engleski

Lipid changes in frog (Pelophylax ridibundus) during arousal from prolonged hypothermia

Studies on endothermic animals showed that lipid metabolism plays an important role in hibernating animals as main source of metabolic fuel during bouts, contrary to normometabolic states in which glucose metabolism is a main energy source. Data on changes of liver and serum lipid levels in hibernating ectotherms is scarce. Frogs are excellent model for studies of hypometabolic changes in hibernating ectothermic animals. We present the analysis of the dynamics of lipid changes in frogs (Pelophylax ridibundus) exposed to 8°C for 30 days after which they were gradually acclimatized to temperature of 23°C over the period of 24 h, as an artificial induced arousal from hibernation. The entire procedure was recorded using IR camera due to exact temperature measurement during first 148 minutes to establish the exact termal changes of body parts. Species was confirmed by RFLP analysis. Frogs (N=4/time group) were sacrificed immediately after taking them out of hibernaculum, after 1, 2, 4 and 24 hours. Liver lipids were analyzed by TL chromatography. Blood serum lipid (triglycerides, cholesterol, HDL, LDL) levels were analyzed to establish the correlation changes between liver and serum lipid levels at each sampled group. Results showed that temperature rise and arousal from induced hibernation is in correlation with liver lipid mobilization, but on the contrary serum lipids changes have different dynamics within 24 hours.

Pelophylax; hibernation; lipids; serum; liver

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