Reddi A S
Department of Medicine, UMDNJ-New Jersey Medical School, Newark 07103.
Exp Mol Pathol. 1988 Apr;48(2):236-43. doi: 10.1016/0014-4800(88)90060-3.
Myocardial collagen and total protein synthesis were studied in normal, diabetic, and insulin-treated diabetic rats after a single intraperitoneal injection of L-[2,3-3H]proline as a radioisotopic precursor. The incorporation of tritiated proline into myocardial protein was regarded as a measure of total protein synthesis and the incorporation into hydroxyproline as indicative of myocardial collagen synthesis. Both total protein and collagen synthesis were found to be significantly lower in diabetic rats. This was associated with decreased degradation of both total protein and collagen in diabetic rats, as suggested by prolonged turnover times. Collagen content was also found to be increased in diabetic myocardium. Early insulin therapy with normalization of blood sugars in diabetic rats returned myocardial collagen metabolism to normal. This suggests that maintenance of euglycemia in diabetic rats is necessary to prevent abnormal myocardial collagen metabolism.
在正常大鼠、糖尿病大鼠以及胰岛素治疗的糖尿病大鼠单次腹腔注射L-[2,3-³H]脯氨酸作为放射性同位素前体后，对其心肌胶原蛋白和总蛋白合成进行了研究。将氚标记的脯氨酸掺入心肌蛋白被视为总蛋白合成的一种度量，而掺入羟脯氨酸则被视为心肌胶原蛋白合成的指标。发现糖尿病大鼠的总蛋白和胶原蛋白合成均显著降低。这与糖尿病大鼠总蛋白和胶原蛋白降解减少有关，周转时间延长表明了这一点。还发现糖尿病心肌中的胶原蛋白含量增加。糖尿病大鼠早期进行胰岛素治疗使血糖恢复正常，心肌胶原蛋白代谢也恢复正常。这表明维持糖尿病大鼠的血糖正常对于预防异常的心肌胶原蛋白代谢是必要的。
