGMP, cTMP, and cUMP were added. This suggests that the nature of cAMP‐binding matter in this fraction differs somewhat from those in the other fractions. cAMP‐binding capacity in this fraction (10,000g sedimentable fraction) increased gradually during development and the capacity in the other fractions, especially in the supernatant fraction, decreased at the gastrula stage. Protein kinase activity was also found in these fractions. Alteration of intracellular distribution of cAMP‐binding proteins and protein kinases during development probably shows the change in the role of protein kinase in the mechanism of development.
Novel procedures for collection of sea urchin egg cortical granule exudate: Partial characterization and evidence for postsecretion processing
Authors: Baginski Richard M. , McBlaine Paul J. , Carroll Edward J. 
Published: February 2005

AbstractWe have developed two procedures to collect total cortical granule exudate in a soluble form from eggs of the sea urchin Strongylocentrotus purpuratus. Egg suspensions were either treated with dithiothreitol to disrupt the vitelline envelope or divalent cations were removed postinsemination to prevent the normal vitelline‐to‐fertilization envelope transition. Rapid acidification of the insemination mixture (dithiothreitol‐treated eggs) to pH 6.0 prevented precipitation of the paracrystalline protein fraction described by Bryan [1970a]. Exudate was partitioned into three fractions. The pH 8.0‐insoluble fraction appeared to be identical to the paracrystalline protein fraction. The pH 8.0‐soluble fraction was separated into pH 4.0‐soluble and‐insoluble fractions. Analysis for peroxidase and protease activities showed that peroxidase activity was localized in all three fractions whereas protease activity was restricted to the pH 4.0 insoluble fraction as reported [Carroll and Epel, 1975]. A minimum of six major proteins were detected on native polyacrylamide gels of total exudate. Under reducing and denaturing conditions, 12 polypeptides ranging from 19,000 to 165,000 in molecular weight were detected in total exudate; six polypeptides were recovered in the pH 8.0‐insoluble fraction. To test the hypothesis that protease and peroxidase activities process cortical granule proteins after secretion, we inseminated eggs in solutions containing peroxidase and protease inhibitors. The paracrystalline protein fraction crystallized slowly from insemination mixtures containing both inhibitors compared to controls and there were dramatic differences in exudate electrophoretic patterns. We suggest that cortical granule protease and peroxidase activities process the exudate so that the paracrystalline protein fraction rapidly crystallizes during normal fertilization.
Hyperactivated motility patterns of ram spermatozoa recovered from the oviducts of mated ewes
Authors: Cummins J. M. 
Published: February 2005

AbstractThe contents of the oviducts of ewes were recovered by flushing with small volumes of culture medium, 22½–24¼ hr after mating. The ampulla was flushed separately from the uterotubal junction and isthmus. Among the motile spermatozoa recovered, a proportion exhibited “hyperactivated” motility, also known as “activated”, or “whiplash” motility. This was characterized by increased flexion of the neck, increased amplitude of the flagellar waves, and marked asymmetry of beat. Two types of hyperactivation appeared: in the first, spermatozoa swam in a repetitive, nonprogressive circling pattern and appeared to have intact acrosome caps; in the second, the spermatozoa showed a propensity to stick to glass by the equatorial segment and most had modified or missing acrosome caps. The proportions of motile spermatozoa exhibiting hyperactivation were greatest in the ampullae, as were the proportions with modified or absent acrosomes. Hyperactivation is a capacitation‐associated phenomenon that has now been reported for one or more species from seven orders of eutherian mammals. It may well be a universal aspect of the prefertilization behavior of mammalian spermatozoa and is probably of advantage to the fertilizing spermatozoon within the oviduct.
Activities of X‐linked enzymes in spermatocytes of mice rendered sterile by chromosomal alterations
Authors: Hotta Y. , Chandley A. C. 
Published: February 2005

AbstractSpermatocytes in the late prophase of first meiotic division isolated from sterile males retain higher activities for three X‐linked enzyme5, phosphoglycerate kinase (PGK)‐1, glucose‐6‐phosphate dehydrogenase (G6PD), and hypoxanthine‐guanine phosphoribosyl transferase (HGPRT) than those of fertile males. The sterilty of the male is presumed to be owing to the rearrangement of X‐chromosome material and the possibility of abnormal meiotic X‐chromosome inactivation is discussed.
Effect of antibody to detergent solubilized zonae pellucidae on in vivo and in vitro fertilization in the mouse
Authors: Tsunoda Y. , Sugie T. 
Published: February 2005

AbstractAn antiserum was produced in one rabbit against mouse zonae pellucidae solubilized with 70 mM Na2SO3, 1% SDS, and 0.04 mM CuSO4. An IgG of zona antibody completely inhibited fertilization both in vitro and in vivo in the mouse. F(ab′)2 fragment obtained by pepsin digestion of IgG zona antibody inhibited fertilizability of eggs in vitro but did not inhibit fertilization in vivo after passive immunization.
Calcium and adenosine affect human sperm adenylate cyclase activity
Authors: Hyne Ross V. , Lopata Alex 
Published: February 2005

AbstractThe adenylate cyclase activity of human ejaculated spermatozoa in broken‐cell preparations was investigated. In the presence of 5 mM metal cations and 0.1 mM ATP, the relative enzyme activity with Mn2+, Ca2+, Mg2+, Ba2+ was 1.00, 0.28, 0.22, and 0.03, respectively. Added Ca2+ appeared to activate the enzyme in the presence of Mn2+ or Mg2+. The human sperm adenylate cyclase was stimulated by ∼ 2‐fold by free Ca2+ (lmM) in the presence of Mg2+ (5 mM). If the GTP analogue, 5′‐guanylyl imidophosphate (Gpp(NH)p) was added to the sperm homogenate in the presence of 200 μM ethylene‐glycol‐bis (β‐aminoethylether) N,N′‐tetraacetic acid (EGTA), the adenylate cyclase activity was increased by approximately 25%, but with the addition of 280 μM Ca2+ there was a decrease in enzyme activity. A similar response to low concentrations of Ca2+ was obtained after complementation of the sperm enzyme with the guanine nucleotide regulatory component from human erythrocytes, where the addition of 40 μM Gpp(NH)p, 200 μM EGTA, and Ca2+ (≤ 160 μM) stimulated the sperm enzyme ∼ 3–4‐fold, but the further addition of Ca2+ (280 μM, final) neutralized the stimulatory effect. The addition of adenosine, and the nucleotides 5′‐AMP and 5′‐ADP inhibited the enzyme, whereas guanine and 5′‐GMP had no appreciable effect. Human follicular fluid and serum also had little direct effect on the sperm adenylate cyclase. These resuls suggest that Ca2+ might be an important physiological modulator of the human sperm adenylate cyclase.
Sperm motility in the horseshoe crab. III. Isolation and characterization of a sperm motility initiating peptide
Authors: Clapper David L. , Epel David 
Published: February 2005

AbstractSperm motility in Limulus is initiated by a sperm motility initiating factor (SMI) that emanates from Limulus eggs. This report describes the partial purification of SMI (greater than 230‐fold purification with respect to protein content) with 40% recovery. SMI appears to be a hydrophobic peptide of 500–2,000 MW. Although probably not purified to homogeneity, SMI is estimated to be active at a concentration of less than 0.2 μM.
Effect of an extract of nereis virens on mammalian spermatozoa
Authors: Gordon Mildred , Morris Eugene G. , Stark Freddy , Williams William L. , Young Ron J. 
Published: February 2005

AbstractEpididymal sperm of the mouse, rat, and guinea pig and ejaculated sperm of rabbits are cleaved at the head‐tail junction by an extract of Nereis virens. Annelids are extracted with water and the extract is purified by ion exchange chromatography. Electron microscopy shows that the extract acts on the filaments connecting the capitulum of the tail with the basal plate lining the nuclear envelope. Following detachment, the basal plate remains with the head. The extract contains proteases as indicated by hydrolysis of tosyl arginine methyl ester (TAME), benzoyl arginine ethyl ester (BAEE), and Azocoll, a general protease substrate. The hydrolysis of TAME is inhibited by tosyl lysine chloromethyl ketone (TLCK), a trypsin inhibitor, but TLCK does not prevent head‐tail separation by the Nereis extract. Similarly tosyl phenylalanine chloromethyl ketone (TPCK), a chymotrypsin inhibitor, and phosphoramidon and leucyltryptophan, both thermolysin and acrolysin inhibitors — singly or in combination — do not prevent hydrolysis of Azocoll. Head‐tail separation activity of the extract was inhibited by dithiothreitol, which reduces disulfide bonds, and phenylmethyl sulfonyl fluoride, an inhibitor of serine proteases. These results indicate that the extract is a mixture of proteases, one being a serine protease similar to trypsin.Digestion of the connecting filaments with the pure proteases, trypsin and Staphylococcus aureus V8 protease, has yielded the following information on the proteins of the filaments. The accessibility of arginine and/or lysine peptide bonds to enzyme action is highest in rat sperm filaments, whereas those in the filaments of mouse, rabbit, and guinea pig sperm are less accessible than in the rat. Another possibility is that the total content of arginine and/or lysine varies between the species. The most dramatic difference is the enzymatic action on glutamyl peptide bonds of the filaments, the order being: mouse 〉 rat 〉 rabbit, with guinea pig sperm filaments completely resistant over the time course of the experiment.
Stabilization in vivo and in vitro of the spermatozoon head and tail to detachment induced by primary amine, thiol, and detergent
Authors: Young R. J. , Cooper G. W. 
Published: February 2005

AbstractRabbit spermatozoa recovered from the reproductive tract of females 12–13 hr postcoitum resisted head/tail separation induced by n‐butylamine and dithiothreitol, but not sodium dodecylsulfate. Stabilization of the sperm head/tail junction also developed in vitro at 37°C in physiological media and in saline‐Tris‐HCl (pH 7.4). Resistance to dithiothreitol occurred in motile, but not immotile spermatozoa. Only nonmotile spermatozoa developed resistance to sodium dodecylsulfate in vitro, whereas both motile and immotile spermatozoa became resistant to n‐butylamine. Stabilization to n‐butylamine was time and temperature dependent and was accelerated by Cu2+, Mg2+, and Zn2+, but not Mn2+. The resistance of hamster and rabbit spermatozoa to n‐butylamine developed in physiological media over the same time intervals as required for capacitation and the acquisition of hyperactivated motility.Reagents that react with sulfhydryl groups had no effect on the development of resistance to n‐butylamine but inhibited stabilization to sodium dodecylsulfate, suggesting that the latter stabilization may result from the formation of disulfide crosslinks at the head/tail junction. Reduction of aldehyde groups by sodium cyanoborohydride did not prevent stabilization to sodium dodecylsulfate, but did reduce detachment by dithiothreitol. Aldehyde groups thus are not involved in the stabilization of the head/tail junction to sodium dodecylsulfate, but may participate in new crosslinks stabilizing the head/tail junction to dithiothreitol. Inhibitors of transglutaminase did not prevent development of resistance to n‐butylamine, sodium dodecylsulfate, or dithiothreitol indicating that head/tail stabilization does not involve intermolecular γ‐glutamyl‐ϵ‐dysine bonds.
Temporal synthesis of mitochondrial proteins from mouse epididymal spermatozoa
Authors: Hecht Norman B. , Kennington Ellzabeth 
Published: February 2005

AbstractMitochondria from ejaculated bovine spermatozoa contain a group of polypeptides ranging in molecular weights from 13,000 to 35,000 not found in other bovine or murine testicular mitochondria [Hecht and Bradley, 1981]. These proteins are present in the mitochondria isolated from both epididymal and ejaculated spermatozoa. To establish when during epididymal transport, spermiogenesis, and/or meiosis these proteins are synthesized, the synthesis intervals for the mitochondrial proteins from cauda epididymal spermatozoa were established following intratesticular injection of (35S)methionine. Mice were killed every third day over a 33‐day period and cauda epididymal spermatozoa were fractionated into mitochondrial and head components. Radioactivity in each fraction was monitored by liquid scintillation counting. Maximal incorporation was observed during spermiogenesis, although substantial amounts of protein were synthesized during meiosis. Analysis of the mitochondrial polypeptides by gel electrophoresis revealed that many polypeptides such as the cysteine‐rich structural protein of the mitochondrial capsule were synthesized over prolonged intervals of spermiogenesis and meiosis rather than in a brief specific time period. These results suggest that spermatozoal mitochondria are produced by a sequential substitution of new proteins into the differentiating mitochondria rather than the abrupt appearance of a new class of mitochondria during spermatogenesis.
Active immunization of cynomolgus monkeys (Macaca fascicularis) with porcine zonae pellucidae
Authors: Gulyas Bela J. , Gwatkin Ralph B. L. , Yuan Lydia C. 
Published: February 2005

AbstractCynomolgus monkeys (Macaca fascicularis) were immunized with porcine zonae pellucidae to assess the possible antifertility effects of the zona antibodies. Serum antibody titers were evaluated utilizing a rapid solid‐phase radioimmunoassay. Six of twelve monkeys conceived 6 to 10 wk after vaccination. All monkeys reached maximal antiserum titers by the time of conception, although the six animals that did not conceive had considerably lower antibody titers. Further pregnancies did not occur until antibody level had declined markedly, 8 mo after last immunization. The menses of all but one of the remaining six monkeys were interrupted intermittently. Also, the usual midcycle elevated estradiol levels were absent for several cycles. Both menses and midcycle estradiol peaks were reestablished in all but one monkey 3 to 5 mo after the last booster was given. Two monkeys conceived when serum antibody levels dropped to one fourth of maximal, but both had a still birth. Histological observations showed accumulation of luteal tissue and massive atresia of small follicles at the end of the study (18 mo). We conclude that through heteroimmunization with porcine zona pellucida monkeys can become infertile and that this condition is reversible. Because the zona preparation used in this study appeared to contain traces of nonzona material, it was not possible to determine whether the menstrual irregularities and oocyte atresia that we observed were owing to immunological effects on the zona itself or to the production of antibodies against other ovarian components.
Effects of egg aging on in vitro fertilization and first cleavage division in the hamster
Authors: Juetten Jacquline , Bavister Barry D. 
Published: February 2005

AbstractThe postovulatory fertile life of mammalian eggs is remarkably short (approximately 6‐36h). Anomalies of embryogenesis may result from fertilization of aged, defective eggs. Attempts to study this problem using whole‐animal models are complicated by chances in the natural milieu of the gametes. In the present study, postovulatory hamster eggs were allowed to agein vivo then fertilized in vitro. Cumulus‐intact eggs recovered from superovulated hamsters either 2 or 9 h after the estiated time of ovulation (12 h postHCG) were incubated for 4 h with preincubated sperm suspentions in a modified Tyrode's solution devised for in vitro fertilization. Eggs were either fixed or cultured for another 20h in fresh medium to allow cleavage to occur, then examined by light microscopy (phase and interference‐contrast). No significant difference was found in the ablities of fresh and aged eggs to be penetrated by spermatozoa (94% vs 90%, respectively; 8 replicated experiments), but only 59% of penetrated aged eggs were found to undergo morphologically normally fertilization (2 polar bodies, 2 prounclei) compared with 75% of fresh eggs (difference significant, P< 0.01). About 13% of eggs were polyspermic in both categories. The most common anomaly in aged fertilied egges was failure to extrude the second polor body (23% off eggs vs 8% of fresh eggs, P < 0.01). Only 21% of aged eggs underwent first cleavaage, and only 74% of these appeared morphologically normal, compared with value of 68% and 98%, respectively, for fresh eggs. These data show that in the hamster, abnormal fertilization and cleavage failure can, in part, be directly attributed to postovulatory deterioration of eggs. We also infer that the apparently very short penetrable life of hamster eggs in vivo shown by previous investigators is an indirect effect of postovulatory changes in the female reproductive tract that are unfavorable for sperm‐egg interactions.
A species‐specific sperm factor dispersing the jelly coat of the egg of the sea urchin, Anthocidaris crassispina
Authors: Yamada Yuji , Aketa Kenji 
Published: February 2005

AbstractA species‐specific factor capable of disersing the jelly coat surrounding eggs has been purified from sperm of the sea urchin, Anthocidaris crassisina. It does not exert its effect on the vitelline layer. The purification has been accomlished by a four‐step procedure involving ammonium sulfate fractionation, gel filtration on Sepharose CL‐4B, ion‐exchange column chromatography on DEAE‐cellulose, and affinity column chromatograhy on heparin‐Seharose CL‐6B. The isolated factor is homogenous in sodium dodecyl sulfate polyacrylamide gel electrohoresis in the presence or absence of β‐mercatoethanol, estimated molecular weight being about 140,000.The jelly dispersion by the present factor is activated by CaCl2, and inhibited by KCl, MnCl2, EDTA, and EGTA, and by sulfated saccharides such as chondroitin sulfate A and C, heparin, and glucose‐6‐sulfate, Inorganic sulfated such as (NH4)2SO4 and Na2SO4 have no effect on jelly dispersion. This factor is heat‐labile, its activity in 30 min at 50°C.The present factor is found also in the seminal Plasma, and released from sperm themselves by treatment with Triton X‐100 .These results suggest that this factor is loosely bound to the serm surface. Although glycosidase and arylsulfatase activities are detectable in the seminal plasma, these enzyme activities are not detectable in the purified jelly disersing factor.Only trypsin and α chymotrysin among commercial enzymes tested dispersing activity is inhibited neither by trypsin inhibitors such as N‐α‐p‐tosyl‐L‐lysine‐chloromethyl ketone, soybean trypsin inhibitor, ovomucoid trypsin inhibitor, nor by chymotrypsin inhibitors such as L‐1‐tosylamide‐2 pheny‐ethylcholoromethyl ketone and chymostatin Participation of trysin‐like and chymotrypsin‐like enzymes in jelly dispersion seems unlikely.
Ultrastructure of a crystalline inclusion in the cytoplasmic droplet of bovine spermatozoa
Authors: Olson G. E. , Winfrey V. P. , Noland T. D. , Garbers D. L. 
Published: February 2005

AbstractAn elongate crystalloid inclusion has been noted in the cytoplasmic droplet of cauda epididymal bovine spermatozoa. The crystalloid appears to be composed of an aggregate of parallel 10 nm diameter filamentous elements that are associated laterally with one another. It has a regular cross‐banding pattern that repeats at 13–15‐nm intervals. A purified fraction of detached droplets was prepared by centrifugation of sperm suspensions onto Percoll gradients. The detached droplets also exhibited the crystalline inclusion. The origin and possible functions of this structure are discussed.
On the role of glucose in capacitation and acrosomal reaction of guinea pig sperm
Authors: Mújica A. , Ruíz M. A. Valdes 
Published: February 2005

AbstractIn order to determine whether metabolizable sugars delayed capacitation of guinea pig spermatozoa, these cells were pre‐incubated in Tyrode's pyruvate lactate glucose medium (T‐PLG) or Tyrode's glucose solution (T‐G). They were then transferred to minimal culture medium containing pyruvate and lactate (MCM‐PL) and the occurrence of acrosomal reactions (AR) was determined by light microscopic observations of wet mount aliquots. The percentage of acrosomal reactions was quantitated in fixed samples and occurrence of a true AR was confirmed by electron microscopy. Activated acrosome‐reacted spermatozoa were observed within 5 min when cells were transferred to MCM‐PL solution, after preincubating them for 60–120 min either in T‐PLG or T‐G media. By 15 min in MCM‐PL the percentage of acrosome‐reacted spermatozoa reached values similar to those obtained in cells pre‐incubated from the beginning in MCM‐PL medium (P > 0.05 in both) but significantly different from T‐PLG and T‐G controls (P < 0.0005 in both). The acrosomal reaction was external calcium dependent and independent of the Tyrode's media pH ranging from 7.2 to 8.0. The results obtained suggested that capacitation occurred in T‐PLG and that it was not delayed by glucose; the results also suggested that capacitation could occur within a short time with glucose as the only exogenous substrate, but that the acrosome reaction could have been arrested by a glucose metabolite. Data are presented which suggest that intracellular levels of glucose‐6‐phosphate (as 2‐deoxyglucose‐6‐phosphate)could play a key role in the expression of the acrosome reaction in sperm already able to perform it. A new hypothesis is suggested for the development of the fertilizing potential of guinea pig sperm when in the female genital tract.
Evaluation of early embryonic mortality in donor insemination by a mathematical model, globally and depending on semen quality
Authors: Schwartz D. , Heuchel V. , Mayaux M. J. , O'Quigley J. 
Published: February 2005

AbstractStating the probability of pregnancy per cycle as PoPFPv, the product of the probabilities of ovulation, fertilization, and egg viability, the model allows an estimate of PF and PoPv for a series of cycles with known insemination timing. Such results obtained from a series of donor insemination (AID) compared with those generally admitted in natural reproduction suggest that the lower pregnancy rate in AID (all the lower when the postthaw motility is low) is owing to a lower egg viability. Since the abortion rate does not seem higher, there might be a sizable rate of very early embryonic deaths in AID perhaps even as early as nondeveloping eggs.