NDLI: Age at time of infarction differentially affects the remodeling responses in viable cardiac tissue in young versus old rats

Content Provider	IEEE Xplore Digital Library
Author	Handley, S.M. Ngo, F. Hall, C. Allen, J. McLean, M. Lanza, G. Miller, J.G. Wickline, S.
Copyright Year	2001
Abstract	Ventricular remodeling after myocardial infarction elicits structural and functional changes that can compromise global cardiac function. To determine whether age influences this process, we characterized remodeling after myocardial infarction in Fischer 344 rats that undergo natural age-related changes in heart structure and function that parallel those observed in human hearts. Young (3 month, n=7) and old (18 month, n=7) rats underwent myocardial infarction by coronary occlusion. Sham-infarct procedures were performed in both groups as controls. Twelve weeks after infarction, hearts were excised, fixed, and sliced into 2 mm thick cross-sections. Ultrasonic RF signals were acquired with a 50 MHz transducer and integrated backscatter was calculated from 30 to 50 MHz. Heart slices were then stained and their images digitized to permit histology with computer assisted planimetry. Infarct sizes were similar in young and old rats (12.1/spl plusmn/2.4% and 11.6/spl plusmn/5.4%; p=NS). Integrated backscatter from the infarct scar tissue in both the young and old rats were similar, (-41.4/spl plusmn/1.2 dB vs. -42.7/spl plusmn/1.1 dB, p=NS). Integrated backscatter from the remodeled but non-infarcted viable tissue was -48.4/spl plusmn/0.8 dB and -45.4/spl plusmn/1.0 dB in young and old rats, respectively, both statistically different from integrated backscatter from scar tissue (p<0.05). Significantly, the integrated backscatter from the remodeled but viable non-infarcted regions of the old infarct rats was increased by 100% over that from the young rats (p<0.05). These data suggest that alterations in microscopic structure and material properties associated with remodeling of viable myocardial tissue differ depending on age, as delineated by quantitative acoustic microscopy.
Sponsorship	Ultrasonics, Ferroelectr., & Frequency Control Soc
Starting Page	1181
Ending Page	1184
File Size	170051
Page Count	4
File Format	PDF
ISBN	0780371771
DOI	10.1109/ULTSYM.2001.991929
Language	English
Publisher	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Publisher Date	2001-10-07
Publisher Place	USA
Access Restriction	Subscribed
Rights Holder	Institute of Electrical and Electronics Engineers, Inc. (IEEE)
Subject Keyword	Cardiac tissue Rats Heart Myocardium Backscatter Aging Senior citizens Humans Microscopy Material properties
Content Type	Text
Resource Type	Article

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in