Functional-morphology of the Coronary Supply of the Systemic Heart of Octopus-vulgaris

The ventricular wall of the systemic heart of Octopus vulgaris consists of longitudinal and circular layers of myocardial cells arranged in an alternate pattern. The use of the corrosion-cast method and scanning electron microscopy has shown that the ventricular wall is supplied through a very rich capillary network, from which a classic venular and venous system originates to ensure drainage. Evidence exists of direct communications between the capillary network and the ventricular lumen. The flow through the coronary system is driven by the ventricularpressure generated during systole. The oxygen extracted from the coronary output accounts for 80%-100% of the total consumption of the heart. In vitro, the coronary output is functionally related to the cardiac output and is highly dependent on the oxygen content of theperfusate, being lower at the highest oxygen levels. The in vitro coronary flow is affected by many humoral factors