Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2000 Aug 18;87(4):309-15.
doi: 10.1161/01.res.87.4.309.

Ischemic preconditioning activates phosphatidylinositol-3-kinase upstream of protein kinase C

Affiliations

Ischemic preconditioning activates phosphatidylinositol-3-kinase upstream of protein kinase C

H Tong et al. Circ Res. .

Abstract

The present study is designed to test whether phosphatidylinositol 3-kinase (PI3-kinase) has a role in the signaling pathway in ischemic preconditioning (PC) and whether it is proximal or distal to protein kinase C (PKC). Before 20 minutes of global ischemia, Langendorff-perfused rat hearts were perfused for 20 minutes (control); preconditioned with 4 cycles of 5-minute ischemia and 5-minute reflow (PC); treated with either wortmannin (WM) or LY 294002 (LY), each of which is a PI3-kinase inhibitor, for 5 minutes before and throughout PC; treated with 1,2-dioctanoyl-sn-glycerol (DOG), an activator of PKC for 10 minutes (DOG); treated identically to the DOG group except with WM added 10 minutes before and during perfusion with DOG; or treated with either WM or LY for 25 minutes. Recovery of left ventricular developed pressure (LVDP; percentage of initial preischemic LVDP), measured after 30 minutes of reflow, was improved by PC (72+/-2% versus 36+/-4% in control; P<0.001), and this was blocked by WM and LY (41+/-4% and 43+/-5%, respectively; P<0.05 compared with PC). DOG addition improved postischemic LVDP (67+/-6%; P<0.001 compared with control), but in contrast to its effect on PC, WM did not completely eliminate the protective effect of DOG (52+/-4%; P>0.05 compared with DOG; P<0.05 compared with control). PC induced phosphorylation of protein kinase B and translocation of PKC epsilon, and it increased NO production, and these effects were blocked by WM, which suggests a role for PI3-kinase in PC upstream of PKC and NO.

PubMed Disclaimer

Similar articles

Cited by

Publication types

MeSH terms

LinkOut - more resources