Abstract:
:Monitoring the spatio-temporal characteristics of microcirculation is crucial for studying the functional activities of biotissue and the mechanism of disease. However, conventional methods used to measure blood flow suffer from limited spatial resolution or the injection of exogenous substances or the need of scanning to obtain the dynamic of regional blood flow. Laser speckle imaging (LSI) technique makes up these disadvantages by obtaining the regional blood flow distribution with high spatio-temporal resolution without the need to scan. In this paper, LSI was introduced to investigate the dynamic responses of the rat mesenteric microcirculation to an incremental dose of phentolamine. The results showed that when the dose of phentolamine was less than 4 microg ml(-1), local application of phentolamine on the mesentery would increase the blood perfusion as the concentration increased. When the dose increased further, the improvement decreased. At a dose of 200 microg ml(-1), a microcirculation impediment was caused. At the same time, different responses between veinules and arterioles were manifested. These suggested that LSI is promising to be a useful contribution to drug development and testing.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Cheng H,Luo Q,Liu Q,Lu Q,Gong H,Zeng Sdoi
10.1088/0031-9155/49/7/020subject
Has Abstractpub_date
2004-04-07 00:00:00pages
1347-57issue
7eissn
0031-9155issn
1361-6560journal_volume
49pub_type
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