title: Caspase-3 Activity in the Rat Amygdala Measured by Spectrofluorometry After Myocardial Infarction.
abstract: Myocardial infarction (MI) has dramatic mid- and long-term consequences at the physiological and behavioral levels, but the mechanisms involved are still unclear. Our laboratory has developed a rat model of post-MI syndrome that displays impaired cardiac functions, neuronal loss in the limbic system, cognitive deficits and behavioral signs of depression. At the neuronal level, caspase-3 activation mediates post-MI apoptosis in different limbic regions, such as the amygdala - peaking at 3 days post-MI. Cognitive and behavioral impairments appear 2-3 weeks post-MI and these correlate statistically with measures of caspase-3 activity. The protocol described here is used to induce MI, collect amygdala tissue and measure caspase-3 activity using spectrofluorometry. To induce MI, the descending coronary artery is occluded for 40 min. The protocol for evaluation of caspase-3 activation starts 3 days after MI: the rats are sacrificed and the amygdala isolated rapidly from the brain. Samples are quickly frozen in liquid nitrogen and kept at -80 °C until actual analysis. The technique performed to assess caspase-3 activation is based on cleavage of a substrate (DEVD-AMC) by caspase-3, which releases a fluorogenic compound that can be measured by spectrofluorometry. The methodology is quantitative and reproducible but the equipment required is expensive and the procedure for quantifying the samples is time-consuming. This technique can be applied to other tissues, such as the heart and kidneys. DEVD-AMC can be replaced by other substrates to measure the activity of other caspases.
authors: Centre de Recherche, Hospital du Sacre-Coeur de Montreal.
authors: Kim
authors: K
authors: Gilbert
authors: Centre de Recherche, Hospital du Sacre-Coeur de Montreal.
authors: Roger
authors: R
authors: Godbout
authors: Centre de Recherche, Hospital du Sacre-Coeur de Montreal; Guy.Rousseau@umontreal.ca.
authors: Guy
authors: G
authors: Rousseau
mesh_terms: D000679:Amygdala / Q000201:enzymology*; D000818:Animals; D017209:Apoptosis / Q000502:physiology; D053148:Caspase 3 / Q000378:metabolism*; D008032:Limbic System / Q000201:enzymology / Q000473:pathology; D008297:Male; D009203:Myocardial Infarction / Q000201:enzymology* / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: C505410:Casp3 protein, rat; D053148:Caspase 3