Hypoxia-Induced Endothelial Damage and Microthrombosis in Myocardial Vessels of Newborn Landrace/Large White Piglets

Abstract

Objective. Evaluating the presence of endothelial changes in myocardial vessels in an experimental model of hypoxia and resuscitation in newborn piglets. Methods. Fifty male Landrace/Large White neonatal piglets were studied: ten of them were allocated in group A (control group, SHAM-operated). In group B (forty animals, experimental group) normocapnic hypoxia was induced by decreasing inspired concentration of O2 to 6%–8%. When the animals developed bradycardia or severe hypotension, reoxygenation was initiated. The animals of group B were allocated in 4 subgroups of 10, according to the concentration of O2 they were resuscitated with (groups 1, 2, 3, and 4 received 18%, 21%, 40%, and 100% O2, resp.). Results. Control group animals did not show any significant endothelial lesions. Contrarily, endothelial lesions were detected in all experimental group cases. When these lesions were analyzed in the different heart zones, no significant difference in their incidence was observed; analyzing the frequency in the animals of the 4 subgroups, only microthrombosis showed a higher frequency in animals in groups 4 and 3. Conclusions. Endothelial damage represents a diffuse pathological feature in the myocardial vessels of piglets subjected to normocapnic hypoxia and resuscitation suggesting a possible role of hyperoxygenation in aggravating endothelial damage.

Hypobaric hypoxia affects the reproductive physiology of dairy cattle

“…Hypoxia is a primary reason for snoring, ischemic stroke, and heart disease; it can damage endothelial cells, hippocampal neurons, and myocardial cells, among many other cell types. These cell types play a critical role in the development and progression of these disorders (Wang et al, 1993;Feng et al, 2012;Faa et al, 2014). Studies have demonstrated that hypoxia damages and even kills cells primarily by oxidative stress, inflammation, acidosis (Distler et al, 2005;Guo et al, 2019), and apoptosis (Saraste and Pulkki, 2000).…”

“…A reduction in the diameter of foetal capillaries at high altitudes also characterises the vascular compartment of the placenta. This reduction in diameter may increase the surface area to volume ratio of the surface over which gas and nutrient exchange occur (Espinoza et al, 2001;Parraguez et al, 2010;Khalid et al, 2016). Similar reductions in foetal capillary width have been observed in humans that have adapted to live at high altitudes, which suggests that the rise in surface area to volume ratio is an adaptive response (Jackson et al, 1987).…”

Effects of Microvesicles on Cell Apoptosis under Hypoxia

“…Hypoxia, as the main pathological mechanism of sleep apnea hypopnea syndrome, ischemic stroke, ischemic heart disease, and many other diseases, can cause endothelial cells, hippocampus neurons, and myocardial cells, as well as many other cells, injury and plays an important role in development and progression of disease [1–3]. Many studies have found that hypoxia mediates cell injury and even cell death mainly through oxidative stress, inflammation, acidosis, and apoptosis.…”

Μελέτη Της Μεθόδου "Των Συνεχών Θωρακικών Συμπιέσεων" Σε Σύγκριση Με Την "Αναλογία 3:1" Στη Νεογνική Ασφυξία (Πειραματική Μελέτη)

“…Μεταγενέστερη αναδρομική μελέτη από τη Βορειοδυτική Ελλάδα έδειξε ότι το ποσοστό περιγεννητικής θνησιμότητας ελαττώθηκε σημαντικά από την περίοδο 1996-1999 μέχρι την περίοδο 2000-2004, καθώς και ότι η περιγεννητική ασφυξία δεν είναι πλέον η πρώτη αιτία περιγεννητικής θνησιμότητας στη σχετικώς αναφερόμενη γεωγραφική περιοχή. Υπάρχει, ωστόσο, σημαντική έλλειψη πρόσφατων επιδημιολογικών δεδομένων για τον ελλαδικό χώρο, τόσο για την επίπτωση και τον επιπολασμό της περιγεννητικής ασφυξίας και της συνεπακόλουθης υποξαιμικής ισχαιμικής εγκεφαλοπάθειας, όσο και για την άμεση και μακροχρόνια εξέλιξη των πασχόντων νεογνών 40,41. Όσον αφορά στην πρόγνωση των νεογνών με υποξαιμική ισχαιμική εγκεφαλοπάθεια γενικότερα, αυτή εξαρτάται σε μεγάλο βαθμό από το μέγεθος της βλάβης και τη σταδιοποίηση της νόσου, δηλαδή ήπια, μέτρια ή σοβαρή.…”