Age-related changes in the seminal vesicles of a Brazilian (Nelore) zebu.

Age changes in the structure of the seminal vesicles and in the rate of production of fructose and citric acid have been studied in a Brazilian (Nelore) zebu, from the fetal period to 36 months of age. At 3 and 6 months, the microscopic anatomy of the gland resembled that of the fetus; the tubules of the seminal vesicles had a reduced diameter and a low epithelial layer; only a few presented traces of secretion, and tissue contents of fructose and citric acid were accordingly low. At 12 months, the tubules were more ramified and had a larger diameter. In the 18-month-old animals the seminal vesicles presented substantial modifications; the tubules were large, with irregular lumina and surrounded by narrow stroma, the epithelial layer was higher than that of previous stages and its columnar cells had nuclei located basally. Tissue levels of fructose increased rapidly between 12 and 18 months. At 24 months, the seminal vesicles had reached the adult condition characterized by intense proliferation of tubules with irregular lumina and abundant secretory material. Numerous dark columnar cells were found in the epithelium. Seminal vesicles of Nelore zebus contain less fructose and citric acid than those of taurine bulls of comparable age.     

Studies of chemical components of Angora goat seminal plasma

Ejaculates were collected by artificial vagina from 11 Angora goats, once or twice weekly, between April and July in two successive years. The mean +/- SEM ejaculate volumes each year were 0.8 +/- 0.30 and 0.98 +/- 0.52 ml; the sperm concentrations were 3.33 +/- 0.49 and 2.94 +/- 0.45 x 10(9)/ml, and the pH values were 7.01 +/- 0.34 and 7.20 +/- 0.17. The concentrations (mg/100ml) of fructose (875 +/- 97) and lactic acid (73 +/- 17) in goat seminal plasma were sufficiently high to be important substrates for maintenance of sperm motility. Only trace amounts of glucose were present in seminal plasma. The glycerylphosphorylcholine (GPC) concentration of seminal plasma (809 +/- 154 mg 100 ml ) was correlated with whole semen sperm concentration (P < 0.001), indicating that GPC is of epididymal origin. Goat sperm are not likely to utilize GPC as a substrate and its metabolizable derivatives, glycerophosphate (3.3 +/- 1.1 mg 100 ml ) and glycerol (1.8 +/- 1.0 mg 100 ml ), were not present in sufficiently high concentrations to be significant as energy sources for the sperm. The mean concentration of citric acid was 331 mg 100 ml seminal plasma. Colored semen was consistently produced by eight bucks, and in yellow, light yellow and white ejaculates, the seminal plasma riboflavin (mug/ml) concentrations were 5.38 +/- 2.89, 3.09 +/- 0.85 and 1.73 +/- 0.88, respectively. This suggests that the color is due to riboflavin, which is probably produced by the vesicular glands since the concentration of riboflavin in the seminal plasma was correlated with fructose and citric acid levels.     

Testosterone concentration in testicular venous blood of adult rats and seminal citric acid and fructose concentration as well as weight of accessory sex organs.

In 31 adult rats of Wistar strain (body weight 231 +/- 14g) the relationships between testosterone concentration in testicular venous blood of an individual rat and weight of accessory sex organs (testes, seminal vesicles, ventral prostate, levator ani muscle) and citric acid and fructose concentrations in seminal vesicles were investigated. No direct relationship was found between testosterone concentration and the above parameters. The correlation coefficient varied from 0.042 to 0.394.     

Composition of the milt of some teleost fishes

The milt composition of six freshwater teleosts was studied, and the measured parameters showed clear specific differences between species. The highest spermatocrits and sperm densities were observed in perch, Perc afluviatilis , and burbot, Lota lota , and the lowest in rainbow trout, Salmo gairdneri , and whitefish, Coregonus lavaretus . Fructose concentrations in the seminal plasma were small compared to mammalian values. The glucose concentrations in the seminal plasma were five times higher than those of fructose, and higher in landlocked salmon and rainbow trout than in the other species. The citric acid concentration of all species except whitefish showed a significantly positive correlation to either spermatocrit or sperm density. The role of citric acid in the seminal plasma of fishes was also assumed to be important. The glycerol concentration in the seminal plasma was comparatively high, and highest in whitefish. This was assumed to be related to the high applicability value of glycerol as a cryoprotective agent for whitefish sperm. The high glycerol concentration was also assumed to be related to the lipolytic capacity of the testis in the studied species.     

Catalase activity in human spermatozoa and seminal plasma

Catalase activity was determined in human semen by measuring the oxygen burst with a Clark electrode, after H₂O₂ addition. Significant catalase activities (mean ± SD) were found in migrated, motile spermatozoa (44 ± 17 nmoles O₂/min/10⁸ cells) and in seminal plasma of normozoospermic men (129 ± 59 nmoles O₂/min/ml). It has been demonstrated that seminal catalase originated from prostate; however, its activity was not correlated with the usual prostatic markers (such as citric acid and zinc). Our data suggest a multiglandular function secreted by this organ. The catalase activities measured in seminal samples from asthenozo-ospermic, infertile men were found lower than those from normozoospermic subjects. The understanding of the relative contribution of the different enzyme systems against O₂ toxicity (superoxide dismutase, catalase, glutathione peroxidase) seem to be a priority area of research to understand disturbances of sperm function.     

Extraction of the synthetic lytic peptide,cecropin B,from biological fluid and analysis using reversed-phase high-performance liquid chromatography

The lytic peptide cecropin B, originally isolated from the giant silk moth Hyalophora cecropia, has been found to possess antibacterial and cell lysis properties in vitro and some anticancer activity in vivo. An HPLC method was developed to study synthetic cecropin B concentrations in biological fluids. Cecropin B was recovered from culture medium by solid-phase extraction (40.0 ± 2.4%), whereas in plasma it was highly protein-bound. The peptide was dissociated from proteins by citric acid and recovered by ultrafiltration (64.6 ± 5.9%) and was unstable in plasma (half-life, 0.57 ± 0.11 h). These analytical methods will facilitate future in vivo pharmacokinetic studies.     

Permeability of the blood-brain barrier to fructose and the anaerobic use of fructose in the brains of young mice

—Fructose levels were determined in plasma and brain of 8- to 12-day-old mice at intervals after the injection of 30 mmol/kg intraperitoneally; controls received NaCl, 15 mmol/kg. In normal animals brain fructose increased very slowly despite a rapid rise in plasma levels (120 times the control value in 5 min). At 40 min the cerebral level was 1.54 ± 0.23 mmol/kg; the corresponding plasma level was 47.1 ± 4.8 mM. The data suggest that fructose can serve as a source of energy to the brain in times of critical need: during insulin hypoglycemia brain fructose increased to only 0.88 ± 0.05 mmol/kg during the same interval (40 min) despite plasma fructose values equal to those in control animals; also 30 s after cerebral ischemia (decapitation) brain fructose fell from a zero time value of 1.19 ± 0.09 mmol/kg (20 min after fructose injection) to 0.76 ± 0.06 mmol/kg (P= 0.005). Under both circumstances (hypoglycemia and ischemie anoxia) an apparent threshold concentration of fructose for utilization was observed—0.6–0.7 mmol/kg. The most likely explanation for this finding appears to be that this level of fructose was in the extracellular space of the brain. Hexokinase activity in brain homogenates of 8- to 12-day-old mice with fructose and ATP at concentrations found in vivo and during ischemie anoxia did not appear to be rate-limiting. We concluded that the major handicap to the use of fructose by the brain was the limited penetration of fructose from the blood to the brain.     

Subsequent effect of subacute T-2 toxicosis on spermatozoa, seminal plasma and testosterone production in rabbits

Pannon White (n=12) male rabbits (weight: 4050 to 4500 g, age: 9 months) received 2 ml of a suspension containing purified T-2 toxin by gavage for 3 days. The daily toxin intake was 4 mg/animal (0.78 to 0.99 mg/kg body weight (BW)). Control animals (n=12) received toxin-free suspension for 3 days. Since a feed-refusal effect was observed on the second day after T-2 administration, a group of bucks (n=10) were kept as controls (no toxin treatment) but on a restricted feeding schedule, that is, the same amount of feed was provided to them as was consumed by the exposed animals. On day 51 of the experiment (i.e. 48 days after the 3-day toxin treatment), semen was collected, and pH, concentration, motility and morphology of the spermatozoa, as well as concentration of citric acid, zinc and fructose in the seminal plasma, were measured. After gonadotropin-releasing hormone (GnRH) analogue treatment, the testosterone level was examined. One day of T-2 toxin treatment dramatically decreased voluntary feed intake (by 27% compared to control, P<0.05) and remained lower (P<0.05) during the first 2 weeks after the withdrawal of the toxin. BW of the contaminated rabbits decreased by 88% on days 17 and 29 compared to controls (P<0.05). No effect of toxin treatment was detected on pH and quantity of the semen or concentration of spermatozoa. The ratio of spermatozoa showing progressive forward motility decreased from 65% to 53% in the semen samples of toxin-treated animals compared to controls (P>0.05). The ratio of spermatozoa with abnormal morphology increased (P<0.05) in the ejaculates collected from the toxin-treated animals. T-2 toxin applied in high doses decreased the concentration of citric acid in seminal plasma (P<0.05). No effect of T-2 toxin on the concentrations of the other seminal plasma parameters (fructose and zinc) was observed. T-2 toxin decreased the basic testosterone level by 45% compared to control (P<0.01) and resulted in lower (P<0.05) GnRH-induced testosterone concentration. Feed restriction, that is, less nutrient intake, resulted in more morphologically abnormal spermatozoa in the semen, but it did not cause significant loss in BW, motility of the spermatozoa, composition of the seminal plasma or testosterone concentration--its effect needs further examination.     

Spermatozoa motility and variation in the seminal plasma proteome of Eurasian perch (Perca fluviatilis) during the reproductive season

This study evaluated physiological and functional sperm parameters and the seminal plasma proteome of Eurasian perch (Perca fluviatilis) over the course of their reproductive season. Spermatozoa velocity (169.56 ± 6.53 to 158.5 ± 7.4 µm sec^?1), percent motility (95.89 ± 4.28% to 89.55 ± 4.5%), and osmolality of seminal plasma (290 ± 5 to 297 ± 12 mOsmol kg^?1) remained stable throughout the reproductive season. Milt volume and protein concentration of seminal plasma gradually increased and reached the highest values late in the reproductive period. Spermatozoa concentration peaked in the mid‐reproductive season (66.90 ± 13 × 10⁹ spermatozoa ml^?1) and decreased towards the end (54 ± 10 × 10⁹ spermatozoa ml^?1). A proteomic analysis of seminal plasma using two‐dimensional polyacrylamide gel electrophoresis revealed 10 protein spots significantly altered over the course of the reproductive season. Subsequent protein characterization suggested that time in the reproductive season predominantly affected proteins involved in membrane trafficking, organization, cell motility, and oxido‐reductase activity. This study provides new data on physiological properties of sperm and protein patterns of seminal plasma over the course of the reproductive season that should be considered in the development of methods for artificial reproduction of perch. Mol. Reprod. Dev. 79: 879–887, 2012. © 2012 Wiley Periodicals, Inc.     

The testicular main ducts and the spermatic ducts in some cyprinid fishes—II. Composition of the seminal fluid

The composition of the organic compounds of the seminal fluid, pH values and osmolalities were investigated in three cyprinid species, the bleak ( Alburnus alburnus ), the chub ( Leuciscus cephalus ) and the zaehrte ( Vimba vimba ). The seminal fluid contains monosaccharides (glucose, fructose, galactose, xylose), lipids (cholesterol, fatty acids, phosphatidylcholine, glycolipids) and proteins, and exhibits activities of acid phosphatase, β-glucuronidase, proteases and to some extent of alkaline phosphatase. The composition of free amino acids reveals species specific differences.     

Biochemical composition of washed human seminal coagulum in comparison to sperm-free semen from the same donors

Intra-individual inter-ejaculate variations in the amounts of protein, fructose, N-acetylamino sugar, phosphate, sialic acid and amino sugar in washed coagulum from normal ejaculates of men were highly consistent (N = 9). All the prostatic components studied (acid phosphatase, zinc, calcium and citric acid), except zinc, in the washed coagulum were reduced by 90% of their values in semen (N = 5). The seminal vesicular markers (fructose, N-acetylamino sugar and phosphate) had no association with the coagulum structure and represented the soluble components (N = 5). The concentrations of protein and zinc in the coagulum were higher than those of semen by 114% and 32% respectively. The coagulum contained sialic acid and amino sugar as integrated components.     

Reversion of thermic-shock effect on ram spermatozoa by adsorption of seminal plasma proteins revealed by partition in aqueous two-phase systems

Centrifugal counter-current distribution (CCCD) in a dextran, Ficoll, poly(ethylene glycol) two-phase system was used to study the effect of seminal plasma proteins on the partition behaviour of ram spermatozoa exposed to thermal shock. Ram spermatozoa freed from seminal plasma by a ‘swim-up’ procedure were submitted to thermal shock and fractionated by CCCD. Cell viability decreased from 68% to 18% after the treatment, showing a slight displacement of the cells from the right (where a higher enrichment of live cells is found) to the centre of the profile. A change of the distribution profile was shown in the presence of either ram or bull seminal plasma. Bull seminal plasma was able to move the profile to the right, whereas ram seminal plasma increased the proportion of cells with enhanced affinity for the lower dextran-rich phase. Plasma proteins isolated from both seminal plasmas moved the profile to the right. In addition, cell viability rose to 48% after the CCCD run in the presence of ram plasma proteins. This restoring effect was lost when ram plasma proteins were thermally denatured. Bovine serum albumin was not only unable to move the profile to the right but even promoted displacement of the profile to the left. This negative effect was also observed when proteins from bull seminal plasma were in the presence of protein-free ram seminal plasma. However, proteins isolated from ram seminal plasma still restored the profile in the presence of bull seminal plasma freed from proteins. The results presented here strongly suggest that seminal plasma proteins are absorbed by a spermatozoal surface previously exposed to thermic shock. These proteins would exert a highly specific protective effect on ram spermatozoa. In addition, in the ram seminal plasma there must be some factor which avoids this adsorption.     

Castration-induced hyperactivity of seminal vesicle in the catfish Clarias batrachus: a case of paradox and blockade by antiandrogen (cyproterone acetate) treatment

Castration of the catfish Clarias batrachus in late preparatory-early prespawning phase (April-May) caused time-dependent stimulatory effect on morphology, weight, and in the concentrations of biochemical correlates, such as total proteins, fructose, hexosamines and sialic acid in the seminal vesicle (SV). The peak changes were noticed on week 4 of castration. The hyperactivity was related to augmented production of testosterone by the SV of castrates with the levels significantly high from week 3 onwards. As a result, serum testosterone level fluctuated with a significant decrease in the first and fifth weeks, a significant increase in the third week, and no significant difference in the second and fourth weeks. Serum E2 level decreased significantly throughout. Cyproterone acetate treatment (CA; 1 mg/fish daily for 21 days) from the second day of castration decreased the size and weight of the SV and the concentrations of total proteins, hexosamines, fructose and sialic acid. The antiandrogen treatment did not alter serum testosterone level but the E2 level was significantly decreased. It is concluded that the hypersecretory activity of the SV in castrates is a sequel to local synthesis and action of testosterone and the effect could be prevented by CA by blocking androgen actions.     

Alteration of the anterior acrosome of motile bovine spermatozoa by fructose and hydrogen ion concentration

Storing cauda epididymal spermatozoa in seminal plasma or in defined media at 1 x 10(9) spermatozoa/ml for 24 h at 4 degrees C caused swelling of the apical ridge on motile spermatozoa (SAR) provided concentrations of fructose in the range normally found in seminal plasma or comparable levels of glucose were present. Evaluation of these conditions indicated that, with glycolysable sugars in the media, pH dropped from 6.6-6.7 to 5.7-6.0. Most of the pH decrease occurred during the first 2 h of slow cooling from 37 to 4 degrees C. pH decrease was undoubtedly due to sperm organic acid production which overwhelmed the relatively weak buffering capacity of the defined media and/or seminal plasma. Inducing pH decreases with HCl in fructose-free conditions, and using NaOH to prevent a pH decrease when fructose was included in media, demonstrated that exposing spermatozoa to pH values of 5.7-6.0 and not a specific response to fructose was the major cause of SAR.     

The effect of the sugar source on citric acid production by Aspergillus niger

Summary Under otherwise identical fermentation conditions, the sugar source has been shown to have a marked effect on citric acid production by Aspergillus niger. Sucrose was the most favourable source, followed by glucose and fructose and then lactose. No citric acid was produced from galactose. Strong relationships were observed between citric acid production and the activities of certain enzymes in myccelial cell-free extracts prepared from fermentation samples. When sucrose, glucose, or fructose was the sugar source pyruvate carboxylase activity was high, but 2-oxoglutarate dehydrogenase activity was not detected. When galactose was the sugar source pyruvate carboxylase activity was low, but 2-oxoglutarate dehydrogenase activity was high. It is suggested that whereas glucose and fructose repress 2-oxoglutarate dehydrogenase, thereby causing accumulation of citric acid, galactose does not. The activity of aconitase showed a direct relationship to the citric acid production rate. Thus, the activity was highest when sucrose was the sugar source, and lowest when galactose was the source. It is suggested that when large amounts of citric acid are lost from the cell the activity of aconitase increases as a response to the diminished intracellular supply of its substrate.     

Transaminases in cattle and buffalo (Bubalus bubalis) semen in relation to fertility and seminal characteristics during moderate and colder seasons

Semen from eight (four cattle and four buffalo) bulls was collected and analysed for physical characteristics and transaminase activity. The values of glutamic-oxaloacetic transaminase (GOT) and glutamic-pyruvic transaminase (GPT) activity were 1567±63 and 368±25 SF units¹ in the whole semen and 807±31 and 121±11 SF units in the seminal plasma for cattle and 1359±48 and 279±29 in the whole semen and 635±28 and 94±11 in the seminal plasma for buffalo. Cattle semen had significantly (P<0.01) higher mass motility, sperm concentration and transaminase activity than did buffalo semen. The enzyme activity was positively correlated with mass motility, sperm concentration and fertility, while only GOT activity was inversely related to the ambient temperature.     

Spermatozoal morphologies and fructose and citric acid concentrations in agouti (Dasyprocta leporina) semen

This study was conducted to identify the levels of fructose and citric acid, and sperm morphologies in agouti (Dasyprocta leporina) semen. These parameters may be important in identifying highly fertile semen from the agouti. The objectives were: (1) to investigate spermatozoal abnormalities in agouti semen and (2) to determine the concentrations of seminal fructose and citric acid in agouti semen samples. Semen samples were collected from 16 anaesthetised male agouti by electro-ejaculation. Fructose and citric acid concentrations were 256.86+/-63.54 mg/dl and 1877+/-147 mg/dl, respectively, measured with ELISA kits. Sperm morphologies, examined using eosin-negrosin staining, showed 11 morphologies. The most abundant (68.5%) sperm morphology (M1) showed no known sperm defects. Means for head, mid piece, tail and total length of the agouti spermatozoa was 5.23+/-0.04 microm, 5.18+/-0.08 microm, 37.52+/-0.24 microm and 47.96+/-0.25 microm, respectively for M1 sperm. The means of spermatozoa head and mid piece width and semen volume were 3.26+/-0.04 microm, 0.70+/-0.02 microm and 0.47+/-0.16 ml, respectively. It was concluded that as the fructose concentration in agouti ejaculate increased the percentage of spermatozoa with known spermatozoa defects increased (r=0.506; P<0.037; n=32). It is suggested that the M1 sperm could be the most competitive spermatozoa in agouti ejaculate. In conclusion standards for identifying fertile agouti semen were established.     

Effects of Losartan/Hydrochlorothiazide on Serum Uric Acid Levels and Blood Pressure in Hypertensive Patients

The effect of a mixed formulation of 50 mg losartan (LOS) and 12.5 mg hydrochlorothiazide (HCTZ) on blood pressure and the uric acid metabolism was analyzed in 73 patients who switched to this formulation from other antihypertensive drugs. Eight patients who switched to the formulation from the regular dose of renin-angiotensin (RA) inhibitor (angiotensin receptor blocker [ARB] or angiotensin-converting enzyme [ACE] inhibitor) only showed a significant decrease in blood pressure, from 156.9 ± 14.1/88.6 ± 9.7 mmHg to 128.3 ± 16.0/76.1 ±10.7 mmHg (p = 0.007), and a significant increase in serum uric acid levels, from 5.2 ± 1.1 mg/dL to 6.8 ± 0.7 mg/dL (p = 0.02). In the other 50 patients who switched from a combination of the regular dose of RA inhibitor and calcium channel blocker (CCB), their blood pressure significantly increased, from 126.0 ± 13.8/72.0 ± 10.0 mmHg to 132.5 ± 16.4/76.5 ± 11.3 mmHg (p = 0.02), and their serum uric acid levels also significantly increased, from 5.6 ± 1.1 mg/dL to 6.1 ± 1.3 mg/dL (p = 0.0002). Considering that guidelines recommend using antihypertensive therapies that do not lead to an increase in serum uric acid levels, we conclude that using the ARB/HCTZ combination is less suitable than the regular dose of the ARB/CCB combination due to its effect on hypertension and serum uric acid levels.     

Multiple effects of seminal plasma on the acrosome reaction of human sperm

Mammalian sperm do not respond to inducers of the acrosome reaction immediately after ejaculation. They become responsive after they are removed from seminal plasma and incubated in an appropriate medium. We tested the effects of seminal plasma on the development of acrosomal responsiveness. Washed human sperm incubated 24 hr in vitro with 10% (v/v) seminal plasma did not complete an acrosome reaction when exposed to human follicular fluid, progesterone, or ionomycin. Seminal plasma did not reduce sperm viability or motility. Electron microscopy of sperm incubated 24 hr with 5% seminal plasma and then treated with progesterone revealed no sign of membrane fusion or other changes that are associated with the acrosome reaction. During a 12-hr incubation, seminal plasma was 50% effective at inhibiting the acrosomal response to progesterone when diluted 821 ± 112 foid (mean ±SD, n = 3). Sperm that were incubated with seminal plasma for 24 hr and then washed free of the seminal plasma became acrosomally responsive over the following 24 hr, at a rate similar to that of sperm not incubated with seminal plasma in vitro. When sperm were incubated 6 hr without seminal plasma and then seminal plasma was added, the sperm population transiently became more responsive to progesterone, and then became unresponsive. During incubation in vitro, the ability of sperm to have an augmented response to a mixture of seminal plasma plus progesterone developed slightly earlier and more rapidly than ability to respond to progesterone alone. When sperm were incubated 24 hr without seminal plasma, a few acrosome reacted in response to the addition of seminal plasma alone. Therefore, depending on how it is applied, seminal plasma can prevent or reverse the development of acrosomal responsiveness, and it can enhance or induce the acrosome reaction. © 1993 Wiley-Liss, Inc.