Phosphatidylinositol turnover (PI) during synaptic activation results from the release of a stimulatory and in inhibitory agonist
PI has been implicated in the process of synaptic transmission and is increased by agonists. It has been suggested that PI is involved in cellular Ca/sup + +/ mobilization and the process represents a series of hydrolytic reactions with inositol as the final product. Hence, the rate of release of /sup 3/H-inositol (/sup 3/H-Ins) from prelabelled inositol phospholipids can be used as an index of PI. In the /sup 3/H-inositol prelabelled frog sympathetic ganglia, they studied the effect of synaptic activity on PI. PI did not change during orthodromic stimulation (20 Hz, 5 min). However, upon cessation of the stimulation, PI increased rapidly and remained elevated for at least 30 min. This increase in PI was reduced by suffusing the ganglia with either acetylcholine or adenosine. In the presence of atropine (5 ..mu..M), orthodromic stimulation increased PI. They hypothesized that synaptic activation releases a long-lasting stimulatory agonist and a short-lived inhibitory (Ach/adenosine) agonist(s) affecting PI. To test this idea, 2 sympathetic ganglia were used. One was prelabelled with /sup 3/H-inositol and the other was not. The two ganglia were placed together in a 5 ..mu..l drop of Ringers solution containing atropine. Orthodromic stimuli were applied to the non-labelled ganglion and elicited release of /sup 3/H-Ins from the non-stimulated ganglion.
- Research Organization:
- Univ. of Virginia, Charlottesville
- OSTI ID:
- 6802311
- Report Number(s):
- CONF-8604222-; TRN: 87-008609
- Journal Information:
- Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 45:4; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ADENOSINE
SECRETION
NERVES
BIOCHEMISTRY
PHOSPHOLIPIDS
METABOLISM
FROGS
INHIBITION
INOSITOL
TRACER TECHNIQUES
TRITIUM COMPOUNDS
AMPHIBIANS
ANIMALS
AQUATIC ORGANISMS
CARBOHYDRATES
CHEMISTRY
ESTERS
INOSITOLS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LIPIDS
MONOSACCHARIDES
NERVOUS SYSTEM
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
RIBOSIDES
SACCHARIDES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques