Cerebral phosphoinositide, triacylglycerol and energy metabolism during sustained seizures induced by bicuculline

Shinichi Yoshida, Masuhiro Ikeda, Raul Busto, Mercedes Santiso, Elena Martinez, Myron D. Ginsberg

Research output: Contribution to journalArticlepeer-review

15 Scopus citations

Abstract

In ventilated rats, levels of phosphatidylinositol (PI), phosphatidylinositol 4-phosphate (PIP), phosphatidylinositol 4,5-biphosphate (PIP2), diacylglycerol (DAG), triacylglycerol (TAG), free fatty acids (FFA) and phosphatidic acid, as well as their fatty acid contents, were measured in forebrain tissue after 1, 20 and 60 min of seizures induced by bicuculline. Cerebral energy state was also measured. PI decreased progressively throughout 60 min of seizures, whereas the levels of PIP and PIP2 did not change. DAG increased modestly and persistently. FFA increased markedly during the early seizure period, but decreased later. Following an initial drop, TAG rose above control. Phosphatidic acid did not change. The levels of ATP and energy charge potential decreased slightly and lactate accumulated. Stearic acid (18:0) and arachidonic acid (20:4) primarily accounted for the changes in the levels of the lipids. At the onset of seizures, the decrease of 18:0 and 20:4 in PI occurred in parallel with an enrichment of these fatty acids in FFA and DAG. Despite the fact that the losses of 18:0 and 20:4 from PI were quantitatively similar to each other at all times examined, the increase in free 18:0 was much larger than the increase in free 20:4 at 20 min of seizures. Concurrently there was a rise of 20:4 in TAG. As the FFA levels declined thereater, 20:4 and docosahexaenoate (22:6) in TAG continued to increase. The results are consistent with the view that seizure activity stimulates the hydrolytic breakdown of brain phosphoinositides-the pathway catalyzed by phosphodiesterase of the phospholipase C type followed by lipases, and probably the pathway catabolized by phospholipases A as well. Preferential incorporation of polyunsaturated fatty acids into TAG-acyl residues may represent a mechanism to reduce the level of their free forms when the latter are produced in large amounts.

Original languageEnglish (US)
Pages (from-to)114-124
Number of pages11
JournalBrain Research
Volume412
Issue number1
DOIs
StatePublished - May 26 1987

Keywords

  • Diacylglycerol
  • Free fatty acid
  • Phosphatidylinositol
  • Rat
  • Seizure
  • Triacylglycerol

ASJC Scopus subject areas

  • Developmental Biology
  • Molecular Biology
  • Clinical Neurology
  • Neuroscience(all)

Fingerprint Dive into the research topics of 'Cerebral phosphoinositide, triacylglycerol and energy metabolism during sustained seizures induced by bicuculline'. Together they form a unique fingerprint.

Cite this