Evidence that free fatty acids in trophocytes of Periplaneta americana fat body may be regulated by the activity of phospholipase A2 and cyclooxygenase

1997 ◽  
Vol 27 (7) ◽  
pp. 681-692 ◽  
Author(s):  
Irshad Ali ◽  
John E Steele
Keyword(s):  
Fatty Acids ◽  
Phospholipase A2 ◽  
Free Fatty Acids ◽  
Periplaneta Americana ◽  
Fat Body

Histochemical and Morphological Studies of the Lipids in Oogenesis. I. Periplaneta americana

1958 ◽  
Vol s3-99 (47) ◽  
pp. 315-332
Author(s):  
VISHWA NATH ◽  
BRIJ L. GUPTA ◽  
BACHAN LAL
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Periplaneta Americana ◽  
Lipid Synthesis ◽  
Active Role ◽  
Lipid Bodies ◽  
Acetone Extraction ◽  
Morphological Studies ◽  
Carbohydrate Complex

1. Three kinds of lipid bodies have been described in the oogenesis of the cockroach, Periplaneta americana (i) L1 bodies, present in the earliest oocyte, which persist till the oocyte measures approximately mm and contain phoapholipids only, possibly having more lecithint than cephalins; (ii) L2bodies, which first arise in the oocyte measuring 0.4 mm and have a complete or incomplete sheath of phoapholipida surrounding a medulla of triglycerides (rather highly saturated); (iii) L3 bodies, which are the only type of lipids present in the oocytea measuring more than 0.65 mm and consist of triglycerides only (rather highly saturated). 2. Some of the larger L3 bodies give a ‘ringed’ or ‘crescentic’ appearance in Sudan black when used at room temperatures (12° C to 40° C) but appear mostly solid when this colouring agent is used at 6o° C. 3. Mitochondria, which remain as fine granules throughout the course of oogenesis, contain proteins and phospholipids. They seem to have some lipids which are masked normally but are unmasked after acetone extraction, with a resulting increase in sudanophilia. 4. Yolk globules appear in the oocytes meaauring approximately 0.5 mm. They contain a protein-carbohydrate complex. 5.The bacterioid objects described by earlier workers have been shown to contain phospholipids and free fatty acids. They possibly play an active role in the lipid synthesis of the cell.

Modulation of plasma membrane H+-ATPase from oat roots by lysophosphatidylcholine, free fatty acids and phospholipase A2

1988 ◽  
Vol 74 (1) ◽  
pp. 11-19 ◽  
Author(s):  
Michael Gjedde Palmgren ◽  
Marianne Sommarin ◽  
Peter Ulvlskov ◽  
Peter Leth Jorgensen
Keyword(s):  
Fatty Acids ◽  
Plasma Membrane ◽  
Phospholipase A2 ◽  
Free Fatty Acids

Hexachlorocyclohexanes affect the arachidonic acid release from phosphatidylinositol but not from other phospholipid classes in tubular cell cultures

1995 ◽  
Vol 15 (4) ◽  
pp. 191-199 ◽  
Author(s):  
J. C. Puente-Fraga ◽  
P. López-Aparicio ◽  
S. Senar ◽  
M. N. Recio ◽  
M. A. Pérez-Albarsanz
Keyword(s):  
Fatty Acids ◽  
Phospholipase A2 ◽  
Free Fatty Acids ◽  
Arachidonic Acid Release ◽  
Phospholipase Activity ◽  
Tubular Cells ◽  
Renal Tubular Cells ◽  
Phospholipid Classes ◽  
Acid Release ◽  
Renal Tubular

Gamma- and delta-isomers of hexachlorocyclohexane caused marked decreases in the levels of radioactive phospholipids, and increases in the levels of [3H]arachidonate incorporated into free fatty acids in rat renal tubular cells. The increased radioactivity of free fatty acids arises from the decrease of [3H]arachidonate incorporated into phosphatidylinositol, but not into phosphatidylcholine, phosphatidylserine or phosphatidylethanolamine. This fact suggests that phosphatidylinositol can be broken down to the fatty acid from the sn-2 position and lysophospholipid by a phospholipase activity increased by hexachlorocyclohexanes. The observed specific toxicant action could be achieved in two ways: (a) operating upon a specific phospholipase A2 that acts on phosphatidylinositol, but not on other phospholipids as substrates and/or (b) involving substrate-phospholipase A2 interactions. Interestingly, the observed effect of the γ-isomer was more pronounced than that of the γ-one.

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