Minoru Irie

Effect of nicotinic acid administration on plasma growth hormone concentrations.

Summary Serial plasma glucose, NEFA, and HGH concentrations were measured in normal male subjects following saline injection (Group 1, 9 cases), nicotinic acid injection (Group 2, 5 cases), and nicotinic acid plus heparin injection (Group 3, 4 cases) for 180 minutes. There was no appreciable change of plasma glucose in all groups. In Group 1 there was no significant change of plasma, NEFA and HGH. In Group 2, plasma NEFA showed an initial decrease followed by the secondary rise at 180 minutes, and plasma HGH showed a marked rise at 120 minutes and/or at 180 minutes. In Group 3, plasma NEFA did not show significant reduction and plasma HGH showed no significant changes. From the results obtained, it was suggested that the lowering of plasma NEFA levels by nicotinic acid administration can stimulate the secretion of HGH, and an assumption was made that plasma NEFA could be at least one of the factors in regulating HGH secretion. It was also suggested that plasma HGH may, at least in part, participate in inducing the secondary rise of plasma NEFA following the injection of nicotinic acid.

Effect of Heparin Administration on Plasma Growth-Hormone Concentrations

Summary Plasma HGH, FFA, glucose, and a-amino nitrogen levels were determined in seven young men after heparin administration. Plasma FFA increased rapidly, followed by a gradual fall. Corresponding to the fall of plasma FFA, a marked rise of plasma HGH was demonstrated. This HGH rise was diminished when plasma FFA was kept elevated, or when glucose was given. From these results it was concluded that the fall of plasma FFA could stimulate HGH secretion as in the case of falling blood glucose values and that the fluctuation of plasma FFA could be one of the factors regulating the secretion of HGH. The authors express their thanks to Prof. Kiku Nakao and Dr. Kazuo Shizume (Chief, Dept. of Endocrinology, Toranomon Hospital, Akasaka, Tokyo) for their advice and encouragement. Technical assistance of Miss Junko Shibazaki and Miss Miki Komiyama is greatly appreciated.

Effect of Nicotinic Acid Administration on Plasma HGH, FFA and Glucose in Obese Subjects and in Hypopituitary Patients

Abstract The administration of nicotinic acid in normal subjects caused an acute reduction of plasma FFA followed by a marked progressive secondary rise. Plasma HGH showed a significant rise following the reduction of plasma FFA. Obese subjects displayed a more pronounced reduction and rapid rise of plasma FFA than did normal subjects, but plasma FFA then decreased gradually after it reached its maximum level. There was no significant change of plasma HGH. In hypopituitary patients, the secondary rise of plasma FFA was slow and diminished, and no increase of plasma HGH was observed. From these results, it appears that the late rebound of plasma FFA following nicotinic acid administration is at least partly related to the augmented secretion of HGH. The early and rapid rebound of plasma FFA in obese subjects does not depend on the effect of HGH, but the diminished secretion of HGH might be related to the decrease of lipolysis in these subjects.

SECRETION OF HUMAN GROWTH HORMONE DURING INSULIN COMA AND ELECTROSHOCK THERAPIES

The responses of plasma HGH during psychiatric shock therapies were investigated, and the mechanisms of HGH secretion and of shock therapies were discussed.

Effect of Acute Glucose Infusion on Plasma Concentrations of Human Growth Hormone (HGH).

Summary Serial plasma HGH concentrations were measured, in 18 normal subjects, following continuous intravenous glucose infusion performed for periods of 3, 10, 20 and 30 minutes. In 5 of 8 cases infused for 3 minutes, no rise of plasma HGH was observed in spite of the rapid fall of blood glucose with (4 cases) or without (1 case) its reduction below the fasting level. The 3 other cases infused for 3 minutes and all 10 cases of 10, 20 and 30 minutesinfusion showed definite rise of plasma HGH at 90-180 minutes following the infusion. From the results obtained, it appears that the falling blood glucose per se is not a direct stimulus, and the reduction of blood glucose below the fasting level is not necessarily a stimulus to HGH secretion.