Abstract
In this study, the subcellular targets and cellular mechanisms of the photodynamic action of δ-aminolevulinic acid (5ALA) were investigated in rat mammary carcinoma cells (MTF7) in vitro. A constant dose of 5ALA (200 μg/ml) was given and the light dose was varied (20-480 J/cm2) The effects of PDT were examined at 0 hr, 3 hr, and 24 hr after the treatment using the following assays: 1) Trypan BlueDye Exclusion Assay: Cell Membrane Damage 2) MTT Assay: Mitochondrial Damage 3) 3H-Thymidine Incorporation Assay: DNA Synthesis 4) Cell Colony Formation Assay: Cell survival. The MTT and colony formation assays are the best predictors of cell survival early and late after treatment. Cell membrane damage and almost complete disruption of mitochondrial function are early mechanisms of 5ALA PDT cytopathic effect. Reduction of DNA synthesis is a later, and possibly, a secondary effect of disruption of mitochondrial function although this conjecture has to be explored further. Reduction of DNA synthesis and cell membrane damage show complicated relationships with light dose while loss of mitochondrial function and long term survival are essentially complete with the lowest light dose used in this study.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 18-27 |
| Number of pages | 10 |
| Journal | Proceedings of SPIE - The International Society for Optical Engineering |
| Volume | 2133 |
| DOIs | |
| State | Published - Jul 19 1994 |
| Externally published | Yes |
| Event | Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy III 1994 - Los Angeles, United States Duration: Jan 23 1994 → Jan 29 1994 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Computer Science Applications
- Applied Mathematics
- Electrical and Electronic Engineering