19 results on '"Brooks DE"'
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2. Characterization and androgen-dependence of proteins associated with luminal fluid and spermatozoa in the rat epididymis.
- Author
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Brooks DE and Higgins SJ
- Subjects
- Animals, Castration, Chromatography, Affinity, Electrophoresis, Polyacrylamide Gel, Male, Prealbumin biosynthesis, Rats, Sperm Maturation, Testosterone pharmacology, Albumins biosynthesis, Body Fluids metabolism, Epididymis metabolism, Spermatozoa metabolism
- Abstract
The proteins of epididymal luminal fluid and of spermatozoa recovered from different regions of the rat epididymis were examined by polyacrylamide gel electrophoresis under non-denaturing and denaturing conditions. Albumin (A) and four major pre-albumin bands (B-E) were observed in epididymal fluid from the cauda on non-denaturing gels. By comparing the migration of these bands with that of standard globular proteins on denaturing gels, the molecular weight of Bands B and C was estimated to be 16 000, Band D was 30 000 and Band E was 32 000. Bands D and E were apparently glycoproteins since they stained with periodic acid-Schiff's reagent and were bound by an affinity column of Concanavalin A. The pre-albumin proteins (B-E) were of epididymal origin since they (a) were not detected in blood serum, (b) were not detected in testicular extracts and (c) were still found after ligation of the efferent ducts. From the incorporation of radioactive methionine, Bands B and C were shown to be synthesized in the initial segment and caput. The regional distribution of luminal proteins indicated that protein D was added in the caput and cauda and protein E in the cauda. This regional origin of luminal proteins was confirmed by the altered protein profiles consequent upon the reduced fluid flow through the epididymis brought about by ligation of the efferent ducts. The androgen-dependence of epididymal protein synthesis was also investigated using radioactive methionine. Castration had little effect on total protein synthesis but resulted in the specific reduction of the synthesis of proteins B and C. Several changes were observed in the relative amounts of specific proteins extracted from spermatozoa from different regions of the epididymis and several of these proteins had molecular weights identical with those in luminal fluid. However, there was no evidence for any substantial binding to spermatozoa of the pre-albumin proteins (B-E) of luminal fluid.
- Published
- 1980
- Full Text
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3. Characterization of a 22 kDa protein with widespread tissue distribution but which is uniquely present in secretions of the testis and epididymis and on the surface of spermatozoa.
- Author
-
Brooks DE
- Subjects
- Animals, Ascitic Fluid, Cattle, Cross Reactions, Female, Male, Mice, Microscopy, Fluorescence, Molecular Weight, Rabbits, Rats, Saliva analysis, Sheep, Species Specificity, Surface Properties, Swine, Tissue Distribution, Uterus metabolism, Epididymis metabolism, Exudates and Transudates analysis, Proteins isolation & purification, Spermatozoa analysis, Testis metabolism
- Abstract
The purification is reported of a 22 kDa protein which was first identified as one of the major components of the luminal secretion of the rat testis and epididymis. Antibodies against the 22 kDa protein cross-reacted with a protein of the same molecular weight in cytosolic extracts of other tissues from both male and female rats. However, since the protein could not be detected in blood, peritoneal fluid, saliva, milk, uterine fluid, seminal vesicle secretion, coagulating gland secretion or prostatic secretion, it would appear that the testis and epididymis may be unique in containing the protein in a soluble form within their luminal secretions. Proteins with slightly lower molecular weight were detected by the antibodies in cytosolic extracts of tissues from other animals (mice, rabbits, sheep, pigs, cattle), indicating that the protein may be conserved in a variety of species. However, in contrast to the rat, the protein was apparently not present in the testicular and epididymal secretions of these species. In addition to the occurrence of the 22 kDa protein as a soluble moiety in rat testicular and epididymal fluids, the protein was also located on sperm plasma membranes where its distribution was restricted to the surface of the flagellum. Amongst sperm surface proteins, the 22 kDa protein was the major protein containing sulphydryl groups and one of the major entities containing disulphide bonds. These properties may be of importance in the maintenance of sperm viability.
- Published
- 1985
- Full Text
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4. Activity and androgenic control of enzymes associated with the tricarboxylic acid cycle, lipid oxidation and mitochondrial shuttles in the epididymis and epididymal spermatozoa of the rat.
- Author
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Brooks DE
- Subjects
- Androgens metabolism, Animals, Castration, Citric Acid Cycle, Lipid Metabolism, Male, Mitochondria enzymology, Rats, Testosterone pharmacology, Androgens physiology, Epididymis enzymology, Spermatozoa enzymology
- Abstract
1. Enzyme activities (units/g wet wt.) were determined in the caput and cauda epididymidis and in epididymal spermatozoa of the rat. 2. The activity of most enzymes in the cauda was between 50 and 100% of that in the caput, except that ATP citrate lyase was barely detectable in the cauda. 3. Spermatozoa, unlike epididymal tissue, contained sorbitol dehydrogenase but lacked ATP citrate lyase. NADP+-malate dehydrogenase, mitochondrial glycerol 3-phosphate dehydrogenase, succinate dehydrogenase, carnitine acetyltransferase and citrate synthase were 5 to 400 times as active in spermatozoa as in epididymal tissue. 4. 2-Oxoglutarate dehydrogenase was the least active member of the tricarboxylic acid cycle in all tissues and most closely matched the measured flux through the cycle. 5. The concentrations of hydroxyacyl-CoA dehydrogenase and carnitine palmitoyltransferase were equivalent to the more active enzymes of the tricarboxylic acid cycle, indicating the capacity for extensive lipid oxidation, and the presence of 3-hydroxybutyrate dehydrogenase suggests that these tissues can also oxidize ketone bodies. 6. Transfer of reducing equivalents from cytoplasm to mitochondrion is unlikely to occur by means of the glycerol phosphate cycle because mitochondrial glycerol 3-phosphate dehydrogenase is relatively inactive in epididymal tissue, whereas the cytoplasmic enzyme has little activity in spermatozoa, but transfer may be accomplished by the malate-aspartate shuttle. 7. Transfer of acetyl units from mitochondrion to cytoplasm could be effected by the pyruvate-malate cycle in the caput of androgen-maintained rats, but not in the other tissues because of the low activity of ATP citrate lyase. Acetyl unit transfer could take place via acetylcarnitine, mediated by carnitine acetyltransferase. 8. Castration resulted in a decrease in the concentration of nearly all enzymes, although subsequent administration of testosterone restored concentrations to values similar to those in animals maintained by endogenous androgen. The extent to which enzyme concentration was changed by an alteration in androgen status was highly variable, but was most marked in the case of pyruvate carboxylase.
- Published
- 1978
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5. Activity and androgenic control of glycolytic enzymes in the epididymis and epididymal spermatozoa of the rat.
- Author
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Brooks DE
- Subjects
- Animals, Epididymis drug effects, Fructose-Bisphosphate Aldolase metabolism, Glucose-6-Phosphate Isomerase metabolism, Glucosephosphate Dehydrogenase metabolism, Glyceraldehyde-3-Phosphate Dehydrogenases metabolism, Glycerolphosphate Dehydrogenase metabolism, Hexokinase metabolism, L-Lactate Dehydrogenase metabolism, Male, Phosphofructokinase-1 metabolism, Phosphogluconate Dehydrogenase metabolism, Phosphoglycerate Kinase metabolism, Phosphoglycerate Mutase metabolism, Phosphopyruvate Hydratase metabolism, Pyruvate Kinase metabolism, Pyruvates pharmacology, Rats, Spermatozoa drug effects, Triose-Phosphate Isomerase metabolism, Epididymis enzymology, Glycolysis, Spermatozoa enzymology, Testosterone pharmacology
- Abstract
1. Procedures were developed for the extraction and assay of glycolytic enzymes from the epididymis and epididymal spermatozoa of the rat. 2. The epididymis was separated into four segments for analysis. When rendered free of spermatozoa by efferent duct ligation, regional differences in enzyme activity were apparent. Phosphofructokinase, glycerol phosphate dehydrogenase and glucose 6-phosphate dehydrogenase were more active in the proximal regions of the epididymis, whereas hexokinase, lactate dehydrogenase and phosphorylase were more active in the distal segment. These enzymes were less active in the epididymis of castrated animals and less difference was apparent between the proximal and distal segments. However, the corpus epididymidis from castrated rats had lower activities of almost all enzymes compared with other epididymal segments. 3. Spermatozoa required sonication to obtain satisfactory enzyme release. Glycolytic enzymes were more active in spermatozoa than in epididymal tissue, being more than 10 times as active in the case of hexokinase, phosphoglycerate kinase and phosphoglycerate mutase. 4. The specific activities of a number of enzymes in the epididymis were dependent on the androgen status of the animal. These included hexokinase, phosphofructokinase, aldolase, glyceraldehyde phosphate dehydrogenase, phosphoglycerate kinase, pyruvate kinase, glycerol phosphate dehydrogenase, glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and phosphorylase. 5. The caput and cauda epididymidis differed in the extent to which enzyme activities changed in response to an altered androgen status. The most notable examples were hexokinase, phosphofructokinase, aldolase, phosphoglycerate kinase, 6-phosphogluconate dehydrogenase and phosphorylase.
- Published
- 1976
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6. Analysis of surface proteins of rat spermatozoa during epididymal transit and identification of antigens common to spermatozoa, rete testis fluid and cauda epididymal plasma.
- Author
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Brooks DE and Tiver K
- Subjects
- Animals, Antigens immunology, Body Fluids metabolism, Electrophoresis, Polyacrylamide Gel, Iodine Radioisotopes, Male, Membrane Proteins blood, Membrane Proteins immunology, Rats, Rats, Inbred Strains, Rete Testis metabolism, Spermatozoa immunology, Testis immunology, Epididymis physiology, Membrane Proteins metabolism, Sperm Transport, Spermatozoa metabolism
- Abstract
Spermatozoa from the testis and cauda epididymidis of the rat were surface labelled with radioactive iodide, extracted with detergent, and the radioactive proteins separated by two-dimensional polyacrylamide gel electrophoresis. In some instances spermatozoa were also surface labelled with tritiated borohydride in the presence of galactose oxidase. Soluble proteins in blood serum, rete testis fluid and cauda epididymal plasma were also iodinated and separated by gel electrophoresis. In addition, aliquants of the radioactive sperm extracts, blood serum and reproductive tract fluids were each immunoprecipitated with polyspecific antisera directed against either testicular sperm membranes, caudal sperm membranes, blood serum, rete testis fluid or cauda epididymal plasma before gel electrophoresis. From the patterns of radioactive proteins detected on the resultant gels, a two-dimensional map was created for each of the sperm extracts and for the various fluids. Proteins which were nonhomologous between testicular and caudal spermatozoa were identified, as well as proteins which were common to spermatozoa and reproductive tract fluids. Epididymal transit was characterized by the loss of certain proteins from the sperm surface, including three borohydride-labelled proteins of Mr 130 000, and by the addition of others, most notably a highly abundant protein of Mr 42 000. Several of the proteins lost from spermatozoa accumulated in the epididymal plasma whilst some of those added to the sperm surface could be identified as direct secretory products of the epididymis. Rete testis fluid contained blood proteins in addition to others presumed to be testis-specific, whilst the composition of cauda epididymal plasma was markedly different from blood serum or rete testis fluid.(ABSTRACT TRUNCATED AT 250 WORDS)
- Published
- 1984
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7. Localization of epididymal secretory proteins on rat spermatozoa.
- Author
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Brooks DE and Tiver K
- Subjects
- Animals, Electrophoresis, Polyacrylamide Gel, Fluorescent Antibody Technique, Male, Microscopy, Fluorescence, Molecular Weight, Proteins metabolism, Rats, Rats, Inbred Strains, Epididymis metabolism, Sperm Head analysis, Spermatozoa analysis, Testicular Hormones isolation & purification
- Abstract
Spermatozoa from the testis and cauda epididymidis of the rat were surface labelled with radioactive iodide. Detergent extracts of radioiodinated spermatozoa immunoprecipitated with antisera against specific epididymal proteins, followed by polyacrylamide gel electrophoresis, revealed two proteins (D and E of Mr 27 000 and 28 000, respectively) which became associated with spermatozoa during epididymal transit. These proteins were observed by immunofluorescence microscopy to be located over a restricted area of the head surface. Proteins with similar molecular weight were labelled on spermatozoa from the cauda epididymidis, but not from the testis, by reaction with sodium boro[3H]hydride in the presence of galactose oxidase. However, failure to immunoprecipitate with antibodies to Proteins D and E and non-coincident migration on two-dimensional gel electrophoresis established the non-identity of these proteins. Compared with Proteins D and E, two other major epididymal secretory proteins (Proteins B and C of Mr 16 000) associated with spermatozoa to a relatively minor extent during epididymal transit.
- Published
- 1983
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8. D(--)-lactic acid and d(--)-lactate dehydrohgenase in octopus spermatozoa.
- Author
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Mann T, Martin AW, Thiersch JB, Lutwak-Mann C, Brooks DE, and Jones R
- Subjects
- Anaerobiosis, Animals, Electrophoresis, Hydrogen-Ion Concentration, L-Lactate Dehydrogenase metabolism, Lactates metabolism, Male, NAD metabolism, Pyruvates metabolism, Species Specificity, Spermatozoa enzymology, Spermatozoa metabolism, Stereoisomerism, L-Lactate Dehydrogenase analysis, Lactates analysis, Octopodiformes metabolism, Spermatozoa analysis
- Abstract
The spermatozoa of Octopus dofleini martini produce anaerobically D(-)-lactic acid and possess a very active D(-)-lactate dehydrogenase. In this respect, while resembling certain microorganisms, they differ strikingly from mammalian spermatozoa which produce L(+)-lactic acid and contain L(+)-lactate dehydrogenase.
- Published
- 1974
- Full Text
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9. Androgen-regulated epididymal secretory proteins associated with post-testicular sperm development.
- Author
-
Brooks DE
- Subjects
- Animals, Cloning, Molecular, Cross Reactions, Epididymal Secretory Proteins, Gene Expression Regulation, Male, Molecular Weight, Orchiectomy, Protein Conformation, RNA, Messenger genetics, Rats, Testicular Hormones immunology, Tissue Distribution, Androgens physiology, Epididymis physiology, Sperm Maturation, Spermatozoa physiology, Testicular Hormones physiology
- Abstract
A considerable body of information has now been assembled with regard to the major androgen-dependent secretory proteins of the rat epididymis. The proteins have been purified, specific antibodies have been developed against them, and their primary structure has been determined from cDNA clones. The antibody and cDNA probes have, in turn, been used to study the androgenic regulation of the synthesis and secretion of the proteins, the distribution of the proteins in various tissues and animal species, and the association of the proteins with the sperm surface during epididymal maturation. Despite this intensive effort, the precise physiological functions of the proteins still remain obscure, although circumstantial evidence indicates that glycoproteins D and E may be associated with surface receptors responsible for gamete recognition. Elucidation of the physiological roles of the proteins is clearly the area that warrants the greatest attention in future work.
- Published
- 1987
- Full Text
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10. Carnitine, acetylcarnitine and the activity of carnitine acyltransferases in seminal plasma and spermatozoa of men, rams and rats.
- Author
-
Brooks DE
- Subjects
- Acetylcarnitine analysis, Animals, Carnitine O-Palmitoyltransferase metabolism, Humans, Male, Rats, Semen enzymology, Sheep, Spermatozoa enzymology, Acyltransferases metabolism, Carnitine analysis, Carnitine Acyltransferases metabolism, Semen analysis, Spermatozoa analysis
- Abstract
The concentration of total carnitine (i.e. carnitine plus acetylcarnitine) was measured in seminal plasma and spermatozoa of men and rams. In ram semen, there was a close correlation between the concentration of spermatozoa and that of total carnitine in the seminal plasma, indicating that the epididymal secretion was the sole source of seminal carnitine. The percentage of total carnitine present as acetylcarnitine was 40% in seminal plasma and 70-80% in spermatozoa. The acetylation state of carnitine in seminal plasma was apparently not influenced by the metabolic activity of spermatozoa in ejaculated ram semen as no change was found in the plasma concentration of carnitine or acetylcarnitine up to 45 min after ejaculation. In spermatozoa, the activity of carnitine acetyltransferase (EC 2.3.1.7) was approximately equivalent to that of carnitine palmitoyltransferase (EC 2.3.1.21); and the activity of these enzymes was similar in ram and human spermatozoa but greater in rat spermatozoa. It is concluded that there is no correlation between the content of either total carnitine or the carnitine acyltransferases and the respiratory capacity of spermatozoa.
- Published
- 1979
- Full Text
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11. Entry of glycerol into the rat epididymis and its utilization by epididymal spermatozoa.
- Author
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Cooper TG and Brooks DE
- Subjects
- Animals, Body Fluids metabolism, Glycerol blood, Male, Oxygen Consumption, Perfusion, Rats, Epididymis metabolism, Glycerol metabolism, Spermatozoa metabolism
- Abstract
The availability of glycerol in the epididymal lumen, and the extent of its utilization by spermatozoa, was studied by measurement of the substrate concentration in epididymal fluid and its oxidation in vitro. The source of luminal glycerol was sought by examining its penetration through the epididymal epithelium of a sperm-free tubule by the technique of luminal perfusion during intravenous infusion of glycerol. [3H]Glycerol was rapidly metabolized to a volatile and mobile molecule that quickly equilibrated between blood plasma and the epididymal lumen and so could not be used to monitor transfer. When blood levels of glycerol were raised by infusion of large amounts of the unlabelled compound, glycerol was detected in epididymal perfusates and a positive linear correlation existed between the rate of secretion into the epididymal lumen and the blood plasma concentration, suggesting that passive diffusion across the epithelium from blood could occur. In normal rats, however, the concentration of glycerol in sperm-free epididymal fluid (1.15 mM) exceeded that in blood plasma (0.35 mM). Luminal glycerol is therefore thought to arise from degradation of epididymal lipid.
- Published
- 1981
- Full Text
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12. Composition of gangliosides from ovine testis and spermatozoa.
- Author
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Gore PJ, Singh SP, and Brooks DE
- Subjects
- Animals, Carbohydrates analysis, Chromatography, High Pressure Liquid, Chromatography, Thin Layer, Fatty Acids analysis, Fucose analysis, Male, Sheep, Sialic Acids analysis, Gangliosides analysis, Spermatozoa analysis, Testis analysis
- Abstract
Gangliosides were extracted and purified from ovine testis and ejaculated spermatozoa which contained, respectively, 57 and 9 nmol lipid-bound sialic acid per gram wet weight. Fourteen gangliosides were resolved by thin-layer chromatography of testicular gangliosides, of which eleven were purified in sufficient quantity to enable a complete compositional analysis of the carbohydrate residues to be performed. None of the gangliosides contained fucose, but several contained N-glycolylneuraminic acid as a component of the sialic acid species. Relative migration on thin-layer chromatograms relative to known standards, compositional analysis, and selective degradation by specific enzymes were used as the basis for identification. Testis contained members of the ganglio series (GM1, GD1a, GD1b, GT1b, GQ1b), hematoside series (GM3, GD3), and sialosylparagloboside in the molar ratio of 54:40:6, respectively. Testicular GM3, GM1, GD3, GD1a, GD1b and GT1b ran as double bands on thin-layer chromatography which could be accounted for by observed differences in the fatty acid moiety. In addition, the slower migrating band of each pair contained some or all of its sialic acid residues as N-glycolylneuraminic acid, whereas the faster migrating band contained exclusively N-acetylneuraminic acid, except for GM3 where N-acetylneuraminic acid was the sole species in both bands. Thin-layer chromatography of sperm gangliosides revealed seven bands comigrating with equivalent testicular gangliosides. These coincided with the slower migrating bands of testicular GM3, GM1, GD3, GD1a, both bands of GD1b, and possibly both bands of GT1b. Sperm contained only trace amounts of sialosylparagloboside but, in addition, two unidentified bands which were absent from testis were also observed. The molar ratio of the ganglio series to the hematoside series in sperm was 42:58 with GM3 accounting for 42% of total gangliosides.
- Published
- 1986
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13. NAD in the metabolism of motile spermatozoa.
- Author
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Brooks DE and Mann T
- Subjects
- Cell Movement, Fructose pharmacology, Lactates pharmacology, Male, NAD analysis, Oxidation-Reduction, Oxidoreductases, Pyruvates pharmacology, Semen analysis, Semen metabolism, Spermatozoa analysis, Spermatozoa drug effects, Spermatozoa enzymology, NAD metabolism, Spermatozoa metabolism
- Published
- 1971
- Full Text
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14. Nucleotides in spermatozoa.
- Author
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Brooks DE
- Subjects
- Adenosine Triphosphate analysis, Animals, Cattle, Cyanides pharmacology, Dinitrophenols pharmacology, Horses, Male, Sheep, Spermatozoa drug effects, Swine, Adenine Nucleotides analysis, Spermatozoa analysis
- Published
- 1971
- Full Text
- View/download PDF
15. Observations on the content of ATP and ADP in bull spermatozoa using the firefly luciferase system.
- Author
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Brooks DE
- Subjects
- Animals, Buffers, Cattle, Centrifugation, Ejaculation, Firefly Luciferin, Fructose, Glycolysis, Male, Oxygen, Semen analysis, Sodium Chloride, Suspensions analysis, Adenine Nucleotides analysis, Adenosine Triphosphate analysis, Luciferases, Spermatozoa analysis
- Published
- 1970
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16. Motility and energy-rich phosphorus compounds in spermatozoa of Octopus dofleini martini.
- Author
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Brooks DE, Lutwak-Mann C, Mann T, and Martin AW Jr
- Subjects
- Adenine Nucleotides metabolism, Adenosine Triphosphate metabolism, Animals, Cell Movement, Male, Mollusca, Nucleotides metabolism, Spermatozoa
- Published
- 1971
- Full Text
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17. Relation between the oxidation state of nicotinamide-adenine dinucleotide and the metabolism of spermatozoa.
- Author
-
Brooks DE and Mann T
- Subjects
- Acetoacetates pharmacology, Alcohol Oxidoreductases isolation & purification, Anaerobiosis, Animals, Carbon Dioxide metabolism, Cattle, Chickens, Horses, In Vitro Techniques, Lactates pharmacology, Male, NAD analysis, NADP isolation & purification, Oxidation-Reduction, Oxygen, Pyruvates pharmacology, Sheep, Sorbitol pharmacology, Spermatozoa analysis, Spermatozoa enzymology, Swine, Temperature, NAD metabolism, Spermatozoa metabolism
- Abstract
1. The existing procedures for extraction of oxidized and reduced nicotinamide coenzymes were adapted to spermatozoa to overcome the coenzyme-degrading activity of seminal plasma. 2. The content of total NAD(+) and NADH was determined in the spermatozoa of ram, bull, boar, stallion and cock. NADP(+) and NADPH were not detected in ram spermatozoa. 3. The oxidation state of sperm NAD depended on the seminal plasma, the removal of which produced a change in the percentage oxidation state of the coenzyme, 100x[NAD(+)/(NAD(+)+NADH)], without altering the total content of NAD(+)+NADH. 4. In suspensions of washed ram spermatozoa, incubated anaerobically at 25 degrees C, the percentage oxidation state of NAD declined with increasing spermatozoa concentration. 5. When ram or boar spermatozoa that had been previously washed and resuspended in Ringer phosphate medium, were incubated anaerobically at 25 degrees C with various substances, pronounced effects on the percentage oxidation state of NAD could be observed with l-lactate, pyruvate, oxaloacetate, dihydroxyacetone, formaldehyde and glyceraldehyde; sorbitol and acetoacetate acted only on ram spermatozoa; fructose, glucose, mannose and acetaldehyde acted predominantly on boar spermatozoa. Formaldehyde lowered the (NAD(+)+NADH) content of ram spermatozoa, but none of the other substances had a comparable effect. 6. The percentage oxidation state of sperm NAD was not influenced by exogenous cysteine, cystine, ergothioneine or ascorbate. 7. A highly active sorbitol dehydrogenase could be prepared from ram, but not from boar, spermatozoa. 8. Sorbitol, acetoacetate and 3-hydroxybutyrate effectively supported the respiration of ram, but not boar, spermatozoa. 9. ;Cold shock', resulting from sudden cooling of spermatozoa, abolished motility completely and irreversibly but produced only a slow and partial decrease in the total NAD content. Slight over-heating, sufficient to produce loss of motility, had no adverse effect on the total NAD content. 10. Storage of ram sperm at 14 degrees C produced only a small decrease of NAD after 2 days, but subsequently the loss became greater.
- Published
- 1972
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18. Pyruvate metabolism in boar spermatozoa.
- Author
-
Brooks DE and Mann T
- Subjects
- Acetates biosynthesis, Acetoacetates biosynthesis, Aerobiosis, Animals, Carbon Dioxide biosynthesis, Cold Temperature, Fructose metabolism, Immobilization, Lactates biosynthesis, Male, Succinates biosynthesis, Swine, Vibration, Pyruvates metabolism, Spermatozoa metabolism
- Published
- 1973
- Full Text
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19. Epididymal functions and their hormonal regulation
- Author
-
Brooks De
- Subjects
Male ,medicine.medical_specialty ,Lumen (anatomy) ,Biology ,Androgen-Binding Protein ,Endocrinology ,Internal medicine ,Genetics ,medicine ,Animals ,Humans ,General Materials Science ,Secretion ,Receptor ,Molecular Biology ,Sperm motility ,Epididymis ,Mammals ,Sodium ,Proteins ,Dihydrotestosterone ,General Medicine ,Sperm ,Glycerylphosphorylcholine ,Spermatozoa ,Hormones ,Rats ,Sperm Transport ,Sperm Maturation ,Secretory protein ,medicine.anatomical_structure ,Reproductive Medicine ,Receptors, Androgen ,Protein Biosynthesis ,Androgens ,Sperm Motility ,Animal Science and Zoology ,Cattle ,Developmental Biology ,Biotechnology ,Hormone ,Protein Binding - Abstract
The epididymis is a complex organ which maintains a specific intraluminal environment thought to be important for effecting sperm maturation in proximal regions and sperm storage in distal regions of the duct. The composition of the internal milieu is achieved both by transport between blood and lumen (and vice versa) and by synthesis and secretion into the lumen. Several low-molecular weight organic molecules achieve high concentration in the epididymal lumen, but their functions in the events of sperm maturation and storage still remain unclear. Metabolic processes occurring within epididymal tissue and the absorptive and secretory activity of the epididymal epithelium are regulated by androgens. The synthesis of some, but not all, secretory proteins is also androgen-dependent. In addition to androgens, other hormones and local testicular factors may influence epididymal function. There is now increasing evidence that epididymal-specific and androgen-dependent secretory proteins play a fundamental role in modifying the surface characteristics of sperm in preparation for the events of fertilization.
- Published
- 1983
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