Stimulus-induced accumulation of inositol tetrakis-, pentakis-, and hexakisphosphates in N1E-115 neuroblastoma cells.
When [3H]inositol-prelabelled N1E-115 cells were stimulated with carbamylcholine (CCh) (100 microM), high K+ (60 mM), and prostaglandin E1 (PGE1) (10 microM), a transient increase in [3H]inositol pentakisphosphate (InsP5) accumulation was observed. The accumulation reached its maximum level at 15 s and had declined to the basal level at 2 min. CCh, high K+, and PGE1 also caused accumulations of [3H]inositol 1,4,5-trisphosphate [Ins(1,4,5)P3], [3H]inositol 1,3,4,6-tetrakisphosphate [Ins(1,3,4,6)P4], and [3H]inositol hexakisphosphate (InsP6). Muscarine and CCh induced accumulations of [3H]Ins(1,4,5)P3, [3H]-Ins(1,3,4,6)P4, [3H]InsP5, and [3H]InsP6 with a similar potency and exerted these maximal effects at 100 microM, whereas nicotine failed to do so at 1 mM. With a slower time course, CCh, high K+, and PGE1 caused accumulations of [3H]-inositol 1,3,4-trisphosphate [Ins(1,3,4)P3] and [3H]inositol 1,3,4,5-tetrakisphosphate [Ins(1,3,4,5)P4]. In an N1E-115 cell homogenate, [3H]Ins(1,4,5)P3, [3H]Ins(1,3,4,5)P4, and [3H]Ins(1,3,4)P3 were converted to [3H]InsP5 through [3H]-Ins(1,3,4,6)P4. The above results indicate that Ins(1,3,4,6)P4, InsP5, and InsP6 are rapidly formed by several kinds of stimulants in N1E-115 cells.
Sasakawa
N
N
Department of Pharmacology, Keio University School of Medicine, Tokyo, Japan.
Nakaki
T
T
Kashima
R
R
Kanba
S
S
Kato
R
R
D000527:Alprostadil / Q000494:pharmacology*; D000818:Animals; D002217:Carbachol / Q000494:pharmacology*; D007295:Inositol Phosphates / Q000032:analysis / Q000378:metabolism*; D051379:Mice; D009447:Neuroblastoma / Q000737:chemistry / Q000378:metabolism* / Q000473:pathology; D010833:Phytic Acid / Q000032:analysis / Q000378:metabolism*; D011188:Potassium / Q000494:pharmacology*; D013997:Time Factors; D014407:Tumor Cells, Cultured / Q000737:chemistry / Q000378:metabolism / Q000473:pathology
D007295:Inositol Phosphates; C081655:inositol-1,3,4,5-tetrakisphosphate; C081653:inositol-1,3,4,6-tetrakisphosphate; C013571:inositol pentaphosphate; D010833:Phytic Acid; D002217:Carbachol; D000527:Alprostadil; D011188:Potassium