INCREASED GLUCONEOGENESIS IN RATS EXPOSED TO HYPER-G STRESS
INCREASED GLUCONEOGENESIS IN RATS EXPOSED TO HYPER-G STRESS
复制标题
DOI：
10.1016/0024-3205(85)90649-6
复制
发表时间：
1985-01-01
期刊：
影响因子：
6.1
通讯作者：
HANNAK, K
中科院分区：
文献类型：
--
作者：
DALIGCON, BC;OYAMA, J;HANNAK, K
测定了高G（径向加速度）应激大鼠血浆葡萄糖和肝糖原增加的作用。将禁食过夜的雄性Sprague-Dawley大鼠（250-300 g）腹膜内注射均匀标记的14 C乳酸盐、丙氨酸或甘油（5 μ Ci/大鼠），并立即暴露于3.1G 0.25、0.50和1.0小时。测量标记底物掺入血浆葡萄糖和肝糖原的14 C，并与以类似方式注射的未离心对照大鼠进行比较。在所有暴露时间段，在离心大鼠中观察到所有3种标记底物向血糖中的14 C掺入显着增加;仅在0.50和1.0 h时，向肝糖元中的14 C掺入显着增加。在离心前腹膜内给予（5 mg/100 g体重）5-甲氧基吲哚-2-羧酸（一种有效的新生血管生成抑制剂）可阻断离心前1小时内血糖和肝糖原的增加。肾上腺去髓质大鼠离心1.0小时后，血糖和肝糖原的升高也消失。普萘洛尔，A β-肾上腺素能受体阻滞剂可抑制离心0.24 h大鼠的血糖升高。显然，暴露于高G应激的大鼠的血浆葡萄糖的初始快速升高以及肝糖原的增加可归因于血管生成速率的增加，肾上腺素显然在暴露于离心的早期阶段起主导作用。
The role of gluconeogenesis on the increase in plasma glucose and liver glycogen of rats exposed to hyper-G (radial acceleration) stress was determined. Overnight-fasted, male Sprague-Dawley rats (250-300 g) were injected i.p. with uniformly labeled 14C lactate, alanine or glycerol (5 .mu.Ci/rat) and immediately exposed to 3.1G for 0.25, 0.50 and 1.0 h. 14C incorporation of the labeled substrates into plasma glucose and liver glycogen was measured and compared to noncentrifuged control rats injected in a similar manner. Significant increases in 14C incorporation of all 3 labeled substrates into plasma glucose was observed in centrifuged rats at all exposure periods; 14C incorporation into liver glycogen was significantly increased only at 0.50 and 1.0 h. The i.p. administration (5 mg/100-g body wt) of 5-methoxyindole-2-carboxylic acid, a potent gluconeogenesis inhibitor, prior to centrifugation blocked the increase in plasma glucose and liver glycogen during the 1st h of centrifugation. The increase in plasma glucose and liver glycogen was also abolished in adrenodemedullated rats exposed to centrifugation for 1.0 h. Propranolol, a .beta.-adrenergic blocker, suppressed the increase in plasma glucose of rats exposed to centrifugation for 0.24 h. Apparently, the initial, rapid rise in plasma glucose as well as the increase in liver glycogen of rats exposed to hyper-G stress can be attributed to an increased rate of gluconeogenesis, epinephrine evidently, plays a dominant role during the early stages of exposure to centrifugation.