eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2017-12-21 10 4 1651 1659 10.13005/bpj/1276 18348 article Hyung Lyung Jung 1 Jong Sik Ryu 1 Sang Yeong Kim 1 Young Taek Doo 2 Ho Youl Kang 1 Department of Physical Education, Kyungpook National University, Daegu, Republic of Korea. Department of Physical Therapy, Gwangju Woman’s University, Gwangju, Republic of Korea. We evaluated the effects of low- and high- dosage growth hormone (GH) administration on muscle ceramide contents and insulin resistance in rats. 24 rats were randomly assigned to three groups: low dosage GH injection group (L/GH, n = 8), high dosage GH injection group (H/GH, n = 8) and saline injection group (CON, n = 8). GH groups received GH by subcutaneous injections (L/GH; 65 μg/kg/day, H/GH; 130 μg/kg/day, 6 days/week) for 4 weeks, while CON received saline injections that were equivalent in volume to L/GH group. At the end of 4-week treatments, plasma lipids, insulin and glucose levels were measured.  Glucose transporter 4 protein (GLUT-4) and ceramide contents were determined in muscle while triglyceride contents were determined in both muscle and liver. Rate of glucose uptake was determined under submaximal and non- insulin conditions during the epitrochlearis incubation. After 4 weeks of GH injection, H/GH had significantly higher plasma FFA levels (p < 0.05), but L/GH did not have it compared to CON. Plasma insulin levels were significantly lower in H/GH and glucose level in H/GH was higher than CON group (p < 0.05). Muscle ceramide, muscle and liver triglyceride contents were significantly greater in H/GH than CON, but those were not significantly different between L/GH and CON. Glucose transport rate under submaximal insulin condition was significantly lower in H/GH group than CON group (p < 0.05), but L/GH was not different from CON. Therefore, results of this study suggested that the deterioration of muscle insulin resistance due to GH treatment is strongly associated with the elevated TG and ceramide contents due to high GH administration dosage in rats. https://biomedpharmajournal.org/vol10no4/comparison-of-low-and-high-dose-growth-hormone-administration-on-muscle-ceramide-contents-and-insulin-resistance-in-rats/ Growth Hormone Muscle Triglyceride Liver Triglyceride Ceramide Glucose Transport Rate Insulin Resistance