Truncus

The pulmonary trunk and pulmonary arteries larger than 500 pm or 1 mm in diameter are designated elastic pulmonary arteries. Their tunica media consists of multiple concentric elastic laminae separated by smooth muscle, collagen and ground substance containing proteoglycan. 

In tissue sections of the porcine pulmonary trunk, endothelial cells were specifically immunola-belled with both the monoclonal and polyclonal antibodies raised against vimentin (Schnittler et al. 1998). A moderate degree of staining intensity was observed in all endothelial cells of the pulmonary trunk. The pulmonary trunk contained a 2- to 2.5-fold higher amount of vimentin than the endocardial endothelium of the right ventricle. Cultured endothelial cells of the porcine pulmonary trunk displayed considerably higher amounts of vimentin than did freshly isolated cells. 

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Expose the aortic arch and great vessels (truncus brachiocepha-licus, arteria carotis communis sinister, and arteria subclavia sinistra). 

Fig. 3. Variations of the great vessels branches from aortic arch (cynomolgus and marmoset monkey). 1=Arteria subclavia dextra, 2=Arteria carotis communis dextra, 5=Truncus brachiocephalicus, 4=Arteria carotis communis sinistra, 5=Arteria subclavia sinistra, =Arcus aortae.

Fig. 4. Preparation of the fixed heart for visceral examination. Cut 1 Ventral view Open the right ventricle along the septum in baso-apical direction going trough the aorta and the truncus pulmonalis (cross pulmonary valve) dorsal view open right ventricle near the septum from the heart apex towards the right atrium (through tricuspidal valve). Cut2 Ventral view Open the left ventricle along the septum from the heart apex into the left atrium (through bicuspidal valve) dorsal view cut the wall of left ventricle from the heart apex towards the left atrium.

Fig. 9. Fleart evaluation, (a) Normal heart viewed from the anatomical right side of the embryo. The outflow tract forms a C" or a U shape (dotted line). TA— truncus arteriosus CC—conus cordis BC—bulbus cordis, (b) Normal heart viewed from anatomical leftside of the embryo. V—ventricle A—atrium. The two chambers form a peanut shape (dotted line) with the ventricle appearing slightly larger than atrium.

The truncus brachiocephalicus and the left CCA show a combined origin from the aortic arch in approximately 25% of cases. The left vertebral artery rarely arises directly from the arch proximal to the subclavian artery. Infrequently an aberrant right subclavian artery leaves the aorta distal to the left subclavian artery and crosses the mediastinum dorsal to the esophagus and is then called the arte-ria lusoria (Fig. 5.10). Elongations and ectasias of the aortic arch and supraaortal vessels, which can impair the imaging quality of the vessels, are often seen in elderly patients. 

Tetralogy of fallot Transposition of the great vessels Tricuspid atresia Truncus arteriosis ventricular septal defect (VSD) atrial septal defect (ASD) PDA... 

Electrolyte balance Hyperkalemia (6.0 mmol/1) has been reported in an 18-month-old child who had received long-term captopril after an elective operation on a type 1 truncus arteriosus defect [44 ]. The child also had anemia, presumed to be due to erythroid hypoplasia. 

Ahnaraz L, Gonzalez C, Obeso A. Effects of high potassium on the release of [3H]dopamine from the cat carotid body in vitro. J Physiol 1986 379 293-307. Berger PJ, Gibbins IL, Hards DK, Crosby LJ. The distribution and ultrastructure of sensory elements in the baroreceptor region of the truncus arteriosus of the lizard Trachydosaurus rugosus. Cell Tissue Res 1982 226 389-406. 

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