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)

ESR spectra were recorded from rat epididymal adipocyte ghosts labeled with the 5-nitroxide stearic acid spin probe, I(12,3). Polarity-corrected and approximate order parameters, that are sensitive to the flexibility of the incorporated label, were used to evaluate the membrane lipid fluidity. Addition of CaCl2 a 37 degrees C decreased the fluidity, as indicated by positive increases in the order parameters. The ordering effect of Ca2+ was concentration-dependent, reached saturation at approx. 3--4 mM, and was completely reversed by excess EGTA. Previous studies indicated that low- and high-affinity sites on adipocyte plasma membranes are able to bind 45Ca2+, and our results suggest that Ca2+-induced alterations in the lipid fluidity involve cation binding to low-affinity sites. The cellular movements of Ca2+ and, in particular, the binding of Ca2+ to the plasma membrane may play important roles in insulin's action on fat cell function. The possibility that insulin directly alters the membrane fluidity was tested by adding hormone to freshly-prepared I(12,3)-labeled adipocyte ghosts. Insulin, at concentrations (10(-6) M) that enhance glucose uptake into intact adipocytes, did not affect the fluidity of ghosts suspended in buffers with or without Ca2+. The fluidities of I(12,3)-labeled rat adipocyte ghosts or human erythrocyte ghosts were also unaffected by various forms of human growth hormone.
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PMID:Effect of calcium, insulin and growth hormone on membrane fluidity. A spin label study of rat adipocyte and human erythrocyte ghosts. 624 91

The biochemical basis for the observed depletion of adipose tissue in C57BL mice bearing a transplantable nonmetastasizing preputial gland tumor, ESR-586, has been investigated. The results have shown that there are a number of significant changes in both deposition and mobilization of lipid as the tumor grows. The first change, before the tumor reached 2 g, was a decline in the activity of adipose tissue lipoprotein lipase to levels normally found in starved animals. This was accompanied by a slight increase in lipoprotein lipase activity in heart and appearance of substantial activity in large tumors. Together, these would result in impaired uptake of exogenous fatty acids by adipose tissue, and dietary lipid would be directed away from storage. This was followed by a marked decline in endogenous lipid synthesis in adipose tissue which commenced when the tumor weighed between 2 and 3 g, as measured in vivo by the incorporation of radioactivity into lipid from tritiated water. The basal rate of lipolysis was enhanced 2-fold in epididymal fat pads from mice bearing tumors that weighed between 2 and 4 g, although there was no difference in the epinephrine-stimulated activity.
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PMID:Modified lipoprotein lipase activities, rates of lipogenesis, and lipolysis as factors leading to lipid depletion in C57BL mice bearing the preputial gland tumor, ESR-586. 724 77

We have examined the epididymal (caput, corpus and cauda) and ejaculated spermatozoa of bufallo-bull (Bubalus bubalis) employing microscopic and spectroscopic techniques. Fluorescein isothiocyanate conjugated lectins namely concanavalin A (Con A), Dolichos biflorus (DBA), Maclura pomifera (MPA), peanut agglutinin (PNA), soybean agglutinin (SBA) and wheat germ agglutinin (WGA) were used to study the changes in the sperm surface carbohydrate make up as the spermatozoa mature. Quantitative analysis of the lectin binding was made flow cytometrically. 31P-NMR (nuclear magnetic resonance) spectra of the sperms obtained from different regions (head, body and tail) of the epididymis and of the ejaculate were analyzed to assess their metabolic activity. And the kinetics of spin label reduction of these samples was monitored with ESR (electron spin resonance) spectroscopy. These observations are supplemented with the electron microscopic (SEM and TEM) examination of the epididymal and ejaculated spermatozoa.
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PMID:Spectroscopic and microscopic studies of buffalo-bull (Bubalus bubalis) spermatozoa. 838 30

PDC-109 is the main component of bovine seminal plasma and has been suggested to play an important role in the genesis of bovine sperm cells. Here, the effect of binding of PDC-109 to membranes on the structure and physical properties of the lipid phase was investigated. For that, ESR measurements were undertaken on model membranes (lipid vesicles) and on biological membranes (epididymal spermatozoa) by employing various spin-labeled phospholipids. We found that PDC-109 alters the membrane structure of lipid vesicles as well as of bovine epididymal spermatozoa in that the mobility of spin-labeled phospholipids was reduced in the presence of the protein. This immobilizing effect of the protein was not restricted to analogues of phosphatidylcholine but was also detected with spin-labeled phosphatidylethanolamine. However, the extent of immobilization was lower for phosphatidylethanolamine compared with phosphatidylcholine, supporting the lipid headgroup specificity of the protein. Besides phospholipid headgroups, the physical state of membrane lipids is also important for the interaction of PDC-109 with membranes, in that, e.g., the immobilizing effect of the protein on labeled lipids was larger in membranes above the phase transition temperature compared with the effect below this temperature. The results are of relevance for understanding the physiological role of PDC-109 in the genesis of sperm cells.
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PMID:Influence of the bovine seminal plasma protein PDC-109 on the physical state of membranes. 1144 79