Sartin J L, Lamperti A A, Kemppainen R J
Endocr Res. 1985;11(3-4):145-55. doi: 10.1080/07435808509032973.
This study was performed to determine the effects of monosodium glutamate (MSG) induced lesions of the hypothalamic arcuate nucleus (ARC) on glucose tolerance and insulin and glucagon secretion in male golden hamsters. Eight day old hamsters were given a single s.c. injection of 5.8 mg/g BW MSG or hypertonic saline (controls). Studies were initiated when the hamsters were 3 months of age. At this age there were no body weight differences. Glucose (180 mg/100 g BW) was administered via stomach tube to 18 control and 18 MSG-treated hamsters. Animals were anesthetized with ether and a single blood sample from the portal vein was taken either before or at 30 or 60 min after glucose administration (n = 6/group). Glucose concentrations were similar in both groups at all time periods. Insulin concentrations in the MSG group were significantly (P less than 0.05) elevated in MSG-treated hamsters compared to controls at the 60 min time point. Glucose suppressed glucagon (P less than 0.05) in control but not in MSG-treated hamsters. The MSG group had significantly more glucagon (P less than 0.05) in portal vein blood at 30 min after glucose administration than did the control hamsters. Molar insulin/glucagon ratios did not differ between the 2 groups which likely accounts for the lack of differences in blood glucose levels. These results suggest a role for the ARC in regulating pancreatic function.
本研究旨在确定谷氨酸钠（MSG）诱导的雄性金黄地鼠下丘脑弓状核（ARC）损伤对葡萄糖耐量以及胰岛素和胰高血糖素分泌的影响。给8日龄的地鼠单次皮下注射5.8 mg/g体重的MSG或高渗盐水（对照组）。在地鼠3月龄时开始研究。此时两组地鼠体重无差异。通过胃管给18只对照地鼠和18只经MSG处理的地鼠给予葡萄糖（180 mg/100 g体重）。用乙醚麻醉动物，在给予葡萄糖之前、之后30或60分钟采集门静脉血样（每组n = 6）。所有时间段两组的葡萄糖浓度相似。在60分钟时间点，与对照组相比，经MSG处理的地鼠MSG组的胰岛素浓度显著升高（P < 0.05）。葡萄糖抑制对照组的胰高血糖素（P < 0.05），但不抑制经MSG处理的地鼠的胰高血糖素。在给予葡萄糖后30分钟，MSG组门静脉血中的胰高血糖素显著多于对照地鼠（P < 0.05）。两组之间的胰岛素/胰高血糖素摩尔比无差异，这可能是血糖水平无差异的原因。这些结果表明ARC在调节胰腺功能中起作用。
