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1.
J Chromatogr B Biomed Sci Appl ; 746(2): 141-50, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11076066

RESUMO

These studies showed that the fractionation of bovine seminal plasma based on lectin agarose affinity chromatography, employing lectins specific to asparagine linked oligosaccharides, and a lectin specific for fucosylated glycans, lead to products with an inhibitory effect on the acrosine-like protease activity. This effect decreases when glycocompounds containing fucosylated Lewis(x) structures are removed, suggesting that these compounds might have some role in the modulation of this activity in the bull. In the fraction devoid of high mannose, hybrid and non-bisecting lactosaminic oligosaccharide-containing glycocompounds, PDC-109 and aSFP proteins were detected and characterized at microscale.


Assuntos
Cromatografia de Afinidade/métodos , Endopeptidases/metabolismo , Inibidores de Proteases/farmacologia , Proteínas/análise , Proteínas/química , Sêmen/química , Sequência de Aminoácidos , Animais , Bovinos , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Endopeptidases/química , Lectinas/química , Masculino , Inibidores de Proteases/química , Proteínas de Plasma Seminal
2.
Cell Biol Toxicol ; 16(2): 77-82, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10917562

RESUMO

The acrosome, a complex organelle, plays a key regulatory role in the sperm-egg interaction. We have previously shown that ascorbic acid affects both motility and spectrin protein patterns in sperm. In this study, we further characterized the changes in spectrin in sperm challenged with ascorbic acid, using SDS-PAGE, western blots, and immunofluorescence. Ascorbic acid shifts spectrin to a higher-molecular-weight species based on western blot studies. This shift in the spectrin band correlates with a striking series of changes in spectrin immunofluorescence patterns. Upon ascorbic acid challenge, spectrin localization changes, eventually resulting in the formation of vesicles. These vesicles can reach sizes up to five times the original volume of the sperm cell and sometimes show multiple spikes. These findings indicate that a novel process is taking place in the acrosome upon ascorbic acid challenge and suggest that the cytoskeleton may be a useful target for studying and hopefully controlling the sperm-egg interaction.


Assuntos
Acrossomo/metabolismo , Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Espectrina/metabolismo , Acrossomo/efeitos dos fármacos , Animais , Bovinos , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Eletroforese em Gel de Poliacrilamida , Imunofluorescência , Masculino , Espectrina/análise
3.
Zygote ; 1(4): 309-13, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8081828

RESUMO

Intraperitoneal injections of extracts of Spartium junceum in adult male rats were shown to reduce the rate of fertility and acrosin enzyme activity. For the latter the drug effects could be divided into two phases: in the first stage a significant increase in proteolytic activity was observed in all experimental animals examined; and in the second stage, there was a general decrease of up to 50% in enzyme hydrolytic properties. There is a notable difficulty in correlating the acrosin activity and the data obtained from mating tests. The effect of drugs on the activity of another acrosomal protease, benzamidine-resistant protease, was assayed. A significant decrease in this enzyme was noted though the modality was different from that of acrosin. Extrapolating the data of the two co-extracted acrosomal proteases, the ratio of acrosin-like protease [E] and benzamidine-resistant protease [E]x, it was possible to correlate the value expressed to the rate of pregnancy. The implications of this finding is discussed although the exact molecular basis of the phenomenon is uncertain.


Assuntos
Acrosina/metabolismo , Fertilidade/efeitos dos fármacos , Extratos Vegetais/farmacologia , Acrosina/antagonistas & inibidores , Animais , Anticoncepcionais Masculinos/farmacologia , Estabilidade Enzimática , Feminino , Fertilidade/fisiologia , Cinética , Masculino , Gravidez , Ratos , Espermatozoides/efeitos dos fármacos , Espermatozoides/enzimologia
4.
Zygote ; 1(1): 71-8, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8081803

RESUMO

Male adult rabbits and rats treated with Spartium junceum showed a significant decrease in fertility, demonstrated by a lower number of pregnancies. The target of the drug seems to be the acrosomal protease system, the activity of which appears greatly reduced, while the morphology of testicular cells and epididymal spermatozoa is only partially affected. The antifertility effect is completely reversible.


Assuntos
Anticoncepcionais Masculinos/farmacologia , Fertilidade/efeitos dos fármacos , Extratos Vegetais/farmacologia , Acrossomo/efeitos dos fármacos , Acrossomo/enzimologia , Acrossomo/ultraestrutura , Animais , Anticoncepcionais Masculinos/isolamento & purificação , Anticoncepcionais Masculinos/toxicidade , Epididimo/efeitos dos fármacos , Epididimo/ultraestrutura , Feminino , Masculino , Microscopia Eletrônica , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Gravidez , Inibidores de Proteases/isolamento & purificação , Inibidores de Proteases/farmacologia , Inibidores de Proteases/toxicidade , Coelhos , Ratos , Ratos Wistar , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/ultraestrutura
5.
Enzyme ; 34(1): 39-44, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3910424

RESUMO

The anticlotting properties of the fungal protease EL 25-79 have been assayed using freshly collected human and bovine blood and sodium-citrate-treated samples. 0.1% EL 25-79 was sufficient to prevent clotting. At this concentration, the protease provokes only a limited proteolysis of major plasma proteins, and at the same time does not digest the hemoglobin contained in the erythrocyte, because it is protected by the cell membrane. The kinetic studies on the enzyme action were performed using both fibrinogen and albumin. The data show that the ratio between the initial velocity of hydrolysis of human fibrinogen and human albumin at enzyme concentrations close to zero is 85. The SDS PAGE analyses of the protein patterns of the corresponding samples for the kinetic study confirmed these data.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Peptídeo Hidrolases/farmacologia , Animais , Eletroforese das Proteínas Sanguíneas , Bovinos , Fibrinogênio/metabolismo , Hemoglobinas/metabolismo , Humanos , Técnicas In Vitro , Cinética , Peso Molecular , Peptídeo Hidrolases/metabolismo , Peptídeos/sangue , Albumina Sérica/metabolismo
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