| 1. |
- Simonsson, Per, et al.
(author)
-
Bradykinin effects on phospholipid metabolism and its relation to arachidonic acid turnover in neuroblastoma x glioma hybrid cells (NG 108-15)
- 1989
-
In: Cellular Signalling. - : Elsevier BV. - 1873-3913 .- 0898-6568. ; 1:6, s. 587-598
-
Journal article (peer-reviewed)abstract
- In neuroblastoma x glioma hybrid cells (NG 108-15) labelled with [32P]-trisodium phosphate, [3H]-inositol and [14C]-arachidonic acid, bradykinin stimulated the hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP2) while it had no effect on the release of [14C]-arachidonic acid (AA). The effect on PIP2 was time- and dose-dependent with a maximal effect on [3H]-inositol- and [32P]-labelled cells after 10-30 s of stimulation with 10(-6) M bradykinin. However, the hydrolysis of [14C]-AA labelled PIP2 was delayed compared to the effect on [3H]- and [14C]-PIP2 and was not detectable until after 60 s of stimulation. Bradykinin stimulation resulted in an increased formation of [3H]-inositol phosphates (IP) and [32P]- and [14C]-phosphatidic acid (PA) but the time course for PA formation did not follow the time-course for PIP2 hydrolysis. A reduced labelling of [32P]- and [14C]-phosphatidylcholine was also found in stimulated cells suggesting that PA may derive from other sources than PIP2. In conclusion, our results indicate that bradykinin activates phospholipase C, but not phospholipase A2, in NG 108-15 cells.
|
|
| 2. |
- Simonsson, Per, et al.
(author)
-
Ethanol effects on bradykinin-stimulated phosphoinositide hydrolysis in NG 108-15 neuroblastoma-glioma cells
- 1989
-
In: Alcohol. - : Elsevier BV. - 0741-8329. ; 6:6, s. 475-479
-
Journal article (peer-reviewed)abstract
- The effect of short-and long-term ethanol exposure on bradykinin-stimulated hydrolysis of phosphatidylinositol 4.5-bisphosphate (PIP2) was investigated in neuroblastoma X glioma hybrid cells (NG 108-15). Acute exposure of 50-150 mM ethanol neither influenced the bradykinin-stimulated accumulation of [3H]-inositol phosphates (IP1, IP2, IP3) nor the hydrolysis of PIP2 in cells labelled with [3H]-inositol. Furthermore, ethanol (100 mM) added in the absence of agonist did not influence these parameters. However, in cells cultivated for 4 days in 100 mM ethanol, PIP2 hydrolysis and IP1, IP2 and IP3 formation after stimulation by 10(-6)-10(-5) M bradykinin was markedly inhibited while there was no effect on the basal levels or on the levels found after stimulation with low concentrations of bradykinin. The inhibitory effect of ethanol on IP accumulation became significant after 2-3 days of ethanol.
|
|
