1H-MRS detected lipolysis in diabetic rat hearts requires neutral lipase.
1H-MRS detected lipolysis in diabetic rat hearts requires neutral lipase.
复制标题
1H-MRS检测到糖尿病大鼠心脏中的脂肪分解需要中性脂肪酶。
DOI：
10.1081/jcmr-100000141
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
Wolkowicz,P
中科院分区：
文献类型：
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作者：
Shen,H;Balschi,JA;Pohost,GM;Wolkowicz,P
目的糖尿病心脏中三酰甘油 (TAG) 脂肪分解增加。然而，尚不清楚哪条脂肪分解途径催化了这一过程。因此，我们利用 1 H 磁共振波谱 (MRS) 确定了糖尿病大鼠心脏中的 TAG 脂肪分解是否需要酸性脂肪酶或中性脂肪酶活性。方法给大鼠腹腔注射 110 mg 链脲佐菌素 (STZ)/kg。治疗后 48 至 72 小时，所有大鼠均表现出酮症糖尿病。分离这些酮症大鼠的心脏，进行等容灌注，并使用 1 H-MRS 进行分析。结果使用 1 H-MRS 测量，与未治疗的大鼠相比，从 STZ 治疗的大鼠分离的心脏中亚甲基质子 (CH2)n- 和其他脂肪酸质子的含量有所增加。心脏 -(CH2)n- 的增加与心脏 TAG 的化学含量直接相关。如果用葡萄糖或葡萄糖加酸性脂肪酶抑制剂甲胺灌注离体糖尿病心脏，则心脏的 TAG 含量（以 (CH2)n 测量）在整个 55 分钟灌注过程中以大约 130 nmol TAG/gdw/min 的速率下降。如果用中性脂肪酶抑制剂二乙基对硝基苯磷酸酯（DNPP）预处理糖尿病心脏并灌注葡萄糖，则心脏TAG含量（以（CH2）n测量）在灌注过程中没有变化。结论 1H-MRS可以检测糖尿病大鼠心脏中的TAG和TAG的净脂解。糖尿病大鼠心脏中的净 TAG 脂肪分解需要中性脂肪酶。
PurposeTriacylglycerol (TAG) lipolysis increases in diabetic hearts. However, it is not known which pathway for lipolysis catalyzes this process. Thus, using1H-magnetic resonance spectroscopy (MRS), we determined whether TAG lipolysis in diabetic rat hearts requires acid lipase or neutral lipase activity.MethodsRats were given IP injections of 110 mg streptozotocin (STZ)/kg. Forty-eight to 72 h after this treatment, all rats exhibited ketotic diabetes. The hearts of these ketotic rats were isolated, perfused isovolumically, and analyzed using1H-MRS.ResultsThe content of methylene protons (CH2)n- and other fatty acid protons, measured using1H-MRS, increased in hearts isolated from STZ-treated compared to untreated rats. This increase in heart −(CH2)n− was directly related to the chemical content of heart TAGs. If isolated diabetic hearts were perfused with either glucose or glucose plus the acid lipase inhibitor methylamine, then heart content of TAG, measured as (CH2)n, decreased at rates of approximately 130 nmol TAG/gdw/min throughout a 55-min perfusion. If diabetic hearts were pretreated with the neutral lipase inhibitor diethyl-p-nitro-phenylphosphate (DNPP) and perfused with glucose, then heart TAG content, measured as (CH2)n, did not change during perfusion.Conclusions1H-MRS can detect the TAG and the net lipolysis of TAG in diabetic rat hearts. Net TAG lipolysis in diabetic rat hearts requires neutral lipase.