Tatsuhisa Takahashi

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Cardiovascular responses were examined in seven healthy male subjects during 10 min of recovery in the upright or supine position following 5 min of upright cycle exercise at 80% peak oxygen uptake. An initial rapid decrease in heart rate (f c) during the early phase of recovery followed by much slower decrease was observed for both the upright and supine(More)
To examine the influence of light exercise on cardiac responses during recovery from exercise, we measured heart rate (HR), stroke volume (SV), and cardiac output (Q˙ c) in five healthy untrained male subjects in an upright position before, during, and after 10-min steady-state cycle exercise at an exercise intensity of 170 W, corresponding to a mean of 68(More)
The branching systems in our body (vascular and bronchial trees) and those in the environment (plant trees and river systems) are characterized by a fractal nature: the self-similarity in the bifurcation pattern. They increase their branch density toward terminals according to a power function with the exponent called fractal dimension (D). From a(More)
The purpose of the study was to characterize the effects of muscular contractions (the muscle pump) and body posture on cardiovascular responses during recovery from moderate exercise in the upright-sitting or supine positions. Heart rate (HR), stroke volume (SV), and cardiac output (CO) were measured in seven young male subjects at rest and during 10-min(More)
To determine the effects of muscle pump function on cardiac autonomic activity in response to quiet standing, we simulated the muscle pump effect by rhythmic lower-leg cuff inflation (RCI) with four cuff pressures of 0 (sham), 40, 80, and 120 mmHg at 5 cycles/min. The R-R interval (RRI) and beat-to-beat blood pressure (BP) were acquired in healthy subjects(More)
INTRODUCTION It has been suggested that apoptosis in cardiac remodeling after myocardial infarction (MI) occurs in cardiomyocytes and is critically involved in the process of postinfarct cardiac remodeling. We investigated the pathophysiological link between myocardial apoptosis and cardiovascular function by modulating apoptotic signal transduction(More)
To characterize a compensatory function of the dopaminergic system of residual dopamine (DA) neurons in the mesolimbic pathway with DA-depleting lesions, we compared tissue and extracellular concentrations of DA and its metabolites in the nucleus accumbens (NACC) of adult rats with neonatal 6-hydroxydopamine (6-OHDA) treatment with those of control rats(More)
PURPOSE Physiological shear stress is higher in the retinal microcirculatory network than in other organs. The effects of laminar shear stress on gene expression in human retinal microvascular endothelial cells (HRMECs) was investigated. METHODS Cultured HRMECs on glass plates were exposed to a laminar shear stress of 0, 1.5, 6, 15, 30, 60, or 100(More)
The recovery of post-exercise heart rate (HR) is enhanced by a procedure of cooling down; however, the mechanism of this facilitated reduction is unknown. To determine whether more cardiac vagal reactivation is associated with a decrease in HR following cool-down exercise, we examined high-frequency R-R interval variability (HF, 0.15-0.40 Hz), an index of(More)
To investigate the effect of the neural components associated with leg movements on the control of ventilation during recovery from exercise, we recorded the minute ventilation (VE), oxygen uptake (VO2), and carbon dioxide output (VCO2) of eight normal volunteers during recovery from moderate, steady-state cycle exercise (170 W). The recovery phases were(More)