Early Acute Necrosis and Delayed Apoptosis Induced by Methyl Mercury in Murine Peritoneal Neutrophils

$48.00 plus tax (Refund Policy)

Download / Buy Article:

Abstract:

Abstract:

There is growing evidence that heavy metals in general, and mercurial compounds in particular, are immunotoxic. The purpose of this study was to explore the mechanism of MeHg in inducing cell death of mouse peritoneal neutrophils. In this paper we demonstrate that MeHg induces apoptosis and necrosis depending on MeHg concentration. In vitro exposure of mouse peritoneal neutrophils to MeHg resulted in a time- and concentration-dependent cell death. MeHg (15 μM) induced neutrophil necrosis in 13 min. The type of cell death was attributed to necrosis based on cells permeable to the fluorescent dye, propidium iodide and DNA appeared as a smear. With fura-2 microfluorimetric technique, we found that the entry of external Ca2+ into the cytosol played a crucial role in inducing cell necrosis by 15 μM MeHg. However, at lower concentrations, MeHg (10 μM)-induced apoptosis is confirmed by the observation of morphological features characterised by apoptotic bodies and fragmented DNA ladder. MeHg (10 μM) caused an immediate fall in pHi as revealed by the pH-sensitive fluorescent probe 2′7′-bis (carboxyethyl)-5(6)-carboxyfluorescein. We have found that MeHg induced cellular acidification prior to DNA fragmentation so as the other two apoptosis-inducing agents (ZnCl2 and EGTA). Furthermore, acid-activated endonuclease was increased by MeHg in neutrophils, which we considered to play a possible role in chromatin digestion leading to apoptosis. Taken together, these findings indicate that MeHg induces necrosis at higher concentrations by a rapid increase of [Ca2+]i and apoptosis at lower concentrations by acid activation of endonuclease.

Document Type: Research Article

DOI: http://dx.doi.org/10.1111/j.1742-7843.2004.pto940604.x

Affiliations: Institute of Pharmacology, College of Medicine, National Taiwan University, Taipei, and Department of Cosmetic Science, Chia-Nan University of Pharmacy and Science, Tainan, Taiwan

Publication date: June 1, 2004

More about this publication?
  • Formerly Pharmacology & Toxicology
Related content

Tools

Favourites

Share Content

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more