The drop, introduced into the ventricle via a glass micropipette filled with the oil, remained in place and underwent deformation according to the cardiac cycle (Figure 1a) The introduction of this deformable drop, equivalent to the stroke volume of the heart, allowed the ventricle to work under nearly loaded conditions. Then the hearts were carefully transferred to an airtight stainless steel chamber (Figure 1b) following a slightly modified procedure previously described .Briefly, the spontaneously beating hearts were placed in the culture compartment (300 |J.L), which was separated from the gas compartment (300 |J.L) by a transparent, gas permeable (eg, oxygen, carbon dioxide) thin (15 |j.m) silicone membrane (RTV 141, Rhone Poulenc). You are always offered finest quality Generic Allegra at the pharmacy you can fully trust and enjoy being its customer. Why wouldn’t you, if it offers lowest prices in the industry and fast delivery that can be free for some orders?
Figure 1 a Spontaneously beating heart excised from three-day-old chick embryo. The ventricle was loaded with a drop (star) ofnon-toxic viscous silicone oil (Silbione V1000) which was deformed according to the cardiac cycle. The photographs represent the minimal (left) and maximal (right) deformations observed during diastole and systole, respectively. The circles approximately correspond to the microscope field used for photometric measurements along the heart tube. Atrioventricular and ventriculoconal junctions are indicated by filled and open arrowheads, respectively. A Atrium; C Conotruncus; V Ventricle. The bar represents 1 mm. b Schematic cross-section of the airtight chamber containing an embryonic heart. The chamber was separated into two compartments (V1 and V2, 300 цL each) by a transparent and thin silicone membrane facilitating gas exchange. Two glass windows (w) allowed observation and photometric measurements. Gas of selected composition flowed through compartment V1. Compartment V2 contained the culture medium and could be perfused by using remote controlled push-pull syringes allowing renewal of medium and application of substrates or drugs. The chamber was mounted onto the stage ofan inverted microscope equipped with a photometric device and a thermostabilized incubator (37°C). The edge of the image of the investigated region covered about half of the photometric detector (grey arrow). The star indicates the flattened drop of silicone oil introduced into the ventricle