Microvascular anatomy of the non‐lobulated liver of adult Xenopus laevis : A scanning electron microscopic study of vascular casts
| Autor: | Bernd Minnich, Alois Lametschwandtner, Udo M. Spornitz |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
0301 basic medicine
Histology Stromal cell Electrons Anastomosis Xenopus laevis 03 medical and health sciences Hepatic Artery 0302 clinical medicine Parenchyma medicine Animals Vein Ecology Evolution Behavior and Systematics Sprouting angiogenesis Plexus business.industry Blood flow Anatomy 030104 developmental biology medicine.anatomical_structure Lymphatic system Liver Microscopy Electron Scanning cardiovascular system business 030217 neurology & neurosurgery Biotechnology |
| Zdroj: | The Anatomical Record. 305:243-253 |
| ISSN: | 1932-8494 1932-8486 |
| Popis: | The microvascular anatomy of the non-lobulated liver of adult Xenopus laevis was studied by scanning electron microscopy of vascular corrosion casts. Hepatic portal veins and hepatic arteries entered hepatic lobes at the hiluses, hepatic veins left at these sites. Intraparenchymal, hepatic portal veins branched up to 10 times before terminal portal venules supplied liver sinusoids. Hepatic arteries closely followed portal vessels. Arteriolar side branches formed anastomoses with close by portal venules (arteriolar-portal anastomoses; APAs), liver sinusoids (arteriolar-sinusoidal anastomoses; ASAs), and peribiliary plexus vessels. Distally, hepatic arteries anastomosed with terminal portal venules having >100 μm in diameter. Liver sinusoids formed a dense three-dimensional network displaying signs of non-sprouting and sprouting angiogenesis evidenced by "holes" and blind ending tapering cast vascular structures (sprouts), respectively. Sinusoids drained via efferent hepatic veins. Right and left hepatic veins drained into the posterior caval vein. Locally, a dense honeycomb-like 3D-meshwork of resin structures was found around terminal portal venules and hepatic arteries. These networks were fed by hepatic arterioles and drained into adjacent terminal portal venules. As their morphologies differed significantly from sinusoids and they were found at sites where diffuse lymphoid tissue is described, we are convinced that they represent the vasculature of diffuse lymphoid tissue areas. Frequencies and diameter ratios of hepatic portal venules versus hepatic arterioles anastomosing with the former (APAs) implicate that the arterial supply contributes to the oxygenation of parenchymal and stromal cells rather than to a significant increase in blood flow towards hepatic sinusoids. |
| Databáze: | OpenAIRE |
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