Monounsaturated fatty acids such as oleic acid are cardioprotective, modify the physicochemical properties of cardiomyocyte membranes, and affect the electrical stability of these cells by regulating the conductance of ion channels. We have designed a nonhydrolysable oleic acid derivative, 2-hydroxyoleic acid (2-OHOA), which regulates membrane lipid structure and cell signaling, resulting in be...

Myocardial regional function during acute coronary artery occlusion was studied using ultrasonic dimension gauges in open-chest dogs. Three pairs of 2mm ultrasonic crystals were implanted 1 cm apart near the endocardium in an ischemic segment, a control segment, and a segment at the margin of the ischemic zone. In the ischemic segment, coronary artery occlusion resulted in prompt dyskinesis whi...

Attached, spread, chick heart fibroblasts were induced to shorten by treatment with the ionophore, A23187. The shortening resulted from the retraction of the leading lamellae and other major cell processes. The response was dependent on external calcium with a threshold close to, and a maximal effect at, physiological concentrations. The shortening was also induced in Colcemid-treated cells and...

BACKGROUND Dyssynchrony of myocardial deformation is usually described in terms of variability only (e.g. standard deviations SD's). A description in terms of the spatio-temporal distribution pattern (vector-analysis) of dyssynchrony or by indices estimating its impact by expressing dyscoordination of shortening in relation to the global ventricular shortening may be preferential. Strain echoca...

We examined the effects of odorant inhalation on the sleep-wake states in rats. Odorants used in the experiment were clove, jasmine, lavender, lemon, peppermint, pine, rose, sandalwood, valerian, and ylang-ylang. Valerian and rose inhalation significantly prolonged the pentobarbital-induced sleeping time, whereas lemon inhalation significantly shortened it. The effect of valerian inhalation was...

the reproductive performance of a dairy herd has a significant effect on the profitability of that herd. common measures of reproductive performance are days to first service, days to conception, calving interval, services per conception, conception rate, estrus detection rate, and pregnancy rate. most cow operations would benefit economically by reducing the number of operational days, decreas...

Endothelin (ET)-1 is a potent positive inotropic agent, the effects of which are mediated by increases in cytosolic Ca(2+) in the myocardium. The object of this study was to examine 1) the influence of ET(A) and ET(B) receptor subtypes, and 2) the role of the phospholipase C (PLC) pathway in mediating ET-1-induced contraction. Left ventricular cardiomyocytes were isolated from the hearts of New...

Myocardial function is enhanced by endurance exercise training, but the cellular mechanisms underlying this improved function remain unclear. The ability of the myocardium to perform external work is a critical aspect of ventricular function, but previous studies of myocardial adaptation to exercise training have been limited to measurements of isometric tension or unloaded shortening velocity,...

Airway hyperresponsiveness (AHR) is a characteristic feature of asthma. It has been proposed that an increase in the shortening velocity of airway smooth muscle (ASM) could contribute to AHR. To address this possibility, we tested whether an increase in the isotonic shortening velocity of ASM is associated with an increase in the rate and total amount of shortening when ASM is subjected to an o...

A spontaneous contraction (SC) wave propagates among sarcomeres in heart muscle by the mechanism of Ca(++)-induced release of Ca++ from sarcoplasmic reticulum (SR). In the present study, some characteristics of unloaded shortening during the SC and its effect on a subsequent, electrically triggered twitch (Tsc) were examined at a sarcomere level in isolated rat myocytes. The results were compar...