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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The sensitivity of the CellSoft computer-assisted sperm analysis (CASA) system to detect changes in rat sperm motion was evaluated. CASA motion endpoints were measured in cauda epididymal sperm from Long-Evans rats treated with each of three known male reproductive toxicants reported to affect the epididymis and epididymal sperm motility: alpha-chlorohydrin, ornidazole, and trimethylphosphate. Significant changes in endpoints describing sperm swimming vigor (curvilinear velocity and straight-line velocity) and pattern (linearity and amplitude of lateral head displacement) were observed for rats dosed with each agent when evaluations included mean values and other statistical parameters (i.e., percentiles and distributional shape). alpha-Chlorohydrin (ACH) treatment (10 mg/kg/day; 8 days) resulted in reductions in the mean percentage of motile sperm, curvilinear velocity (VCL), straight-line velocity (VSL), lateral head displacement (ALH), and linearity (LIN). Treatment with ornidazole (ONZ) (200 mg/kg/day/14 days) reduced the percentage of motile sperm. Mean VCL, VSL, and ALH were reduced by 400 mg ONZ/kg/day treatment. Trimethylphosphate (TMP) treatment led to (a) a reduction in the 75th and 90th percentiles for ALH (100 mg TMP/kg/day; 5 days) (P < or = 0.04), (b) a reduction in VCL, VSL, and ALH (250 mg TMP/kg/day), (c) a reduction in the percentage of motile cells and in the 10th and 25th percentiles for VSL (600 mg TMP/kg/day), and (d) increases in the 90th percentile for VSL, in the mean, 75th, and 90th percentiles for VCL, and in the 75th and 90th percentiles for ALH (600 mg TMP/kg/day). The general utility of these analytic approaches in reproductive toxicology studies was demonstrated in the observations of effects at or below dose levels previously reported.
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PMID:Effects of three male reproductive toxicants on rat cauda epididymal sperm motion. 128 60

Random and nonrandom factors associated with sample preparation and the automated analysis (CellSoft) of rat cauda epididymal sperm motion were studied. Random factors included inherent system variation at both the individual cell level and at the multiple cell level. Repeated analyses of identical tracks across grey level revealed a statistical interaction between grey settings and curvilinear velocity. However, in multiple track analyses, grey level was seen to be a factor only at higher settings. Nonrandom factors included time after sample preparation, dilution medium, and sample preparation procedures. Using a nicked preparation of the entire cauda epididymis from Long-Evans rats, the effects of time were studied on sperm suspended in 1) phosphate-buffered saline + 10 mg BSA/mL, 2) TEST yolk buffer, and 3) Medium 199. In PBS/BSA, the percent motile sperm estimate decreased (50% to 30%) over an hour, while the curvilinear velocity increased (127 to 142 microns/sec). Both sperm motion parameters were maintained in the TEST yolk buffer and in the Medium 199, although at lower values for the latter. Evaluation of the relative contribution of several factors, nested within sample, to the overall variance of three separate motion endpoints revealed that there was a large variation from field to field, negligible variation between overall CellSoft analyses of 200 cells or more, low variation at the preparation aliquot level, and moderate variation at the animal level. In planning experiments to test for effects on sperm motion endpoints, consideration of the relative contribution of the individual study factors to the overall variance of the parameter estimates will result in more sensitive experimental designs.
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PMID:Sources of variation in the computer-assisted motion analysis of rat epididymal sperm. 181 May 76

Researchers from the University of Missouri and the German Cancer Research Center compared sperm characteristics and sexual behavior of 32 150-day old Long Evans male rats who received doses of either 0, 5, 10, or 20 mg gossypol/kg body weight to learn motivation in seeking sexual contact with a receptive female and copulatory effectiveness in relation to epididymal sperm reserves and endocrine target tissues. Females included gonadally intact and ovariectomized rats. Even though none of the male rates experienced azoospermia after 11 weeks of receiving gossypol, significant reductions in sperm concentrations and motility occurred for those receiving 10-20 mg/kg body weight (p.01) indicating possible infertility. No changes in reproductive physiology (weight of sex organs) and sexual performance occurred between the control rats and those receiving 5 mg gossypol, but changes did occur between the control rats and both those receiving 10 and 20 mg gossypol. Sexual motivation fell as the dosage of gossypol increased. In fact, the interaction of amount and duration affected suppression. The gradual suppression of serum testosterone may have been responsible for the decline in libido. These results suggest that gossypol may indeed cause sterility, but also may reduce the libido. In addition, they show that sexual performance and motivation can differ independently.
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PMID:Search for a male contraceptive: the effect of gossypol on sexual motivation and epididymal sperm. 207 49

The automated analysis of sperm motion endpoints is potentially useful in identifying male reproductive toxicants and ultimately in predicting fertility in humans. The present study was designed to evaluate the automated analysis of rat sperm motility characteristics following subchronic administration of epichlorohydrin. This type of validation is a prerequisite for inclusion of sperm motion measurements in the process of reproductive risk assessment. In the present studies videotapes were made of cauda epididymal spermatozoa from Long-Evans rats, both untreated and treated with epichlorohydrin. From analysis of videotapes of control epididymal spermatozoa, the relationship of various sperm motion endpoints and settings of the CellSoft computer-assisted sperm motion analysis system (Cryo Resources, Ltd., New York, NY) is described. Optimal settings of the system for analysis of rat spermatozoa are detailed. Employing data from both control and epichlorohydrin-treated animals, a statistical methodology is described that evaluates: (1) the distributions of CellSoft generated sperm motion endpoints, (2) the correlations between these endpoints, and (3) techniques for detection of dose-related effects.
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PMID:The automated analysis of rat sperm motility following subchronic epichlorohydrin administration: methodologic and statistical considerations. 259 69

Male and female Long-Evans rats were treated with epichlorohydrin (ECH) by oral gavage (males: 12.5, 25, and 50 mg/kg/day; females: 25, 50, and 100 mg/kg/day) for 21 and 14 days, respectively, prior to mating trials with untreated animals. Treated females were further dosed until delivery. Fertility was assayed in the high-dose males only and was found to be totally impaired. No measured parameters of female reproduction were changed relative to controls. Treated males showed normal copulatory behavior. Sperm morphology and percentage motile sperm were not statistically different from control values in both ejaculated and cauda epididymal samples from ECH-treated animals. The number of sperm in ejaculates was normal while cauda epididymal sperm count was slightly decreased in males at the 50 mg ECH/kg dose level. Mean curvilinear velocity, straight-line velocity, and amplitude of lateral head displacement of cauda epididymal sperm were significantly reduced by ECH at 12.5 mg/kg/day and above. Sperm track linearity was also reduced, but only at 50 mg/kg/day. Beat/cross frequency of sperm was significantly increased at 12.5 mg/kg/day and above. All of the above sperm motion parameters showed dose-dependent trends. These effects are consistent with the spermatozoal metabolic lesions reported for alpha-chlorohydrin, a metabolite of ECH.
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PMID:Effects of epichlorohydrin on male and female reproduction in Long-Evans rats. 276 56

Groups of male Long-Evans rats 30, 50, or 70 d old were injected subcutaneously (sc) with a single dose of 0, 5.5, 11.5, or 24.6 mumol Cd/kg as cadmium chloride. All animals were killed 60 d after treatment. At 2 h prior to sacrifice, the rats were injected sc with 100 IU human chorionic gonadotrophin (hCG) to maximally stimulate serum testosterone concentrations. After sacrifice the testes, epididymides and seminal vesicles were removed and weighed. Cardiac blood was taken, and serum concentrations of testosterone (sT) and follicle-stimulating hormone (sFSH) were determined. Sperm concentration in luminal fluid collected from the vas deferens was determined. Significant (p less than 0.01) dose-dependent effects for all measured reproductive parameters were noted in the 70-d-old animals, while no effects were seen in the 30- or 50-d-old rats in either seminal vesicles weight or hCG-stimulated sT concentration. In the absence of significant (p greater than 0.05) changes in body weight gain, effects were seen in testes and epididymides weight, sperm concentration, and sFSH in the 70-d-old rats at Cd doses that were lower than those necessary to bring about similar changes in the 30- or 50-d-old animals. The sensitive indicators of Cd exposure in all age groups were testicular weight greater than epididymal weight greater than vas deferens sperm concentration greater than sFSH concentration. Seminal vesicle weight and sT concentration were found to be the least sensitive. Regression analyses indicated a significant interaction of age with dose; the 70-d-old rats required 30-61% less Cd/kg to cause a 50% change in a measured parameter than did the 30-d-old animals, while the 50-d-old rats required 15-47% less.
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PMID:Age-related dose response of selected reproductive parameters to acute cadmium chloride exposure in the male Long-Evans rat. 309 56

Male Long-Evans rat pups were either fed by continuous intragastric infusion of a milk formula to match the growth rate of their normally reared siblings, or overfed by continuous infusion of a fat-supplemented formula from d 4 through d 18 postpartum. The early overfeeding accelerated growth and the overfed rats remained significantly heavier than normally reared siblings as adults. Early overfeeding with this procedure led to an adult obesity at 14 mo characterized by significantly larger epididymal and retroperitoneal fat depots resulting from an increase of both fat cell size and number, and by an increase in adipose tissue lipoprotein lipase activity. Gastrostomy rearing per se, without overfeeding, resulted in adult rats that weighed the same as normally reared siblings but had significantly larger retroperitoneal fat depots because of more adipocytes. These findings suggest that the quantity of food consumed during early growth and development, and the quality of early nutrition and/or the early rearing environment affect adipose tissue development and have long-term consequences that persist in the rat.
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PMID:Long-term effects on adiposity after preweaning nutritional manipulations in the gastrostomy-reared rat. 311 35

1. Groups of male Long Evans rats were sacrificed at the ages of 10, 16, 20, 24, 28, 32, 38 and 45 weeks. 2. The two epididymal fat pads from each rat in each group (4-5 rats) were excised for the preparation of adipocytes. 3. Cell suspensions were incubated in triplicate with each of seven norepinephrine concentrations ranging from 0.5694 to 569,400 nM. 4. Lipolytic responses are expressed as nmol glycerol released/microgram DNA/90 min. 5. The animals reached a peak response between the ages of 20 and 32 weeks. 6. Aging resulted in a gradual increase in the apparent affinity (Km) of the response yielding system for norepinephrine. 7. Initially an increase in the lipolytic capacity of the cells in response to norepinephrine, is observed, as reflected by the Vmax values up to an age of 20 weeks. 8. Vmax then stays relatively constant at elevated levels up to an age of 32 weeks, followed by an abrupt decrease with further aging.
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PMID:Age-related norepinephrine induced lipolytic response of isolated rat adipocytes. 336 97

Electrophysiological measurements were made on endothelial cells initially isolated as individual clones from bovine brain microvessels, and then grown as monolayers on a permeable support of glutaraldehyde-treated collagen gel. When transendothelial cell resistance (R) of the clones was measured, there was a range of values from a low of 157.4 +/- 4.5 omega.cm2 (n = 6) to a high of 783.2 +/- 7.0 omega.cm2 (n = 34). With the high-resistance cells, there was also a small potential difference of -0.46 +/- 0.03 mV luminal-side negative (n = 34). In comparison, endothelial cells from bovine aortas and rat epididymal fat pads cultured on the collagen gels had transendothelial R values of 13.5 +/- 0.2 (n = 62) and 0.45 +/- 0.03 (n = 10) omega.cm2, respectively. Exposure of the high-resistance brain endothelial cell monolayers to a Ca2+-free medium for 10 min decreased the R to 75% of the control values. Addition of Ca2+ back to the medium caused a return of the transendothelial R to control values within 1 h. Endothelial cells were also grown to confluency on microcarrier beads for permeability measurements to Evans blue dye-bovine serum albumin. Microcarriers with no cells (control) and microcarriers with bovine and epididymal endothelial cell monolayers showed no difference in the amount of adsorbed dye. Microcarriers with brain endothelial monolayers excluded up to 80% of the dye. This mammalian brain endothelial culture system will be a useful model for studies of the electrophysiological and permeability properties of the blood-brain barrier.
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PMID:Electrical resistance and macromolecular permeability of brain endothelial monolayer cultures. 342 32

Current test strategies for assessing male reproductive toxicity may be inadequate for estimating risk in humans. High levels of sperm production and existence of large epididymal sperm reserves in most test species may impede the detection of spermatotoxicity at low doses. The current report reflects initial efforts to address these issues. An active schedule of copulation was employed to reduce cauda epididymal reserves in the rat. The detection of spermatotoxicity in this animal relative to its nonmated counterpart was then compared following exposure to ethoxyethanol (EE). Adult, male Long-Evans hooded rats were assigned to a "mate" or "nonmate" condition, with the former mated every other day (3-hr sessions) for 2 weeks prior to and then throughout the experiment. After 2 weeks, males from each group were randomly assigned to receive either 0, 150, or 300 mg/kg (po) of EE, 5 days/week for 6 weeks. Males were then sacrificed and organ weights, testicular spermatid counts, and cauda epididymal sperm count and sperm morphology were obtained. EE produced a significant reduction in testicular weight and spermatid counts in mated and nonmated animals receiving 300 mg/kg. Significant decreases were also noted in epididymal sperm count and percentage normal morphology. However, these effects were seen in the nonmated animals only at 300 mg/kg, whereas significant reductions in both parameters were also obtained at 150 mg/kg in the males mated bidaily. The data from this study suggest that bidaily matings, by reducing epididymal sperm reserves, can enhance the detection of spermatotoxicity.
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PMID:Decreasing epididymal sperm reserves enhances the detection of ethoxyethanol-induced spermatotoxicity. 375 52


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