What does PI stand for?

The apoptosis of HepG2 cells was determined by flow cytometry using propidium iodide fluorescence staining.

They cover neuronal death and neuroprotection, the use of propidium iodide to assess excitotoxic neuronal death in primary mixed cortical cultures, a modified silver technique for assessment of neuronal and axonal degeneration, a model of acute injury to study neuroprotection, a tool to study the molecular and cellular regulation of axonal regeneration and collateral sprouting in vitro, the role of Nrf2-dependent ARE-driven antioxident pathways in neuroprotection, biochemical methods to assess the coupling of brain energy metabolism in control and disease states, functioning cloning of genes regulating apoptosis in neuronal cells, intracerebral infusion, cell-penetrating peptides, and stem cells as a potential treatment.

Materials and methods Chemicals JC-1 and propidium iodide were from Molecular Probes (Eugene, OR, USA); Z-Val-Ala-Asp-fluoro-methylketone (zVAD-fmk) and Z-Phe-Ala-fluor-methylketone (zFA-fmk) were from Enzyme Systems Products (Livermore, CA, USA); Alexa Fluor 633 labelled annexin V was a kind gift of Dr.

Propidium iodide was included to measure alterations in DNA content including the induction of apoptosis.

Cells were stained with 1 [micro]g/mL propidium iodide (Wako) for 20 min on ice and analyzed under a fluorescence microscope (E400; Nikon, Tokyo, Japan) with-excitation at 535 nm, as described (23).

The Guava Cell Cycle assay uses the nuclear DNA stain propidium iodide (PI) to directly discriminate cells at different stages of the cell cycle.

Propidium iodide and digitonin were purchased from Aldrich-Chemie (Germany).

Cells were counterstained with either 4'-6-diamidino-2-phenylindole (DAPI) or propidium iodide and covered with a glass coverslip prior to microscopic analysis using a fluorescent microscope equipped with a triple band pass (Omega Optical Inc, Brattleboro, Vt).