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)

Inhibin was localized in the ovine testis, excurrent ducts, and accessory sex glands by using a rabbit antiserum against a synthetic polypeptide representing the first 30 amino acids of porcine inhibin alpha-subunit. Concentrations of inhibin in fluids entering and leaving the epididymis also were determined in a radioimmunoassay using the same antibody. In the testis, immunostaining of inhibin was conspicuous in the seminiferous epithelium. Leydig cells occasionally were stained and the tunica media of blood vessels always was stained. Intense staining was observed in the epithelia lining the rete testis and ductuli efferentes. Staining also was intense in the epithelium of the initial segment and proximal caput epididymidis, and became less intense along the length of the epididymis. These observations were consistent with concentrations of inhibin in rete testis fluid (8.2 pmol/ml) entering the ductuli efferentes and in cauda epididymal plasma (0.67 pmol/ml) leaving the epididymis. Epithelia of ampullary and vesicular glands and of some prostatic acini were positively stained, but bulbourethral glands were never stained. Adrenal cortex, some proximal convoluted tubules in the kidney, and transitional epithelium of the urethra also were stained. Based on radioimmunoassay data and fluid flow rates for the ram, it was concluded that almost all of the 328 pmol inhibin that enters the ductuli efferentes daily is endocytosed in the proximal parts of the excurrent duct system. The physiological role(s) for inhibin, or inhibin-like peptides, in the excurrent duct system remains speculative.
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PMID:Immunolocalization and concentrations of inhibin alpha in the ovine testis and excurrent duct system. 259 Jul 16

Adrenaline, an alpha and beta adrenergic agonist don't modify theophylline induced lipolysis in perirenal and epididymal adipose tissue of the rabbit. Clonidine an alpha 2 adrenergic agonist inhibits theophylline stimulated lipolysis in the two tissue indicating the existence of alpha 2 adrenergic responsiveness. Direct identification of these receptors by radioligand binding studies shows that (H3) yohimbine an alpha 2 adrenergic antagonist binds to rabbit's fat cell membranes with high affinity: KD = 1.7 +/- 0.1 nmoles. The maximal number of binding sites at saturation is low 16 +/- 29 fmoles/mg protein.
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PMID:[Identification of alpha-2 adrenergic receptors in rabbit adipocytes]. 285 61

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

Intracellular pH (pHi) of primary monolayer cultures of the rat epididymal cells has been measured using fluorescent dye 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein (BCECF). When incubated in normal Krebs-Henseleit (K-H) solution containing 25 mM HCO3, cell monolayers exhibited a basal pHi of 7.17 +/- 0.08. Amiloride (0.5 mM) added to the cell monolayers caused an immediate and sustained fall in pHi by 0.43 +/- 0.05 pH unit. Similar effects were produced when extracellular Na ions were substituted by N-methyl-D-glucamine. Addition of SITS (0.5 mM) or DPC (0.6 mM) resulted in a transient intracellular alkalosis. Adrenaline (0.23 microM) caused a fall in pHi by 0.33 +/- 0.05 pH unit. The fall was slow and was achieved after 30 min (half time 9.9 min). The effect of adrenaline was reversible upon washing and was blocked by propranolol (2 microM). The effect of adrenaline was mimicked by forskolin (10 microM) and Br-cAMP (0.5 mM) which caused a fall in pHi by 0.35 +/- 0.03 and 0.35 +/- 0.02 pH unit respectively. Addition of diphenylamine-2-carboxylate (DPC, 0.6 mM) to the cuvette completely blocked the intracellular acidification produced by adrenaline or forskolin. However, addition of SITS (0.5 mM) did not prevent the intracellular acidosis induced by these agonists. If monolayers were first treated with forskolin (10 microM), the intracellular pH fell, when stabilized, subsequent addition of amiloride caused a further fall in pHi. When incubated in a Cl-free solution (Cl substituted by gluconate), cell monolayers exhibited a pHi of 7.23 +/- 0.07 (values not significantly different from monolayers incubated in HCO3 solution).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Intracellular pH measurement in primary monolayer cultures of rat epididymal cells. 292 94

1. Acetyl-CoA carboxylase activity was measured in extracts of rat epididymal fat-pads either on preparation of the extracts (initial activity) or after incubation of the extracts with citrate (total activity). In the presence of glucose or fructose, brief exposure of pads to insulin increased the initial activity of acetyl-CoA carboxylase; no increase occurred in the absence of substrate. Adrenaline in the presence of glucose and insulin decreased the initial activity. None of these treatments led to a substantial change in the total activity of acetyl-CoA carboxylase. A large decrease in the initial activity of acetyl-CoA carboxylase also occurred with fat-pads obtained from rats that had been starved for 36h although the total activity was little changed by this treatment. 2. Conditions of high-speed centrifugation were found which appear to permit the separation of the polymeric and protomeric forms of the enzyme in fat-pad extracts. After the exposure of the fat-pads to insulin (in the presence of glucose), the proportion of the enzyme in the polymeric form was increased, whereas exposure to adrenaline (in the presence of glucose and insulin) led to a decrease in enzyme activity. 3. These changes are consistent with a role of citrate (as activator) or fatty acyl-CoA thioesters (as inhibitors) in the regulation of the enzyme by insulin and adrenaline; no evidence that the effects of these hormones involve phosphorylation or dephosphorylation of the enzyme could be found. 4. Changes in the whole tissue concentration of citrate and fatty acyl-CoA thioesters were compared with changes in the initial activity of acetyl-CoA carboxylase under a variety of conditions of incubation. No correlation between the citrate concentration and the initial enzyme activity was evident under any condition studied. Except in fat-pads which were exposed to insulin there was little inverse correlation between the concentration in the tissue of fatty acyl-CoA thioesters and the initial activity of acetyl-CoA carboxylase. 5. It is suggested that changes in the concentration of free fatty acyl-CoA thioesters (which may not be reflected in whole tissue concentrations of these metabolites) may be important in the regulation of the activity of acetyl-CoA carboxylase. The possibility is discussed that the concentration of free fatty acyl-CoA thioesters may be controlled by binding to a specific protein with properties similar to albumin.
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PMID:Hormonal regulation of adipose-tissue acetyl-Coenzyme A carboxylase by changes in the polymeric state of the enzyme. The role of long-chain fatty acyl-Coenzyme A thioesters and citrate. 415 93

1. Experiments were conducted to compare the abilities of epididymal adipocytes from mice selected for growth (line G) and from unselected mice (line C) to: (a) incorporate glucose, (b) respond to insulin, and (c) mobilize lipids, and to relate these abilities to the food intake of the donors.2. During the 3-week pre-experimental period, line G mice gained body weight 78% faster and ate 35% more food than line C mice; both lines had similar intakes per unit of metabolic body size.3. Line G epididymal fat pads weighed 227% more than those of line C and contained adipocytes which were 38% larger; it was estimated that they contained approximately 65% more cells.4. The basal rate of glucose incorporated into lipids (per unit protein) was highest in line C adipocytes, whereas the basal rates of glucose oxidation to CO(2) and the total glucose incorporation (uptake) were similar for adipocytes from both lines.5. Insulin (1000 muu./ml.) caused adipocytes from both lines of mice to increase significantly the incorporation of glucose into CO(2) and lipids; the largest elevation occurred when the incubation medium contained 0.1 mg glucose/ml. At this concentration of glucose, the minimum effective dose (MED) of insulin to produce a significant increase in glucose oxidation was similar for both lines. However, the MED of insulin necessary to significantly increase glucose incorporation into lipids and into the sum of CO(2) and lipids was highest in the larger, line G adipocytes. Furthermore, the magnitude of the insulin-induced increase in glucose incorporation was much less for line G than for the line C adipocytes.6. Epinephrine significantly elevated the rates of NEFA and glycerol release and NEFA re-esterification. The highest rates of NEFA and glycerol release occurred in line C adipocytes, whereas the highest rate of NEFA re-esterification occurred in the line G adipocytes.7. Glucose had no effect on NEFA release but significantly elevated the rates of glycerol release (in most instances) and NEFA re-esterification.8. The larger number of adipocytes in line-G adipose tissue allows for more total incorporation of glucose and a greater overall release of glycerol by this tissue. Consequently, a greater reduction of glucose concentration and a larger elevation of glycerol concentration in the blood can occur; either of these could be the feed-back signal which resulted in the larger long-term food intake by the line G mice.
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PMID:Glucose metabolism and lipid mobilization by adipocytes from mice selected for growth. 441 83

The release of S-100 protein from epididymal fat pads was enhanced by epinephrine in vitro, and about 50% of S-100 protein in the tissue was released into the medium after 2-h incubation at 37 degrees C with 10 microM epinephrine. Similar results were obtained with the incubation of isolated adipocytes. The S-100 protein release was also enhanced by isoproterenol, norepinephrine, ACTH, and dibutyryl cyclic AMP, which all increase the lipolysis by increasing cyclic AMP levels in the tissue. Propranolol, a beta-adrenergic blocker, could block the increase of S-100 protein release by catecholamines, indicating that the release was mediated by the beta-adrenergic effect of catecholamines. However propranolol had no suppressive effect on the enhancement of S-100 protein release by ACTH or dibutyryl cyclic AMP. Insulin had an inhibitory effect on the epinephrine-enhanced S-100 protein release. Epinephrine or ACTH could not stimulate the S-100 protein release in the absence of Ca2+, whereas the epinephrine-enhanced glycerol release was not affected under the same conditions. The increase in S-100 protein release was induced by only a pretreatment of the tissue with epinephrine. However, the lipolysis in the tissue was not enhanced by the pretreatment alone. These results indicate that the release of S-100 protein from adipocytes is regulated by the hormones that have been known to control the lipolysis with a manner slightly different from that of lipolysis.
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PMID:Hormonal regulation of adipose S-100 protein release. 609 38

1. Adipocytes isolated from epididymal fat-pads of fed rats were incubated with different concentrations of glucagon, insulin, adrenaline and adenosine deaminase, and the effects of these agents on the ;initial' activity of acetyl-CoA carboxylase in the cells were studied. 2. Glucagon (at concentrations between 0.1 and 10nm) inhibited acetyl-CoA carboxylase activity. Maximal inhibition was approx. 70% of the ;control' activity in the absence of added hormone, and the concentration of hormone required for half-maximal inhibition was 0.3-0.5nm-glucagon. 3. Incubation of cells with adenosine deaminase resulted in a similar inhibition of acetyl-CoA carboxylase activity. Preincubation of adipocytes with adenosine deaminase did not alter either the sensitivity of carboxylase activity to increasing concentrations of glucagon or the maximal extent of inhibition. 4. Adrenaline inhibited acetyl-CoA carboxylase to the same extent as glucagon. Preincubation of the cells with glucagon did not alter the sensitivity of enzyme activity to adrenaline or the degree of maximal inhibition. 5. Insulin activated the enzyme by 70-80% of ;control' activity. Preincubation of the cells with glucagon did not alter the concentration of insulin required to produce half the maximal stimulatory effect (about 12muunits of insulin/ml). The effects of insulin and glucagon appeared to be mediated completely independently, and were approximately quantitatively similar but opposite. These characteristics resulted in the mutual cancellation of the effects of the two hormones when they were both present at equally effective concentrations. 6. The implications of these findings with regard to current concepts about the mechanism of regulation of acetyl-CoA carboxylase and to the regulation of the enzyme in vivo are discussed.
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PMID:Inhibition of acetyl-CoA carboxylase activity in isolated rat adipocytes incubated with glucagon. Interactions with the effects of insulin, adrenaline and adenosine deaminase. 613 71

32P-labeled acetyl-CoA carboxylase was isolated from 32P-labeled rat epididymal fat pads by avidin-Sepharose affinity chromatography after exposure to epinephrine and insulin. Epinephrine led to an inactivation of the isolated enzyme by a reduction of Vmax, while the insulin stimulation observed in crude extracts did not survive enzyme purification. Both insulin and epinephrine caused only small increases in total 32P content of the enzyme. However, mapping of tryptic 32P-phosphopeptides by high performance liquid chromatography revealed that epinephrine and insulin stimulated the phosphorylation of 32P-peptides specific for each hormone. The major 32P-peptide phosphorylated by epinephrine co-migrated with the major 32P-peptide phosphorylated in vitro by the cAMP-dependent protein kinase, while the 32P-peptide phosphorylated in response to insulin co-migrated with that phosphorylated by casein kinase-I and casein kinase-II. The effects of epinephrine on carboxylase activity and phosphorylation can thus be accounted for by the expected epinephrine-induced activation of the cAMP-dependent protein kinase. While the increase in site-specific phosphorylation caused by insulin cannot be directly linked to insulin-induced activation in crude extracts, these data suggest that casein kinase-I and/or casein kinase-II may mediate the insulin-stimulated phosphorylation of acetyl-CoA carboxylase.
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PMID:Stimulation of site-specific phosphorylation of acetyl coenzyme A carboxylase by insulin and epinephrine. 613 73

Intravenous administration of methacholine (200 micrograms/kg) caused no changes in the seminiferous tubules of rats, but significantly increased intraluminal pressures and contractility of the caput, the corpus and the cauda epididymidis. The effect of methacholine was abolished by pretreatment with atropine (500 micrograms/kg), but not by phentolamine (400 micrograms/kg) or propranolol (400 micrograms/kg). Adrenaline (5-40 micrograms/kg), noradrenaline (5-40 micrograms/kg) and phenylephrine (100-400 micrograms/kg) had no effect on the seminiferous tubules, but dose-dependently elevated intraluminal pressures and enhanced the contractility of all regions of the epididymis. Isoproterenol (100-800 micrograms/kg) did not affect intraluminal pressures of the seminiferous tubules and the epididymal duct. The stimulatory effect of adrenergic agonists was specifically blocked by phentolamine, but not by propranolol or atropine. Cholinergic and adrenergic antagonists did not alter spontaneous contraction of the epididymis. The results suggest that the contractility of all segments of the rat epididymis, but not the seminiferous tubules, can be increased by autonomic drugs. The enhancing effect of adrenergic drugs is probably the result of activation through alpha-adrenergic receptors.
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PMID:Effects of cholinergic and adrenergic drugs on intraluminal pressures and contractility of the rat testis and epididymis in vivo. 614 94


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