ABSTRACT
Objective: Quantitative comparison between different layers of aorta in three age groups: neonate, young adult and old age of female guinea pig
Design:Histomorphometric study of 7 segments of the aorta by light microscope
Animals: A total of 15 female guinea pig [5 neonate, 5 young adult and 5 old age]
Procedure: Immediately following euthinization of animal, the whole aorta was collected and separated into the ascending aortae, aortic arch, cranial and caudal thoracic aortae, cranial, middle and caudal abdominal aortae segments. After fixation in 10% buffered formalin solution, the aortic segments were embedded in paraffin, and histological sections were made from each segment. The sections were stained with H andE and masson trichrome
Statistical analysis: One way analysis and Duncan tests by using of SPSS program
Results: It was observed that the greatest external and internal diameters and the thickest wall of the aorta occur in the ascending aorta. The percentage of the tunica interna and externa, as compared with the total wall thickness was increased gradually from the ascending aorta to the caudal abdominal aorta, whereas the tunica media was decreased
Clinical implication: External and internal diameters, wall thickness and the thickness of tunica interna and media were decreased from the ascending aorta to the caudal abdominal aorta, on the other hand the thickness of the tunica externa was increased