The role of skeletal blood flow in determining the uptake of99mTc-methylene diphosphonate

In this work we present a one-dimensional (1D) mathematical model of the coronary circulation and use it to study the effects of arrhythmias on coronary blood flow (CBF). Hydrodynamical models are rarely used to study arrhythmias’ effects on CBF. Our model accounts for action potential duration, which updates the length of systole depending on the heart rate. It also includes dependency of stroke volume on heart rate, which is based on clinical data. We apply the new methodology to the computational evaluation of CBF during interventricular asynchrony due to cardiac pacing and some types of arrhythmias including tachycardia, bradycardia, long QT syndrome and premature ventricular contraction (bigeminy, trigeminy, quadrigeminy). We find that CBF can be significantly affected by arrhythmias. CBF at rest (60 bpm) is 26% lower in LCA and 22% lower in RCA for long QT syndrome. During bigeminy, trigeminy and quadrigeminy, respectively, CBF decreases by 28%, 19% and 14% with respect to a healthy case.

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The role of adenosine in the regulation of cerebral blood flow: antagonistic effects of theophylline, an adenosine receptor blocker, on adenosine- and hypoxia-induced vasodilation of rat cerebral microvessels

The Japanese Journal of Pharmacology ◽

10.1016/s0021-5198(19)58912-0 ◽

1986 ◽

Vol 40 ◽

pp. 31

Author(s):

Seiji Morii ◽

Al C. Ngai ◽

H. Richard Winn

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Adenosine Receptor ◽

Receptor Blocker ◽

Cerebral Microvessels ◽

Antagonistic Effects

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Sound Richness of Music Might Be Mediated by Color Perception: A PET Study

Behavioural Neurology ◽

10.1155/2015/241804 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Masayuki Satoh ◽

Ken Nagata ◽

Hidekazu Tomimoto

Keyword(s):

Blood Flow ◽

Cerebral Blood Flow ◽

Multisensory Integration ◽

Regional Cerebral Blood Flow ◽

Traditional Music ◽

Simple Condition ◽

Regional Cerebral Blood ◽

Subtraction Technique ◽

Posterior Portion

Objects. We investigated the role of the fusiform cortex in music processing with the use of PET, focusing on the perception of sound richness.Method. Musically naïve subjects listened to familiar melodies with three kinds of accompaniments: (i) an accompaniment composed of only three basic chords (chord condition), (ii) a simple accompaniment typically used in traditional music text books in elementary school (simple condition), and (iii) an accompaniment with rich and flowery sounds composed by a professional composer (complex condition). Using a PET subtraction technique, we studied changes in regional cerebral blood flow (rCBF) in simple minus chord, complex minus simple, and complex minus chord conditions.Results. The simple minus chord, complex minus simple, and complex minus chord conditions regularly showed increases in rCBF at the posterior portion of the inferior temporal gyrus, including the LOC and fusiform gyrus.Conclusions. We may conclude that certain association cortices such as the LOC and the fusiform cortex may represent centers of multisensory integration, with foreground and background segregation occurring at the LOC level and the recognition of richness and floweriness of stimuli occurring in the fusiform cortex, both in terms of vision and audition.

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