Biology subjects

Ferner, K.

Publications and source records attributed to Ferner, K..

2 recordsLinked to original sources

bioRxiv2024

Development of the pulmonary vasculature in the gray short-tailed opossum (Monodelphis domestica) - 3D reconstruction by microcomputed tomography

The marsupial gray short-tailed opossum (Monodelphis domestica) is born at the late canalicular stage of lung development and the lungs are structurally immature compared to eutherians. The majority of lung development, including the maturation of pulmonary vasculature, takes place in ventilated functioning state during the postnatal period. The current study uses X-ray computed tomography ({micro}CT) to three-dimensionally reconstruct the vascular trees of the pulmonary artery and pulmonary vein in the marsupial gray short-tailed opossum to investigate the vascular genesis during the postnatal period. The development of the pulmonary vasculature was examined in 15 animals from neonate to postnatal day 57. The final 3-D reconstructions of the pulmonary artery and pulmonary vein in the neonate and at 21, 35 and 57 dpn were transformed into a centerline model of the vascular trees. Based on the reconstructions, the generation of end-branching vessels, the median and maximum generation and the number of vessels were calculated for the lungs. The pulmonary vasculature follows the lung anatomy with six pulmonary lobes indicated by the bronchial tree. The pulmonary arteries follow the bronchial tree closely, in contrast to the pulmonary veins, which run between the pulmonary segments. At birth the pulmonary vasculature has a simple branching pattern with a few vessel generations. Compared to the bronchial tree, the pulmonary vasculature appears to be more developed and extends to the large terminal air spaces. The pulmonary vasculature of the lungs from neonate to postnatal day 57 develops along the bronchial tree and shows a marked gain in volume and a progressive increase in vascular complexity and density. The gray short-tailed opossum resembles the assumed mammalian ancestor and is suitable to inform on the evolution of the mammalian lung. Vascular genesis in the marsupial bears resemblance to developmental patterns described in eutherians. Lung development in general seems to be highly conservative within mammalian evolution.

developmental biology↗

bioRxiv2023

Development of the terminal airspaces in the Gray short-tailed opossum ( ) - 3 D reconstruction by microcomputed tomography

Marsupials are born with structurally immature lungs when compared to eutherian mammals. The Gray short-tailed opossum (Monodelphis domestica) is born at the late canalicular stage of lung development. Despite the high degree of immaturity, the lung is functioning as respiratory organ, however supported by the skin for gas exchange during the first postnatal days. Consequently, the majority of lung development takes place in ventilated functioning state during the postnatal period. X-ray computed tomography ({micro}CT) was used to three-dimensionally reconstruct the terminal airspaces in order to reveal the timeline of lung morphogenesis. In addition, lung and air space volume as well as surface area were determined to assess the functional relevance of the structural changes in the developing lung. The development of the terminal air spaces was examined in 35 animals from embryonic day 13, during the postnatal period (neonate to 57 days) and in adults. At birth, the lung of M. domestica consists of few large terminal air spaces, which are poorly subdivided and open directly from short lobar bronchioles. During the first postnatal week the number of smaller terminal air spaces increases and numerous septal ridges indicate a process of subdivision, attaining the saccular stage by 7 days. The 3 D reconstructions of the terminal air spaces demonstrated massive increases in air sac number and architectural complexity during the postnatal period. Between 28 and 35 days alveolarization started. Respiratory bronchioles, alveolar ducts and a typical acinus developed. With alveolarization the volume of the air spaces and the surface area for gas exchange increased markedly. The structural transformation from large terminal sacs to the final alveolar lung in the Gray short-tailed opossum follows similar patterns as described in other marsupial and placental mammals. The processes involved in sacculation and alveolarization during lung development seem to be highly conservative within mammalian evolution.

developmental biology↗