Abstract |
To investigate microvascular hyperpermeability and thrombosis induced by photodynamic therapy or light/ dye treatment, we quantified the initiation time for thrombus formation, thrombus growth rate, and the time for the microvessel occlusion in post-capillary venules of rat mesenteries. Under similar light/ dye treatments, we also measured the microvessel hydraulic conductivity (Lp) and solute permeability (P) to TRITC-BSA ( bovine serum albumin), respectively, in the same type of microvessels as for thrombosis. Under an irradiation power of 0.37 mW/mm(2), thrombus was initiated in 3.8 ± 0.4 min, its growth rate was 3.9 ± 0.3% of the vessel mid-plane area/min, and the microvessels were completely occluded in 29.3 ± 2.2 min (SE, n = 8). Under the same irradiation power, Lp and P increased gradually, reaching a plateau in 3-5 min. At the plateau, Lp had increased to 2.2 ± 0.2 times (n = 11), while P had increased to 4.1 ± 0.7 (n = 7) times their baseline values, respectively. Neither Lp nor P increased further after longer time exposure (up to 30 min). Comparison of the measured Lp and P data with predictions from a mathematical model for the inter-endothelial cleft suggests that an almost complete depletion of the glycocalyx layer at the luminal surface of the endothelium might be one of the structural mechanisms by which the light/ dye increases microvascular permeability and induces thrombosis.
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Authors | Qin Liu, Min Zeng, Bingmei M Fu |
Journal | Biomechanics and modeling in mechanobiology
(Biomech Model Mechanobiol)
Vol. 10
Issue 2
Pg. 235-47
(Apr 2011)
ISSN: 1617-7940 [Electronic] Germany |
PMID | 20532586
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)
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Chemical References |
- Albumins
- Coloring Agents
- Rhodamines
- tetramethylrhodamine isothiocyanate
- Fluorescein
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Topics |
- Albumins
(metabolism)
- Animals
- Blood Cells
(drug effects, radiation effects)
- Capillary Permeability
(drug effects, radiation effects)
- Coloring Agents
(pharmacology)
- Female
- Fluorescein
(pharmacology)
- Light
- Models, Biological
- Rats
- Rats, Sprague-Dawley
- Rhodamines
(metabolism)
- Thrombosis
(physiopathology)
- Time Factors
- Venules
(drug effects, physiopathology)
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