Evidence of reduced atherosclerotic lesions in broad breasted white turkeys treated with oxprenolol.

Male Broad Breasted White Turkeys (BBWT) are naturally hypertensive and prone to develop atherosclerosis. Hypertension is characterized by high levels of circulating and tissue catecholamines; atherosclerosis affects mainly the aorto-iliac tract. To evaluate the effect of a beta-blocker on both hypertension and atherosclerosis, 2 groups of BBWT were studied. First group: 12 BBWT treated from the 8th week of age with daily p.o. placebo; second group: 6BBWT treated from the 8th week with 2 mg/kg p.o. daily oxprenolol. Blood pressure (BP) and heart rate (HR) were periodically measured with an indirect method. Seven and 5 BBWT of the first group were sacrificed at 24 and 51 weeks respectively. The 6 animals of the second group were sacrificed at 51 weeks. No significant difference in mean BP and HR values was found between the two groups of animals. On the contrary the oxprenolol treated group displayed a significant reduction in extent and severity of the atherosclerotic lesions. These results seem to substantiate that oxprenolol might positively interfere with the setting of atherosclerosis in these animals independently of BP reduction. One possible explanation could be a direct effect of oxprenolol on the arterial wall.