Pathophysiologic responses of spontaneously hypertensive rats to arterial magnesium--aluminum wire implants

Magnesium--aluminum (Mg--Al) alloy wire was surgically implanted in the abdominal aorta and carotid and renal arteries of virgin (no arterial disease) and breeder (testicular and ovarian arterial lesions) spontaneously hypertensive rats (SHR). The Mg--Al implants promptly dissolved causing increased adrenal glandular weight, thymic involution, depression of the abnormally elevated blood pressure, and poor growth. Serum enzymes (CPK, SGOT, SGPT and LDH) were elevated, circulating levels of triglycerides and cholesterol were reduced, corticosterone and deoxycorticosterone secretion increased. Histologically, fibrocellular, intimal lesions, rich in ground substance, developed about the Mg-Al implants. Occlusive thromboses with cholesterol-positive clefts appeared in the Mg-Al-implanted carotid arteries of breeder SHR with preexisting arterial (limited to gonadal arterioles) disease. It is suggested that adrenocortical and gonadal hormonal factors may condition the responsiveness of the arterial wall of SHR to injury and repair.