視丘下部의 血糖代謝에 미치는 影響에 關한 實驗的 硏究 = Influences of hypothalamus on the blood glucose metabolism

다국어 초록 (Multilingual Abstract)

Anchner observed glucosuria in the dog after lesions of floor of Ⅲ. ventricle, and Sachs & McDonald also observed transient hyperglycemia following hypothalamic puncture. Himwich observed hyperglycemia in cat, anesthetized with amythal following electric stimulation in hypothalamus. Lewy & Gassman observed hyperglycemia in cat following stimulation of paraventricular nucleus. Baily, Bremer and D'amour, Keller observed transient glycosuria and hyglycemia following hypothalamic lesion respectively. Barris & Ingram reported that transient hyperglycemia or hypoglycemia appear after electric lesion of hypothalmiamus. Contrary, Keller, Noble & Keller et al experienced hypoglycemia following hypothalamic lesion in most cases.
We would say, after reviewing above studies, there is close relationship between glucose metabolism and hypothalamus. Unfortunately there is no any agreement each other so far. Above studies were done by electric stimulation, electrolytic lesion or puncture methods etc.
In order to investigate whether hypothalamus concerns blood glucose homeostasis or not, authors observed blood glucose level following injection of concentrated glucose solution in various area of hypothalamus directly in rabbits.
1.8 kg of body weight Korean white male rabbits were used and fed bean-curd refuse. The rabbit were fast for from 12 hours to 16 hours before experiments. We chose 30 gauge injection needle in order to prevent stimulation locally as much possible into the hypothalamus. Injection area were determined according to stereotaxic coordinates which was studied by 1.S. Choi. Solution of 0.05 c.c were injected bilaterally by stereotaxic apparatus.
Solution of injection are 20% pure glucose solution and physiologic saline solution. According to Somogyi-Nelson micromethod, blood glucose are determined.
The results were as follows.
1) 10 rabbits were used for simple injection whit 30 gauge needle in anterior, middle and posterior parts of hypothalamus. There not any significant changes except hypoglycemia in 2 cases, hyperglycemia in 1 case following injection of needles respectively.
2) When physiologic saline solution were injected in anterior hypothalamus in 7 rabbits, blood glucose level revealed rapid and marked rise 15 min., rapid decline 30 minutes, and regained normal level 90 minutes after injection.
3) When 20% glucose solution were injected in anterior hypothalamus in 11 rabbits, blood glucose level declined rapidly and inarkedly after 15 min. whereas 30 minutes later increased rapidly and kept higher blood glucose level continuously than fasting blood level.
4) When physiologic asline solution were injected in middle hypothalamus in 5 rabbits, blood glucose level rised markedly 15 minutes later and then declined slowly but still kept somewhat higher level of blood glucose than fasting level.
5) When 20% glucose solution were injected in middle hypoothalamus in 5 rabbits, blood glucoselevel rised slighty after 30 minutes and then declined slowly. 90 minutes later blood glucose level regained almost to the fasting level.
6) When physiologic saline solution were injected in posterior hypothalamus in 5 rabbits, blood glucose level rised slightly 15 minutes later and then slowly declined to fasting blood glucose level 90 minutes later.
7) When 20% glucose solution were injected in posterior hypothalamus in 5 rabbits, blood glucose level rised slightly 30 min. later and declined to fasting level 90 minutes later.
8) We can conclude above results as follows. Folowing injection of physiologic saline solution or 20% glucose solution in middle and posterior area of hypothalamus, blood glucose amount increased through there are some differences in its rapidity and degree. Against these results, as the physiologic saline solution was injected in anterior hypothalamus, the rabbit blood glucose level increased rapidlyand markedly, and then declined rapidly. Contrary, as the 20% glucose solutions were injected in the same area, it declined rapidly and then increased, followed by the higher blood glucose level continuously than fasting level.
Therefore we assume that temporary rise of rabbit blood glucose level following injection of physiologic saline solution or 20% glucose solution in middle and posterior hypothalmus might be due to the stimulation of injection itself. But the tendency toward opposite direction of blood glucose level following injection of physiologic saline solution and 20% glucose solution in anterior hypothalamus indicates that anterior hypothalamus posses the function of "glucoreceptor" or "chemoreceptor" in broad sense.