Premium
Inositol 1,4,5‐trisphosphate accumulation in brain of lithium‐treated rats
Author(s) -
Ishima Yoshio,
Fujimagari Michiyo,
Masuzawa Yasuo,
Waku Keizo
Publication year - 1993
Publication title -
lipids
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.601
H-Index - 120
eISSN - 1558-9307
pISSN - 0024-4201
DOI - 10.1007/bf02536049
Subject(s) - phosphatidylinositol , inositol , lithium (medication) , inositol phosphate , endocrinology , medicine , clinical chemistry , chemistry , pi , mechanism of action , inositol trisphosphate , lipidology , pharmacology , biochemistry , receptor , signal transduction , in vitro
The mechanism of action of lithium as a drug for patients with affective disorders was investigated. Three‐week‐old male rats were orally administered 2.7 mEq Li 2 CO 3 /kg/d for 1 or 3 wk, and phosphatidylinositol (PI), phosphatidylinositol 4‐phosphate (PIP), phosphatidylinositol 4,5‐bisphosphate (PIP 2 ), inositol phosphate (IP), inositol diphosphate (IP 2 ) and inositol triphosphate (IP 3 ) levels in brain were measured. The levels of IP were increased 1.7 and 2.4 times after 1 wk and 3 wk of lithium administration, respectively, while PI, PIP, PIP 2 , IP 2 and IP 3 levels were not altered. IP 3 was further fractionated by high‐performance liquid chromatography into I‐1,3,4‐P 3 and I‐1,4,5‐P 3 . In the control rat brain, the relative percentages of I‐1,3,4‐P 3 and I‐1,4,5‐P 3 were 95.8 and 4.2, respectively. However, after 3 wk of lithium administration, the values were changed to 69.6 and 30.3%, respectively. This increase in the neurotransducer I‐1,4,5‐P 3 in the brain may be relevant to the mechanism of action in the lithium treatment of patients with manic‐depressive disorders.