Pressure system minima in the pressure field. The minima are called low-pressure areas, and the maxima are called high-pressure areas. A "High" is often shown as H, and a "low" is shown as L. Elongated areas of low pressure, or troughs, are sometimes plotted as thick, brown dashed lines down the trough axis. Isobars are commonly used to place surface boundaries from the horse latitudes poleward, while streamline analyses are used in the tropics. A streamline analysis is a series of arrows oriented parallel to wind, showing wind motion within a certain geographic area. Cs depict cyclonic flow or likely areas of
Low pressure receptors both an increase in heart rate and a decrease in vasopressin (ADH) secretion from posterior pituitary, and renin and aldosterone. The decrease in vasopressin secretion results in an increase in the volume of urine excreted, serving to lower blood pressure. In addition, stretching of atrial receptors increases secretion of atrial natriuretic peptide (ANP), which promotes increased water and sodium excretion through the urine. In the right atrium, the stretch receptors occur at the junction of the venae cavae. In the left atrium, the junction is at the pulmonary veins. Low pressure receptors Low pressure receptors are baroreceptors located in large