Patterns of sudanophilic lesions at ostia of descending thoracic and abdominal aorta in cholesterol-fed adult rabbits / Patrones de lesiones sudanofílicas en el ostio de las partes torácica y abdominal de la aorta en conejos adultos alimentados con colesterol

Sudan-positive atherosclerotic lesions preferentially occur at downstream and lateral margins of arterial branch ostia in human neonates and weanling rabbits but tend to develop at lateral and upstream margins in old subjects. We investigated (i) the pattern of sudanophilic lesions at aortic ostia of cholesterol-fed adult rabbits and (ii) determined any differences in lesion distribution between descending thoracic and abdominal aorta. Ten adult males, New Zealand white rabbits were fed 2 percent high cholesterol diet. After six weeks, aortas were excised, opened longitudinally and stained with Sudan-IV for gross examination of atherosclerotic lesions. A total of 156 descending thoracic and 90 abdominal ostia were examined. Mean lesion frequencies upstream, downstream and at lateral margins of the affected ostia were calculated and compared. Sudanophilic lesions were detected around 32 percent ostia of descending thoracic aorta and 25 percent those of abdominal aorta. At ostia of descending thoracic aorta, lesion frequencies were significantly higher (P<0.001) downstream (95 percent) and at lateral margins (92 percent) than upstream (2 percent). In abdominal aorta, lateral (100 percent) and upstream (43 percent) margins were significantly (P<0.05) more affected while minimal lesion frequencies were seen at downstream branch points (9 percent). Comparison between descending thoracic and abdominal aorta showed an insignificant difference of lesion frequencies at lateral margins (P>0.05) but a highly significant difference at upstream versus downstream of ostia (P<0.001). We concluded that in cholesterol-fed adult rabbits, juvenile pattern of downstream lipid deposition persists at ostia of descending thoracic aorta while a switch towards the upstream pattern of old subjects occurs at ostia of abdominal aorta.

Las lesiones ateroscleróticas Sudán-positivas se producen preferentemente en los márgenes posteriores y laterales del ostio de las ramas arteriales en neonatos humanos y en conejos destetados, pero tienden a desarrollarse en los márgenes laterales y superiores en sujetos de edad avanzada. Investigamos el patrón de lesiones sudanofílicas en el ostio aórtico de conejos adultos alimentados con colesterol y determinamos las diferencias en la distribución de lesiones entre la aorta torácica descendente y abdominal. Diez conejos machos blancos adultos New Zealand fueron alimentados con una dieta alta en colesterol al 2 por ciento. Después de seis semanas, fueron extraídas las aortas, se disecaron longitudinalmente y se tiñeron con Sudan-IV para el examen macroscópico y se observaron las lesiones ateroscleróticas. Fueron examinados 156 ostios de aortas torácicas descendentes y 90 de aortas abdominales. Fueron calculadas y comparadas las frecuencias medias de lesiones superiores, inferiores y de los márgenes laterales de los ostios afectados. Las lesiones sudanofílicas se detectaron en alrededor del 32 por ciento de ostios de la aorta torácica descendente y en el 25 por ciento de las aortas abdominales. En el ostio de la aorta torácica descendente, las frecuencias de lesiones fueron significativamente mayores (p <0,001) por superior (95 por ciento) y en los márgenes laterales (92 por ciento) que por inferior (2 por ciento). En la aorta abdominal, los márgenes laterales (100 por ciento) y superiores (43 por ciento) fueron significativamente más afectados (p <0,05), mientras que las frecuencias mínimas de lesiones se observaron en los puntos de la rama descendente (9 por ciento). La comparación entre la aorta torácica descendente y abdominal mostró una diferencia no significativa de las frecuencias de lesiones en los márgenes laterales (p> 0,05), pero muy significativa al comparar el margen superior con el inferior (p <0,001). Llegamos a la conclusión que en los conej...

Role of beta carotene on histomorphology of liver in acetaminophen-induced hepatotoxicity in rats

To study the protective role of beta carotene against acetaminophen-induced hepatotoxicity in rats. Laboratory based randomized control trial. Department of Anatomy Army Medical College, Rawalpindi; in collaboration with National Institute of Health [NIH], Islamabad. The study duration was one year from Feb, 2009 to Jan, 2010. Sixty young adult [4-6 weeks old] Sprague-Dawley rats weighing 180-240 g were randomized into three groups. Control group C was given NIH laboratory diet, experimental group A was given toxic dose of acetaminophen 700 mg/kg body weight once daily and experimental group B was given beta carotene 30 mg/kg body weight once daily along with 700 mg/kg body weight acetaminophen once daily for one week. Liver specimens were collected 24 hours after the last dose. Five micron thick sections of liver were stained with H and E for histomorphological study. Microscopic examination demonstrated various grades of periportal and spotty necrosis in experimental group A as compared to control group C. In experimental group B, there was significant attenuation [P-value < 0.001] in periportal and spotty necrosis. It was concluded that beta carotene has hepatoprotective role on histomorphology of liver in acetaminophen-induced hepatotoxicity in rats