Wyniki wyszukiwania - Biblioteka Nauki

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

Znaleziono wyników: 4

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: PHOSPHOLIPID

Sortuj według:

Ogranicz wyniki do:

Phospholipid content and lamellar structures in the epididymal epithelial cells of rats treated chronically with lead acetate [Pb(II)]

100%

Wiszniewska B. , Marchlewicz M. , Piasecka M. , Wenda-Rozewicka L. , Swider-Al-Amawi M.

Folia Biologica

1998

tom 46

215-224

The electron-microscopic observations accomplished covered epididymal epithelial cells of rats receiving lead acetate for five times longer than the duration of one spermatogenesis. These cells were found to possess a large number of vacuoles and conglomerates containing plicated membranes or tightly packed myelin-like lamellar formations. Further observations also revealed the formation of lamellar structures in mitochondria, dilatation of cisternae in the Golgi apparatus, and increased phagocytosis of spermatozoa by epithelial cells. The presence of a large amount of membranous material correlated with the increased content of phospholipids in epididymal epithelial cells. It may be suggested that the presence of such a great quantity of lamellar structures in epididymal epithelial cells of rats treated chronically with lead is the result of several processes, including the augmented synthesis of membranes associated with encircling the deposits of lead, autophagy in the cells, as well as intensified phagocytosis of spermatozoa.

Light activation of phospholipase A2 in the photoreceptor of the crayfish (Procambarus clarkii)

88%

Kashiwagi T. , Meyer-Rochow V. B. , Nishimura K. , Eguchi E.

Acta Neurobiologiae Experimentalis

2000

tom 60

nr 1

9-16

Retinal lipids of crayfish, kept at 4oC under continuous darkness for 3 weeks, consisted mainly of phosphatidylcholine (PC) and phosphatidylethanolamine (PE); sphingomyelin (SM), phosphatidylinositol (PI) and phosphatidylserine (PS) were minor contributors. PI, involved in the phototransduction cascade, never reached greater concentrations than 7% of the total. High concentrations of polyunsaturated fatty acids (PUFA) such as 20:4n-6, 20:5n-3 and 22:6n-3 (DHA, docosahexaenoic acid) were present in PC, PE and PS, but scarce in SM and PI. In retinae of crayfish kept at 4oC in darkness for 3 weeks and then exposed to white light (6 h; ca. 4,500 lx), SM and PS remained seemingly unaffected. PC, however, significantly decreased within 10 min to 65% of the initial value and 50% at 180 min. To study the reduction of PC, lipids of retinae suspended in physiological solution with/without phospholipase C (PLC) and phospholipase A2 (PLA2) inhibitors such as DMDA (=DEDA), manoalide, ET-18-OCH3, and U-73122 were measured. Only free fatty acids (FFA) of retinae with inhibitors of PLA2 like DMDA and manoalide decreased. Retinae irradiated by white light for 3 h displayed a significant reduction of PC, compared with those that had remained in continuous darkness. However, the PC of retinae with PLA2-inhibitors was not decreased by light. Our results provide evidence that not only photoreceptor cell PLC, but also PLA2 is activated by light.

Molecular mechanisms regulating transport of low molecular substances in hepatocyte

88%

Zwierz K. , Wielgat P. , Borzym-Kluczyk M.

Postępy Higieny i Medycyny Doświadczalnej

2003

tom 57

nr 1

91-116

Transporters of sinusoidal and lateral membranes mediate uptake of inorganic and organic substances to hepatocyte. In hepatocyte lipophilic compounds are biotransformed (hydroxylated and conjugated) and excreted into bile and urine. Vectorial movement of solutes and water from blood to bile is maintained by pumps of ABC superfamily secreting bile salts (bile acid dependent flow) and other solutes: bilirubin, phospholipids, glutathione and inorganic salts (bile acid independent flow).

Distribution of major lipids and fatty acids of the estuarine gastropod mollusc Telescopium telescopium

75%

Rakshit S. , Bhattacharyya D. K. , Misra K. K.

Folia Biologica

1997

tom 45

83-87

Lipid fractions and fatty acid composition of different organs, viz., digestive gland, mantle, and foot of the gastropod Telescopium telescopium inhabiting estuarine waters of West Bengal, India were studied. Thin layer chromatography and subsequent colorimetric analyses revealed the presence of phospholipid, cholesterol, and, to a lesser extent, triglycerides. Considerable variation in the three classes of lipids was observed in the organs studied so far. Gas liquid chromatography analyses showed the presence of saturated fatty acids (16: 0, 18: 0, 14:0), monoenoics (18:1, 16:1, 20:1), and polyenoic fatty acids (22:5 w6, 20:5 w3, 18:2) in varying amounts in the three organs. This may be related with a specific function of the organ. Polyunsaturated fatty acids are present in fair amounts in T. telescopium. The occurrence of arachidonic acid (20:4) in this gastropod may be related to salinity, as was pointed out by other workers.