Prostaglandin Metabolism in Diabetics with Muscular Exercise

Abstract

Recent reports have indicated that prostaglandins (PGs) play an important role in the secretion of insulin and other hormones.From this viewpoint, changes in PGs, insulin, and counter-regulatory hormones were investigated in 6 cases of IDDM, 8 cases of NIDDM, and 7 normal subjects.They underwent 3 stages of graded muscular exercise with a bicycle ergometer.Blood samples were taken 5 times from the cubital vein (the before, at 15 min, 30 min, 45 min, 60 min), and plasma immunoreactive PGE-like material (iPGE), immunoreactive 6-keto-PGF1-like material (i-6-keto-PGF_1α), blood sugar, IRI, IRG, HGH, and cortisol levels were measured.PGs were assayed by RIA, The results obtained were as follows.1) The plasma iPGE levels were significantly decreased with muscular exercise in the normal subjects and IDDM patients.2) The plasma i-6-keto-PGF_1α, levels were significantly decreased with muscular exercise in the normal subjects and NIDDM patients. 3) The blood sugar values were significantly depressed in all groups with muscular exercise.The IRI levels were significantly decreased in the normal subjects with muscular exercise.The IRG levels were significantyl decreased in the NIDDM patients with muscular exercise.The cortisol levels were significantly decreased in NIDDM with muscular exercise.The HGH levels were significantly elevated with muscular exercise only in the NIDDM patients.
These results suggested PGs metabolic abnormalities in diabetics, and that the abnormalities might be related to some of the counter-regulatory hormones.