scholarly journals Real‐time continuous monitoring of myocardial blood flow response to dynamic exercise with laser Doppler flowmetry in conscious rats and mice

2012 ◽  
Vol 26 (S1) ◽  
Author(s):  
Hirotsugu Tsuchimochi ◽  
Takashi Sonobe ◽  
Mikiyasu Shirai
Keyword(s):  
Blood Flow ◽  
Myocardial Blood Flow ◽  
Real Time ◽  
Laser Doppler Flowmetry ◽  
Continuous Monitoring ◽  
Dynamic Exercise ◽  
Doppler Flowmetry ◽  
Conscious Rats ◽  
Flow Response ◽  
Rats And Mice

scholarly journals Laminar Analysis of Cerebral Blood Flow in Cortex of Rats by Laser-Doppler Flowmetry: A Pilot Study

1997 ◽  
Vol 17 (12) ◽  
pp. 1326-1336 ◽  
Author(s):  
Martin Fabricius ◽  
Nuran Akgören ◽  
Ulrich Dirnagl ◽  
Martin Lauritzen
Keyword(s):  
Blood Flow ◽  
Cerebral Cortex ◽  
Real Time ◽  
Optical Fibers ◽  
Laser Doppler Flowmetry ◽  
Laser Light ◽  
Laser Doppler ◽  
Flow Measurements ◽  
Doppler Flowmetry ◽  
Artificial Brain

Laser-Doppler flowmetry (LDF) is a reliable method for estimation of relative changes of CBF. The measurement depth depends on wavelength of the laser light and the separation distance of transmitting and recording optical fibers. We designed an LDF probe using two wavelengths of laser light (543 nm and 780 nm), and three separation distances of optical fibers to measure CBF in four layers of the cerebral cortex at the same time. In vitro comparison with electromagnetic flow measurements showed linear relationship between LDF and blood flow velocity at four depths within the range relevant to physiologic measurements. Using artificial brain tissue slices we showed that the signal for each channel decreased in a theoretically predictable fashion as a function of slice thickness. Application of adenosine at various depths in neocortex of halothane-anesthetized rats showed a predominant CBF increase at the level of application. Electrical stimulation at the surface of the cerebellar cortex demonstrated superficial predominance of increased CBF as predicted from the distribution of neuronal activity. In the cerebellum, hypercapnia increased CBF in a heterogeneous fashion, the major increase being at apparent depths of approximately 300 and 600 μm, whereas in the cerebral cortex, hypercapnia induced a uniform increase. In contrast, the CBF response to cortical spreading depression in the cerebral cortex was markedly heterogeneous. Thus, real-time laminar analysis of CBF with spatial resolution of 200 to 300 μm may be achieved by LDF. The real-time in depth resolution may give insight into the functional organization of the cortical microcirculation and adaptive features of CBF regulation in response to physiologic and pathophysiologic stimuli.

scholarly journals Real-time measurement of subepi- and subendocardial blood flow by laser-Doppler flowmetry

1992 ◽  
Vol 58 ◽  
pp. 106
Author(s):  
Katsuhiko Noguchi ◽  
Yoshihiko Ojiri ◽  
Takao Chibana ◽  
Junko Nakasone ◽  
Hakie Higuchi ◽  
...  
Keyword(s):  
Blood Flow ◽  
Real Time ◽  
Laser Doppler Flowmetry ◽  
Time Measurement ◽  
Laser Doppler ◽  
Doppler Flowmetry ◽  
Real Time Measurement

Peculiarities of microcirculation in periodont tissues in children of key age groups sufficient type 1 diabetes. Part II

2019 ◽  
Vol 24 (2) ◽  
pp. 108-119 ◽  
Author(s):  
B. N. Davydov ◽  
D. A. Domenyuk ◽  
S. V. Dmitrienko
Keyword(s):  
Diabetes Mellitus ◽  
Blood Flow ◽  
Type 1 Diabetes ◽  
Type 1 Diabetes Mellitus ◽  
Laser Doppler Flowmetry ◽  
Laser Doppler ◽  
Diabetic Microangiopathy ◽  
Healthy Children ◽  
Doppler Flowmetry

Relevance. Morpho-functional changes in peripheral circulation established in type 1 diabetes mellitus correlate with changes in central hemodynamics, allowing the use of microcirculation indicators as diagnostic and prognostic criteria for assessing the degree of functional vascular disorders. Identifcation of microcirculation features of the blood by the method of laser Doppler flowmetry in children with different experience of type 1 diabetes in key age categories.Materials and methods. The study included 67 children with type 1 diabetes mellitus aged 12-15 years with an experience of the disease from six months to ten years. The comparison group consisted of 38 healthy children. The state of the microvasculature was assessed by laser Doppler flowmetry using a laser analyzer for capillary blood flow LAKK-OP.Results. In children with an experience of type 1 diabetes of less than two years, microcirculation disorders in periodontal tissues correspond to the hyperemic form, accompanied by increased perfusion, a decrease in the amplitude of low-frequency oscillations, increased heart rate, high blood flling, and blood flow bypass. For children with an endocrinopathy experience of more than three years, microcirculation disorders correspond to a stagnant form, combined with a decrease in perfusion due to stagnation of blood in the venular link, endothelial domination with suppression of neurogenic and cardiac fluctuations, low efciency and redistribution of blood flow in favor of the nutritive link.Conclusions. With the increase in experience, the degree of compensation of type 1 diabetes, the progression of diabetic microangiopathy, it is advisable to designate two stages of development of microcirculatory disorders. Early – compensatory with active adaptation, including neurogenic and endothelial regulation mechanisms. Late – decompensation with passive adaptation, supporting the effectiveness of microcirculation due to myogenic control of regulation, shunting and increasing the rate of blood outflow.

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