MEAL PATTERNS AND MACRONUTRIENT INTAKE AFTER PERIPHERAL AND PVN INJECTIONS OF THE ALPHA(2)-RECEPTOR ANTAGONIST IDAZOXAN
MEAL PATTERNS AND MACRONUTRIENT INTAKE AFTER PERIPHERAL AND PVN INJECTIONS OF THE ALPHA(2)-RECEPTOR ANTAGONIST IDAZOXAN
复制标题
DOI：
10.1016/0031-9384(93)90165-c
复制
发表时间：
1993-04-01
影响因子：
2.9
通讯作者：
LEIBOWITZ, SF
中科院分区：
文献类型：
--
作者：
ALEXANDER, JT;CHEUNG, WK;LEIBOWITZ, SF
特定 α2 去甲肾上腺素受体拮抗剂咪唑克生 (IDA) 的研究表明，其对进食行为的影响与室旁核 (PVN) 中去甲肾上腺素和外周注射 α2 激动剂可乐定所观察到的效果相反。在夜间进食周期开始时，通过腹膜内 (IP) 和 PVN 注射 IDA。注射后 90 分钟引起剂量相关的选择性碳水化合物摄入抑制。为了进一步表征这种拮抗剂对常量营养素摄入的影响，我们使用计算机辅助膳食模式分析来检查注射 IDA 的动物的摄食宏观结构。 IP 和 PVN 施用 IDA 都会选择性抑制碳水化合物的摄入，主要是在喂养周期的第一餐期间。这种效应是通过显着减少膳食量、饮食成分、喂养时间和这种营养素的喂养率来实现的。向 PVN 施用咪唑克生继续减少接下来两餐中碳水化合物的摄入量，并降低了这种营养素的饱腹感。与碳水化合物摄入量的这种立即变化相反。 PVN IDA 在潜伏 4 小时后减少了蛋白质摄入，但脂肪摄入仅在潜伏 7 小时后受到抑制。施用 PVN IDA 后，在 12 小时黑暗周期中，总进餐次数增加，平均进餐量减少。这些结果显示了外周注射 IDA 和 PVN 注射的 IDA 对碳水化合物摄入量的影响。表明内源性 PVN α2-去甲肾上腺素受体在调节黑暗期开始时碳水化合物进食的自然模式中可能发挥生理作用。
Studies with idazoxan (IDA), a specific alpha2-noradrenergic receptor antagonist, demonstrate effects on feeding behavior opposite to those observed with norepinephrine in the paraventricular nucleus (PVN) and peripheral injection of the alpha2 agonist clonidine. Administration of IDA, both intraperitoneally (IP) and into the PVN at the onset of the nocturnal feeding cycle. caused a dose-related, selective suppression of carbohydrate intake 90 min after injection. To characterize further the impact of this antagonist on macronutrient intake, we examined in IDA-injected animals the macrostructure of feeding using computer-assisted analyses of meal patterns. Both IP and PVN administration of IDA produced a selective suppression of carbohydrate intake, primarily during the first meal of the feeding cycle. This effect occurred through significant reductions in meal size, diet composition, feeding time, and feeding rate for this nutrient. Idazoxan administration into the PVN continued to decrease carbohydrate intake in the next two meals and reduced the satiating impact of this nutrient. In contrast to this immediate change in carbohydrate intake. PVN IDA reduced protein intake after a latency of 4 h, although fat intake was suppressed only after a latency of 7 h. An increase in total meal number and a decrease in the average meal size across the 12-h dark cycle were seen after PVN IDA administration. These results, showing effects of peripheral and PVN-injected IDA on carbohydrate intake. suggest a possible physiological role of endogenous PVN alpha2-noradrenergic receptors in modulating natural patterns of carbohydrate feeding at the onset of the dark period.