Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P56851 (epididymal)
 11,273 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have attempted to measure net changes in lipid content in a discrete "intermuscular" fat pad during rapid lipogenic activation that occurs after a previously fasted mouse nibbles a glucose-rich test meal for several minutes. The popliteal fat pad was chosen for the study since it has been shown to be about an order of magnitude more active than the epididymal fat pad in the synthesis of fatty acids from glucose carbon in fasted-refed mice. We found a highly reproducible net loss in the popliteal fat pad's weight and lipid content during fasting. Net deposition of lipid occurred when 24-h fasted mice were allowed to eat a fat-free, 58% glucose diet for several minutes. In two out of three experiments lipid repletion was complete after one brief period of nibbling. Significant decreases in the net amounts of each majority fatty acid, 16:0, 16: 1, 18:1 and 18:2, were found to occur in the popliteal fat pad during a 24-h fast. After nibbling their test meal for several minutes, previously fasted mice restored their major essential fatty acid, linoleic acid, to the original fed level within 2 h, even though total lipid repletion was incomplete. Highly significant net increases in each major non-essential fatty acid were also found after brief ingestion of the test meal; however, in one experiment (incomplete repletion) only about half of the depleted fatty acids was restored. When two successive glucose test meals were eaten (2-h interval), popliteal fat converted glucose carbon to fatty acids more than twice as fast after the second feeding as after the first. However, no significant additional increment either in tissue weight or in total lipid fatty acids was found after the second test meal. Based on these findings, the possible significance of intermuscular fat in the utilization and deposition of fat is discussed.
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PMID:Net changes in intermuscular fat before and during rapid lipogenic activation in mice. 93 52

Fasting has been reported to quantitatively increase linoleic and arachidonic acids in liver triacylglycerols, but the origin and mechanism of this change are unknown. The changes in long-chain fatty acids and triacylglycerol species of liver, serum, adipose tissue, and heart were therefore examined during a period of 24- or 48-h fasting in the rat. In liver and serum triacylglycerols, fasting resulted in a quantitative increase in arachidonic, stearic, linoleic, alpha-linolenic, and docosahexaenoic acids but a decrease in oleic, palmitic, and palmitoleic acids. After fasting, oleic acid was depleted the most from liver and serum triacylglycerols followed by palmitoleic and palmitic acids. Triacylglycerol species containing palmitic, palmitoleic, and oleic acids were depleted the most from liver and serum during fasting. Linoleic acid-enriched triacylglycerol species were proportionally and, in some cases, quantitatively increased in liver and serum triacylglycerols during fasting. Net retention of triacylglycerol species with a total acyl carbon number of 56 or 58 in the liver and 60 in serum was also observed during fasting. Selective retention of triacylglycerol species did not occur in the heart or perirenal or epididymal adipose tissue during fasting. Tissue phospholipid fatty acids were largely unaffected by fasting. Our data suggest that during fasting, long-chain fatty acids released from adipose tissue are differentially utilized and hepatic triacylglycerol species are remodeled, permitting optimal tissue composition of essential fatty acids, particularly linoleic acid.
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PMID:Preferential retention of linoleic acid-enriched triacylglycerols in liver and serum during fasting. 151 Jan 64

Proluminal movement of 3H-testosterone and 3H-sucrose from peritubular to intratubular fluids of the adult rat testis and epididymis was investigated by using in vivo microperifusion and subsequent micropuncture of seminiferous tubules and caput, corpus, and cauda epididymal tubules. Tubules were perifused with Minimum Essential Medium containing 3H-testosterone or 3H-sucrose. 14C-polyethyleneglycol was included in the perifusion fluid as a marker for contamination of intraluminal fluid by interstitial fluid. Radioactivity of isotopes in perifusion and intraluminal fluids was determined at one and two hours after perifusion and the percentage of peritubular isotopes appearing in intraluminal fluid was determined. Net entry of 3H-sucrose into the seminiferous and epididymal tubules was significantly reduced. Proluminal movement of 3H-androgen across the seminiferous epithelium was also restricted. In contrast, intraluminal 3H-androgen concentrations in caput epididymal fluid were 200 to 300% of those in peritubular fluid at both one and two hours after perifusion. Similar results were found in the corpus epididymidis. 3H-androgen concentrations in cauda epididymal fluid were approximately 125% of peritubular isotope concentrations. The exact mechanism underlying this uphill proluminal movement of 3H-androgen into the rat epididymal lumen remains to be elucidated.
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PMID:Transepithelial movement of non-polar and polar compounds in male rat reproductive tubule examined by in vivo microperifusion and in vivo micropuncture. 231 22

Rete testis fluid (RTF) and luminal fluid collected by micropuncture at selected epididymal sites were analyzed to characterize the spectrum of proteins and to quantify the net gain or loss of total/bulk protein and androgen-binding protein (ABP) between successive regions within the ductus epididymidis. Based on one-dimensional SDS gel electrophoresis, the spectra of proteins in RTF and fluids from the proximal, central, and distal caput through proximal corpus epididymidis differed from each other. Concentrations of sperm, bulk protein, and ABP increased from the rete testis through the central caput epididymidis. Electron microscopic studies following intraluminal microinjections of RTF proteins conjugated to colloidal gold at specific sites in the excurrent ducts revealed that 145 times more protein-gold was endocytosed in the ductuli efferentes than in any of the four regions of the caput epididymidis. Thus, ductuli efferentes were the major extra-testicular site of endocytosis of bulk protein present in RTF; at least a portion of the uptake was specific. On a per sperm basis, the amount of protein present in the central caput epididymidis was less than 15% of that leaving the testis. Although most of the protein present in RTF (greater than or equal to 86 mg/d) must be absorbed in the ductuli efferentes and the initial segment of the epididymis and replaced by newly secreted proteins (greater than or equal to 34 mg/d), there was negligible loss of ABP in these regions. Net loss of ABP occurred primarily in the distal caput and proximal corpus epididymidis. These studies demonstrate that ABP is spared from endocytosis along with the bulk protein in RTF and conserved for functions in epididymal regions far distal to the site of bulk protein loss.
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PMID:Proteins in luminal fluid of the ram excurrent ducts: changes in composition and evidence for differential endocytosis. 232 1

Stress is believed to influence male reproductive activity. Male rats were subjected to immobilization stress for 2 h/day for 30 days to assess the effects of stress on testicular function. Net mass of the testes, epididymes and the seminal vesicles, sperm morphology, number of epididymal sperms and percent progressive motility of the sperms were determined. Adrenal weights were significantly increased (P less than 0.05) in the stressed animals. There was no significant difference between the control and the stressed animals with respect to testicular and epididymal weight, level of sperm production, progressive motility, seminal vesicular weight and abnormal forms. Histological examination also revealed a similarity in the structure of seminiferous tubules, adequacy of cell types of developing germ cells, structure of Leydig cells and epididymal lumina in both the groups. This study demonstrated a lack of significant effect of immobilization stress on testicular function in rats.
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PMID:Testicular function in rats following immobilization stress. 289 9

Male Sprague-Dawley rats were exposed for 8 h to continuous-wave microwave radiation (MWR, 1.3 Ghz) at a mean specific absorbed dose rate of 9 mW/g. MWR exposure and sham-irradiation took place in unidirectionally energized cylindrical waveguide sections, within which the animals were essentially unrestrained. The MWR treatment in this setting was determined to yield an elevation of deep rectal temperature to 4.5 degrees C. The animals were taken for analysis at 6.5, 13, 26, and 52 days following treatment, which corresponded to .5, 1, 2, and 4 cycles of the seminiferous epithelium. Net mass of testes, epididymides, and seminal vesicles; daily sperm production (DSP) per testis and per gram of testis; and the number of epididymal sperm were determined. The levels of circulating follicle-stimulating hormone (FSH) and leutinizing hormone (LH) were derived via radioimmunoassay of plasma samples taken at the time of sacrifice. Despite the evident acute thermogenesis of the MWR at 9 mW/g, no substantial decrement in testicular function was found. We conclude that, in the unrestrained rat, whole body irradiation at 9 mW/g, while sufficient to induce evident hyperthermia, is not a sufficient condition for disruption of any of these key measures of testicular function.
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PMID:Acute, whole-body microwave exposure and testicular function of rats. 357 98

The transport of proteins across continuous capillary endothelium is believed to be mediated by micropinocytic vesicles which shuttle molecules between the lumenal and abluminal plasma membrane. We have studied the ability of capillary endothelial cells isolated from rat epididymal fat to endocytose fluorescently labelled ovalbumin within micropinocytic vesicles. Net association of fluorescent ovalbumin with endothelial cells reaches an equilibrium after 40 minutes of incubation. This equilibrium is presumably due to a balance between endocytosis and subsequent exocytosis of this protein. Capillaries equilibrated with fluorescent ovalbumin exhibited rapid exocytosis of this protein when it was removed from the external medium. The rate of endocytosis was concentration dependent and obeyed the kinetics expected for adsorptive phase endocytosis. High concentrations of ovalbumin stimulated the ingestion of 14C-sucrose, a marker of fluid endocytosis, suggesting that protein can affect the movement of vesicles within the endothelial cytoplasm. These results imply that capillary endothelium isolated from rat epididymal fat exhibits the ability to endocytose and subsequently exocytose protein. This demonstrates that the two components of endothelial vesicular transport or transcytosis can be observed and studied in a system of isolated capillary endothelium.
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PMID:Endocytosis and exocytosis of protein in capillary endothelium. 643 Sep 19

Male Sprague-Dawley rats were exposed for 6 h per day for nine days to pulse-modulated microwave radiation (1.3 GHz, at 1-microseconds pulse width, 600 pulses per second). Exposures were carried out in cylindrical waveguide sections at a mean dose rate of 6.3 mW/g; sham controls were treated similarly and received no irradiation. At time periods corresponding to 0.5, 1.0, 2.0, and 4.0 cycles of the seminiferous epithelium, groups of four sham-irradiated and four irradiated rats were killed and the testes removed for analysis. Net mass of the testes, epididymides, and seminal vesicles; daily sperm production (DSP) per testis and per gram of testis; sperm morphology; and the number of epididymal sperm were determined. There were no statistically significant differences between the sham-irradiated and irradiated groups with respect to any measured variable. In a group of seven surrogate animals of similar body mass, the dose rate of 6.3 mW/g caused a net change in body temperature (via rectal probe) of 1.5 degrees C.
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PMID:Testicular function of rats following exposure to microwave radiation. 687 Sep 65

The investigation demonstrated a restriction of [3H]3-O-methyl-D-glucose ([3H]3-OMG) net transport into seminiferous tubule fluid. Net transport of [3H]3-OMG into the cauda epididymidal tubule was even more limited. By 4 months after vasectomy, there was no statistical difference in the net transport of the isotope into the seminiferous tubule fluid, but there was a significant increase in net transport into cauda epididymidal fluid. These results demonstrate that the blood-epididymal barrier can be even more restrictive to molecular transport than the blood-testis barrier and that vasectomy can have subtle effects on characteristics of molecular transport in the cauda epididymidis.
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PMID:[3H]3-O-methyl-D-glucose transport from blood into the lumina of the seminiferous and epididymal tubules in intact and vasectomized hamsters. 743 37

The present study was undertaken to determine whether or not antigrade, proluminal 3H-androgen movement in the caput epididymis occurs in the absence of native lumen content. A single tubule was perfused with artificial caput fluid containing no androgen-binding protein for 30 min and subsequently tubules were perifused with Minimum Essential Medium perifusion fluid containing 26.7 microCi/ml 3H-testosterone and 1.3 microCi/ml 14C-polyethyleneglycol for 1 h. Radioactivity of isotopes in perifusion and intraluminal fluids was determined at 1 h after sustaining perifusion, and the percentage of peritubular isotopes appearing in the intraluminal fluid was determined. Net entry of 3H-androgen into the epididymal tubules in the presence of native intraluminal content was approximately 323%. In contrast, intraluminal 3H-androgen concentrations in the epididymal fluid in the absence of native lumen content were significantly reduced, to 100% of those in the peritubular fluid. Antigrade, proluminal movement of 3H-androgen in the caput epididymis does not occur in the absence of native lumen content. Androgen-binding protein in the epididymal lumen may be required to maintain uphill proluminal movement of 3H-androgen into the tubules.
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PMID:Intraluminal content is required for the maintenance of antigrade proluminal movement of 3H-androgens into rat caput epididymal tubules. 789 65


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