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1.
Cancer Res ; 48(8): 2174-8, 1988 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-2964898

RESUMO

This study evaluates the effect on spermatogenesis of coadministration of Cytoxan (cyclophosphamide) and nafarelin, a luteinizing hormone-releasing hormone agonist. Nafarelin causes complete aspermatogenesis in dogs by interrupting the hypothalamic-pituitary-gonadal axis, which might protect against the testicular cytotoxicity associated with cyclophosphamide. The four treatment groups, each consisting of 2 mature male beagle dogs, were (a) no drug; (b) cyclophosphamide (p.o. 3x weekly for 43 and 48 wk for a total dose of 582 and 709 mg/kg, with dose varying according to weekly hematological profile); (c) nafarelin (2 micrograms/kg s.c. daily for 48 and 52 wk); and (d) cyclophosphamide plus nafarelin [same schedule as above with cyclophosphamide (570 and 698 mg/kg total dose) starting 7 wk after beginning nafarelin]. Plasma testosterone, spermatogenesis, and ejaculate volume were completely suppressed by nafarelin prior to starting cyclophosphamide. By 2 wk after cessation of treatment (posttreatment, PT), plasma testosterone reached normal levels, and at 5 wk PT ejaculates appeared which reached normal volumes 2 to 3 wk later. Normally motile ejaculated spermatozoa were noted at 6 to 8 wk PT in nafarelin-only-treated animals; normal sperm numbers were reached at 14 wk PT. The animals receiving cyclophosphamide plus nafarelin were azoospermic for the entire 65-wk PT period, and at 65 wk PT no germinal cells were found upon evaluation of testicular histology. Sperm numbers in cyclophosphamide-only-treated animals began to rise 10-11 wk PT and reached 150 x 10(6) sperm/ejaculate at approximately 65 wk PT (contemporaneous control dogs had sperm numbers of approximately 300-600 x 10(6)/ejaculate). Spermatogenesis in these cyclophosphamide-only-treated animals was normal in most seminiferous tubules at this time. The addition of nafarelin to cyclophosphamide treatment thus exacerbated the deleterious effects of cyclophosphamide on the testes, suggesting caution for use of such a protocol clinically.


Assuntos
Ciclofosfamida/toxicidade , Hormônio Liberador de Gonadotropina/análogos & derivados , Testículo/efeitos dos fármacos , Animais , Células Sanguíneas/efeitos dos fármacos , Cães , Sinergismo Farmacológico , Hormônio Liberador de Gonadotropina/farmacologia , Masculino , Nafarelina , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/patologia , Testosterona/sangue
2.
Neurology ; 47(5): 1329-31, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8909453

RESUMO

We examined the toxicity of both single and multiple subcutaneous injections of recombinant human ciliary neurotrophic factor (rhCNTF) in 72 patients with ALS, in doses ranging from 2 to 100 micrograms/kg. Adverse events were generally dose related and ranged from mild to severe. The tolerability of daily subcutaneous rhCNTF was equivalent to placebo at doses < or = 5 micrograms/kg/day. At higher doses, anorexia, weight loss, reactivation of herpes simplex virus (HSV1) labialis/stomatitis, cough, and increased oral secretions occurred.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Fatores de Crescimento Neural/efeitos adversos , Proteínas do Tecido Nervoso/efeitos adversos , Adulto , Fator Neurotrófico Ciliar , Tolerância a Medicamentos , Feminino , Humanos , Masculino , Método Simples-Cego
3.
Neurology ; 50(3): 768-72, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9521272

RESUMO

We modified the World Federation of Neurology (WFN) diagnostic criteria for ALS to facilitate early diagnosis and used these criteria for enrollment of ALS patients in a clinical trial. The criteria developed required lower motor neuron (LMN) involvement in at least two limbs and upper motor neuron involvement in at least one region (bulbar, cervical, or lumbosacral). The EMG finding of fibrillation potentials was required for evidence of LMN involvement. Electrodiagnostic studies, neuroimaging, and laboratory studies were also used to exclude disorders that might mimic ALS. Using these criteria, the diagnosis of ALS was made at a mean time of 9.7 months from onset of symptoms, which compares favorably with the 12-month period cited in the literature. Using clinical assessment at completion of the trial, the diagnosis of ALS was believed to be accurate in those patients entered in the trial. However, pathologic confirmation of the diagnosis of ALS was not obtained. Based on our preliminary experience, we propose that these ALS diagnostic criteria will facilitate early diagnosis of ALS. Future studies should prospectively compare these criteria with the WFN criteria currently in use.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Cooperação Internacional , Neurologia/métodos , Esclerose Lateral Amiotrófica/tratamento farmacológico , Fator Neurotrófico Ciliar , Ensaios Clínicos como Assunto , Humanos , Proteínas do Tecido Nervoso/uso terapêutico , Guias de Prática Clínica como Assunto , Proteínas Recombinantes , Fatores de Tempo
4.
J Med Chem ; 35(21): 3942-8, 1992 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-1279174

RESUMO

The incorporation of Arg residues into position 6 of gonadotropin releasing hormone antagonists had resulted in compounds with increased in vivo potency but also made these analogues potent mast cell degranulators. We have focused on the substitution of position 8 by hArg(R)2 (NG,NG'-dialkylhomoarginine) substitutions, based on the hypotheses that the Arg-Pro sequence is of major importance for this side effect and that shielding of the charge may be an effective way to block degranulation. Analogues in four series were evaluated: (A) [N-Ac-D-Nal(2)1,D-pCl-Phe2,D-Pal-(3)3,6,Arg5,hArg(R)2(8),D-+ ++Ala10]GnRH, (B) [N-Ac-D-Nal(2)1,D-pCl-Phe2,D-Pal(3)3,6,hArg(R)2(5,8),D-Ala10 ]-GnRH, (C) [N-Ac-D-Nal(2)1,D-pCl-Phe2,D-Pal(3)3,6,hArg(R)2(8),D-Ala10]G nRH, (D) [N-Ac-D-Nal(2)1,D-pCl-Phe2,D-Pal(3)3,D-hArg(R)2(6),hArg(R)2( 8),D-Ala10]GnRH. Although substitution by hArg(Et)2, hArg(Bu), hArg(CH2)3, and hArg(CH2CF3)2 was tested, in each series the hArg(Et)2 residue was superior. Two compounds were considered for clinical evaluation: [N-Ac-D-Nal(2)1,D-pCl-Phe2,D-Pal(3)3,6,hArg(Et)2(8),D-Ala10] GnRH and [N-Ac-D-Nal(2)1,D-pCl-Phe2,D-Pal(3)3,D-hArg(Et)2(6),hArg(Et) 2(8),D- Ala10]GnRH (ganirelix acetate). These compounds had high potency for ovulation suppression and low histamine-releasing potency in vitro (ED50 = 0.6, 0.29 microgram/rat and EC50 = 196, 13 micrograms/mL, respectively). Ganirelix is currently in Phase II clinical trials and appears to be the most potent GnRH antagonist tested in humans (based upon ED50 for 24-h suppression of testosterone levels).


Assuntos
Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Liberação de Histamina/efeitos dos fármacos , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Feminino , Hormônio Liberador de Gonadotropina/análogos & derivados , Masculino , Dados de Sequência Molecular , Ovulação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
5.
Fertil Steril ; 51(1): 190-3, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2910712

RESUMO

In the present study of 50 patients, it was determined that those with seminal deficiencies in masturbated samples showed greater improvement in semen parameters with I-SCD use than the nondeficient groups with which they were compared. The use of I-SCD in oligospermia and OTA Syndrome is therefore indicated, both diagnostically and therapeutically. The subjective rating of sexual stimulation elicited when I-SCD was used was far superior than with masturbation. It is believed the success of I-SCD is due, in part, to this greater degree of sexual stimulation, presumably by added loading of the vas deferens prior to ejaculation.


Assuntos
Coito , Masturbação , Sêmen/fisiologia , Manejo de Espécimes/instrumentação , Humanos , Infertilidade Masculina/fisiopatologia , Masculino , Manejo de Espécimes/métodos , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/anatomia & histologia
6.
Fertil Steril ; 41(3): 455-9, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6698237

RESUMO

The effect of precoital vaginal placement of three spermicidal formulations on postcoitally recovered vaginal and cervical spermatozoa was compared. Periovulatory stumptailed macaque monkeys were administered intravaginally 1 ml of Ramses Contraceptive Vaginal Jelly (C. Schmid Products Company, Little Fall, NJ), or a pluronic gel formulation containing 0, 0.1, or 1.0% of a new spermicidal compound, RS-37367. All spermicide-containing formulations reduced the motility of both vaginal and cervical sperm, compared with the gel containing no spermicide. The 1.0% RS-37367 formulation was particularly effective. No motile spermatozoa were recovered from either location, and only 0.5% of the numbers of cervical spermatozoa recovered in control animals were recoverable from this treatment group (P less than 0.0003). The formulation containing 0.1% RS-37367 appeared to be bioequivalent to the Ramses formulation containing 5% nonoxynol-9. These in vivo results support previous in vitro comparisons in which RS-37367 was estimated to be 50 times as potent a spermatostatic agent as nonoxynol-9.


Assuntos
Anticoncepcionais Femininos/farmacologia , Imidazóis/farmacologia , Cremes, Espumas e Géis Vaginais/farmacologia , Animais , Muco do Colo Uterino/fisiologia , Feminino , Humanos , Macaca , Masculino , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermicidas/farmacologia , Espermatozoides/efeitos dos fármacos
7.
Fertil Steril ; 40(2): 231-6, 1983 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6307759

RESUMO

The spermatostatic potencies of a new vaginal contraceptive agent, RS-37367, and a standard surfactant compound, nonoxynol-9, have been compared by using ejaculated dog and human spermatozoa. RS-37367 was 25 to 50 times more potent than nonoxynol-9 against dog spermatozoa. Nonparallel concentration-response lines were obtained against human spermatozoa. Concentrations of RS-37367 causing immediate spermatostasis against dog spermatozoa resulted in vesiculation of the plasma and outer acrosomal membranes of spermatozoa; similarly, immediately spermatostatic concentrations of nonoxynol-9 were associated with the previously documented generalized membrane stripping. The activities of both RS-37367 and nonoxynol-9 were affected by the concentration of dog spermatozoa in semen-compound mixtures. Short-term (5-minute) exposure of spermatozoa to concentrations of RS-37367 not immediately spermatostatic resulted in progressive immobilization of spermatozoa. Extensive washing of the spermatozoa was not able to reverse this effect, in contrast to spermatozoa transiently exposed to nonoxynol-9.


Assuntos
Anticoncepcionais Femininos/farmacologia , Imidazóis/farmacologia , Polietilenoglicóis/farmacologia , Espermicidas/farmacologia , Animais , Cães , Humanos , Masculino , Nonoxinol , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos
8.
J Androl ; 8(4): 267-71, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3114204

RESUMO

Previous results, simultaneously confirmed by others, suggest that a relationship exists between sperm acrosin levels and fertility in man. The assessment of sperm acrosin may therefore be a useful addition to the semen analysis, but only if the more standard semen parameter measurements cannot predict acrosin levels. Ejaculates from 102 men were analyzed and the relationship of the sperm acrosin system (acrosin, proacrosin, and acrosin inhibitor) to other seminal characteristics was determined. Very little correlation was observed between enzymatic and nonenzymatic parameters. Only five non-enzymatic parameters, all of which were morphologic, showed correlation coefficients of greater than or equal to 0.35 with acrosin and proacrosin, but none had an r-value above 0.48. The total acrosin and proacrosin levels were highly correlated to each other (r = 0.93). It is concluded that sperm acrosin/proacrosin levels cannot be predicted by other seminal parameters; thus, measurement of sperm acrosin/proacrosin may be clinically useful as a diagnostic parameters.


Assuntos
Acrosina/análise , Endopeptidases/análise , Precursores Enzimáticos/análise , Sêmen/análise , Humanos , Infertilidade Masculina/fisiopatologia , Masculino , Espermatozoides/anormalidades
9.
J Androl ; 8(4): 230-7, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3624060

RESUMO

Within hours after administration of high oral doses of ketoconazole to males of various species, the intact compound appears in the seminal plasma, leading to immobilization of spermatozoa in ejaculates collected several hours later. The present report describes in vitro and in vivo characterization studies of several new compounds identified from a series of 1-substituted imidazole compounds. Relative rank order of in vitro potencies of the four compounds studied was RS-29984 greater than RS-90847 greater than RS-41353 greater than RS-68287. Oral administration of single doses of these compounds ranging between 10 and 95 mg/kg, followed by ejaculation of the animals at various times after dosing, showed that their relative potencies for decreasing sperm motility were RS-41353 greater than RS-68287 = RS-90847 greater than RS-29984. Four hours after animals were given 30 mg/kg of RS-41353, spermatozoa in the ejaculates had zero forward progression within 30 to 40 minutes after the start of ejaculation. A preliminary metabolic study indicated that the apparently greater potency of RS-68287 in vivo than in vitro was probably not due to metabolic activation. The androgen-suppressing activity of RS-29984 and RS-90847 was shown to be less than that of ketoconazole. These data indicate that orally active inhibitors of sperm motility that exert their effects after ejaculation may be feasible, and suggest that this novel approach to male contraception warrants further investigation.


Assuntos
Ejaculação , Sêmen/análise , Espermicidas/metabolismo , Administração Oral , Androgênios/sangue , Animais , Cães , Imidazóis/metabolismo , Cetoconazol/metabolismo , Masculino , Motilidade dos Espermatozoides , Espermicidas/administração & dosagem
10.
Contraception ; 26(5): 521-33, 1982 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6186431

RESUMO

Antifibrinolytic agents when released into the uterine cavity decrease menorrhagia associated with IUD use. Our objective was to develop a matrix that could be incorporated onto an IUD and release anti-fibrinolytic agents. The copolymer ethylene-vinyl acetate (EVA) was selected for detailed study because it has the advantage over other materials in that it can release large molecular weight substances for more than 100 days, and allows incorporation of large amounts of anti-fibrinolytic agents with different molecular weights. Two compounds, tranexamic acid (AMCA, MW=157) and Trasylol (Kunitz pancreatic trypsin inhibitor, (MW=6,500) were incorporated into the EVA matrix and their release rates measured. In vitro studies with AMCA showed that after the initial burst, a constant high release rate was obtained over a prolonged period of time. The in utero release rate of AMCA from the EVA matrix in rabbits was similar to that obtained in vitro. By contrast, the release rate of Trasylol decreased to low levels during incubation in vitro. The release rate of Trasylol in utero however, appeared to be higher than that in vitro.


Assuntos
Antifibrinolíticos/metabolismo , Dispositivos Intrauterinos Medicados , Menorragia/prevenção & controle , Polivinil/metabolismo , Animais , Aprotinina/metabolismo , Feminino , Técnicas In Vitro , Cinética , Métodos , Coelhos , Ácido Tranexâmico/metabolismo
11.
J Pediatr Endocrinol Metab ; 9(1): 9-19, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8887129

RESUMO

To determine the usefulness of a GnRH agonist analog as a diagnostic test to distinguish between constitutional delay of growth (CGD) in boys with Tanner stage I of sexual development and patients with hypogonadotropic hypogonadism (HH), we evaluated six boys (mean age 15 yr 4 m) and five HH patients (mean age 20 yr 4 m). In addition, 20 normal healthy men aged 21 yr to 50 yr received either nafarelin or GnRH followed two weeks later by the other test in order to compare the efficacy of each of these tests and to evaluate the optimal sampling times for the nafarelin test. All subjects were healthy, and had not received hormonal replacement for at least 2 months prior to enrollment in the study. Each man had four baseline blood samples before and at timed intervals following the administration of either GnRH or nafarelin. Each of the patients had blood withdrawn every 15 min during 12 h overnight followed by a single s.c. injection of nafarelin (1 microgram(s)/kg up to 100 microgram(s)), except two HH patients who did not have an overnight study. Blood samples were obtained at timed intervals for 24 h. LH, FSH, T and E2 were measured by RIA. Baseline concentrations of plasma LH, FSH and T were similar before the administration of either GnRH or nafarelin in the group of normal men. Peak stimulation of plasma LH, FSH and T released by nafarelin was significantly higher, and it took a longer time to reach the peak maximum, than after GnRH (p < 0.001). Mean nocturnal LH was 5.5 +/- 0.9 IU/I for the CGD group, and 2.7 +/- 0.7 IU/I for HH (p < 0.02). Mean nocturnal FSH was 5.1 +/- 1.0 and 2.5 +/- 0.2 IU/I whereas mean nocturnal T concentrations were 4.2 +/- 0.8 and 0.7 +/- 0.2 nmol/I (CGD vs HH, respectively, p < 0.02). Peak LH responses to nafarelin were 36.9 +/- 8.9 IU/I for the CGD group, and 7.0 +/- 2.0 IU/I for the HH group (p < 0.001). Peak FSH released by nafarelin was 14.2 +/- 2.4 IU/I for the CGD group and 4.8 +/- 2.0 IU/I for the HH group (p < 0.02). Peak T was reached 24 h following nafarelin injection and was 5.7 +/- 1.7 nmol/I for the CGD group and 0.3 +/- 0.2 nmol/I for the HH group (p < 0.001). The results obtained indicate that in early stages of puberty (before detectable changes of sexual maturation) the nafarelin test, with measurements of LH, FSH and T in blood or in urine, is superior to and more practical than overnight hormonal estimates to clearly distinguish CGD from HH.


Assuntos
Hormônio Liberador de Gonadotropina , Transtornos do Crescimento/diagnóstico , Hipogonadismo/diagnóstico , Nafarelina , Adulto , Ritmo Circadiano , Diagnóstico Diferencial , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/urina , Humanos , Hormônio Luteinizante/sangue , Hormônio Luteinizante/urina , Masculino , Pessoa de Meia-Idade , Puberdade Tardia , Testosterona/sangue
12.
Plast Reconstr Surg ; 78(6): 765-72, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3786530

RESUMO

This study of suction lipectomy aspirates from 15 consecutive patients was undertaken to biochemically quantitate the blood-to-fat ratios of the aspirates. A wide variation in the blood-to-fat ratios (8 to 54 percent) was noted, but the authors failed to demonstrate any relationship between the blood-to-fat ratios and the suction lipectomy operative site. Prophylactic measures to allow treatment of patients in a consistently safe manner include carefully screening of patients to exclude those with bleeding disorders or significant illnesses, perioperative oral iron therapy, infiltrating the operation site with a dilute epinephrine solution, hydrating the patients adequately perioperatively, using smaller-diameter cannulas for the aspiration, minimizing aspiration once the aspirate turns grossly bloody, and limiting the aspirate to a volume of less than 1750 ml for any operative procedure.


Assuntos
Tecido Adiposo/cirurgia , Tecido Adiposo/análise , Hemoglobinas/análise , Humanos , Lipídeos/análise , Sucção
13.
Aviat Space Environ Med ; 50(4): 357-62, 1979 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-464956

RESUMO

Eight human volunteers, individually studied in a hyperbaric chamber, breathed: 1) air at 1 ATA; 2) 80% argon and 20% oxygen and 1 ATA for 30 min; 3) air at 1 ATA for 30 min; 4) 100% 02 at 1 ATA for 30 min; 5) air at 1 ATA for 30 min; 6) 100% O2 at 2 ATA for 60 min; and 7) 80% argon and 20% oxygen at 1 ATA for 30 min. Oxygen, carbon dioxide, nitrogen, and argon tensions were measured in muscle and subcutaneous tissue by mass spectroscopic analyses. Venous blood obtained at regular intervals was analyzed for coagulation and fibrinolytic factors. Inert gas narcosis was not observed. After breathing argon for 30 min, muscle argon tensions were almost three times subcutaneous tensions. Argon wash-in mirrored nitrogen wash-out. Argon wash-in and wash-out had no effect on tissue Po2 or Pco2. Coagulation and fibrinolytic changes usually associated with vascular bubbles were absent.


Assuntos
Argônio , Dióxido de Carbono/metabolismo , Músculos/metabolismo , Nitrogênio/metabolismo , Consumo de Oxigênio , Oxigênio , Respiração , Pele/metabolismo , Adulto , Medicina Aeroespacial , Argônio/metabolismo , Coagulação Sanguínea , Humanos , Espectrometria de Massas , Pessoa de Meia-Idade
17.
Lab Anim Sci ; 37 Spec No: 132-3, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3626491

RESUMO

Management at Syntex is a corporate-wide policy which includes the humane care and treatment of laboratory animals. To that end, humane care and treatment of laboratory animals is a formal goal of all senior managers. Because Syntex wants the specific policies used to be corporate-wide, the AWC and ACC exist. The Committees act together to set policy, implement policy, and to satisfy federal regulations and societal concerns.


Assuntos
Bem-Estar do Animal , Indústria Farmacêutica , Comitê de Profissionais , Animais , Animais de Laboratório , Pesquisa
18.
Lab Anim Sci ; 32(2): 180-2, 1982 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7078087

RESUMO

A surgical procedure was developed which allowed for the long-term evaluation of the effect of candidate Foley catheter materials on urethral tissue. The dog provided a satisfactory animal model since, after being subjected to the described procedure, this animal remained continent and free of urinary tract infection. Also, each animal served as its own control by examining tissue from a portion of the urethra which was not in contact with the implanted material.


Assuntos
Cães , Modelos Biológicos , Uretra/patologia , Cateterismo Urinário/efeitos adversos , Animais , Cateteres de Demora/efeitos adversos , Estudos de Avaliação como Assunto , Hemorragia/etiologia , Masculino , Uretra/cirurgia
19.
Am J Physiol ; 237(1): E40-4, 1979 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-464051

RESUMO

Mouse spermatozoa possess a neutral proteinase, acrosin, that is to a large extent (70-80%) present in the zymogen (proacrosin) form. Acid extraction yields higher amounts of acrosin than detergent extraction. Synthetic inhibitor studies indicate that mouse acrosin has a serine and histidine at its active site and hydrolyzes the peptide bonds of lysine and arginine but of not phenylalanine. An inhibitor of acrosin is associated with mouse spermatozoa, capable of preventing the activity of at least 60% of all available acrosin. Acrosin activity is essential for fertilization because natural and synthetic inhibitors of mouse acrosin prevent the union of the gametes. Also, the relative inhibitory activity of synthetic agents toward acrosin runs approximately parallel to their antifertility activity. The percent of acrosin in the proacrosin form does not change after capacitating mouse spermatozoa in vitro.


Assuntos
Acrosina/metabolismo , Endopeptidases/metabolismo , Espermatozoides/enzimologia , Animais , Arginina/metabolismo , Benzamidinas , Inibidores Enzimáticos , Fertilização , Lisina/metabolismo , Masculino , Camundongos , Polietilenoglicóis , Capacitação Espermática
20.
J Reprod Fertil ; 63(2): 397-405, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6795347

RESUMO

Stability of the human sperm acrosin system (major components: non-zymogen acrosin, proacrosin and acrosin inhibitor) was studied under various conditions of semen storage used clinically or in the laboratory. Freezing at -196 degrees C caused a profound decrease in total acrosin content and in the amount of this enzyme present in zymogen form (proacrosin), but resulted in some increase in non-zymogen acrosin. Acrosin inhibitor did not appear to be significantly affected by this treatment. No relationship was present between the decreases in sperm motility induced by freezing to -196 degrees C and the alterations in total acrosin, proacrosin and non-zymogen acrosin. Storage of whole semen at -20 degrees C had deleterious effects on all the components of the acrosin system measured except for non-zymogen acrosin. Major decreases in the total acrosin, proacrosin and acrosin inhibitor occurred after only 1 day at -20 degrees C and continued slowly thereafter. Whole semen kept at room temperature for up to 24 h after ejaculation did not show any significant changes in the sperm acrosin system. Seminal plasma did not have a detrimental or stabilizing effect of acrosin and proacrosin when spermatozoa were kept at room temperature. However, removal of seminal plasma and re-suspension of spermatozoa in 0.9% NaCl resulted n the liberation of a significant amount of the acrosin inhibitor from the spermatozoa and the apparent activation of some of the proacrosin to acrosin.


Assuntos
Acrosina/metabolismo , Endopeptidases/metabolismo , Preservação do Sêmen , Espermatozoides/enzimologia , Precursores Enzimáticos/metabolismo , Congelamento , Humanos , Masculino , Temperatura
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