Thymoquinone (TQ) is a bioactive component found in many medicinal herbs. In this study, we report the smooth and cardiac muscle relaxant activities of this compound. TQ concentration dependently suppressed spontaneously contracting rabbit jejunum while also relaxed high K(+)-(80 mM) induced contractions in jejunum and guinea-pig ileum, indicating activity at voltage-operated Ca(++) channels (V...

Radiofrequency catheter ablation has been used for treating cardiac arrhythmias, such as premature ventricular contractions and accessory pathway. We report two cases with successful ablation of left-sided accessory pathways and premature ventricular contractions from mitral annulus with one ablation. To our knowledge, no similar reports have been found so far.

Four of 220 patients without bifasicular block (complete right bundle branch block and left anterior hemiblock) or transient complete heart block immediately after surgery had an unexpected cardiac arrest one to 15 years after satisfactory surgical repair of tetralogy of Fallot. The postoperative electrocardiograms (ECG) revealed complete right bundle branch block in two patients and no intrave...

The effects of involuntary respiratory contractions on the cerebral blood flow response to maximal apnoea is presently unclear. We hypothesised that while respiratory contractions may augment left ventricular stroke volume, cardiac output and ultimately cerebral blood flow during the struggle phase, these contractions would simultaneously cause marked 'respiratory' variability in blood flow to ...

Tightly regulated Ca(2+) homeostasis is a prerequisite for proper cardiac function. To dissect the regulatory network of cardiac Ca(2+) handling, we performed a chemical suppressor screen on zebrafish tremblor embryos, which suffer from Ca(2+) extrusion defects. Efsevin was identified based on its potent activity to restore coordinated contractions in tremblor. We show that efsevin binds to VDA...

BACKGROUND Compared to eccentric contractions, concentric contractions result in higher cardiovascular stress. However, we do not know how these two types of contractions influence cardiac autonomic modulation during the post-exercise recovery period. OBJECTIVE to compare the effect of resistance training that is performed with concentric vs. eccentric emphasis on muscle strength and on post-...

The energy output of rabbit papillary muscle is examined and it is shown that there is more energy liberated in an afterloaded isotonic contraction than in an "equivalent" isometric contraction. This statement holds true regardless of whether equivalence is based on the proposition that tension or the time integral of tension is the best index of muscle energy expenditure. Besides the external ...

Turkmen horse is one of the oldest and purest breeds in the world, but there is no information on Doppler echocardiographic parameters in this horse. In the present study, pulsed-wave (PW) Doppler echocardiography was performed on 42 clinically normal 3- to 15-year-old racing Turkmen horses. No cardiac disease was detected with two-dimensional (2-D) real-time, M-mode, and colour flow mapping. D...