Instituto de Ciencias Ambientales y Evolutivas, Universidad Austral de Chile, Casilla 567, Campus isla teja, Valdivia, 5090000, Chile.
Comp Biochem Physiol A Mol Integr Physiol. 2013 Oct;166(2):338-42. doi: 10.1016/j.cbpa.2013.07.010. Epub 2013 Jul 10.
Seasonal torpor or hibernation is a phenomenon characterized by a physiological transition to dormancy (torpor) during challenging periods in terms of energy availability or metabolic load. Extensive physiological reprogramming and changes in gene-expression, immune function, oxygen transport and intermediate metabolism, occur during eutherian hibernation. Here we studied the seasonality of blood parameters, and during daily torpor, in a South American marsupial (Dromiciops gliroides). Seasonal trends in blood parameters showed an increase in hematological parameters during winter, and increases in total proteins, albumin and globulin during autumn. In contrast, torpor induced a drastic drop during most blood parameters. PCV dropped significantly 60%, as well as RBC (58%), hemoglobin concentration (58%), WBC (79%), including neutrophils (51%), eosinophils (84%) and lymphocytes (82%). Biochemical parameters also showed reductions: triglycerides (81%), proteins (32%), albumin (24%), globulins (38%), albumin (24%), creatinine (48%) and glucose (42%). Our results confirm some patterns observed in hibernating eutherians, such as leukopenia, probably caused by sequestration of white blood cells in organs. However, red blood cells and hemoglobin concentration also were reduced, which is to the best of our knowledge has not been reported for marsupials. The observed reduction in biochemical parameters suggests that marsupials, as in eutherians, change from carbohydrate-based to lipid-based metabolism during hibernation. However, the absence of increases in beta-hydroxybutyrate is puzzling. Finally, we found an increase (although non-significant after statistical correction for multiple comparisons) of creatine kinase which together with an increase in neutrophil/lymphocyte ratio could be indicative of muscle lysis and inflammation. These results indicate profound changes in standard physiological processes during torpor.
季节性蛰伏或冬眠是一种生理现象，表现为在能量供应或代谢负荷方面具有挑战性的时期向休眠（蛰伏）转变。在真兽类冬眠期间，会发生广泛的生理重编程和基因表达、免疫功能、氧气运输和中间代谢的变化。在这里，我们研究了一种南美洲有袋动物（Dromiciops gliroides）的血液参数的季节性变化和日常蛰伏期间的血液参数变化。血液参数的季节性趋势显示，冬季血液学参数增加，秋季总蛋白、白蛋白和球蛋白增加。相比之下，蛰伏会导致大多数血液参数急剧下降。PCV 显著下降 60%，红细胞（RBC）下降 58%，血红蛋白浓度下降 58%，白细胞（WBC）下降 79%，包括中性粒细胞下降 51%，嗜酸性粒细胞下降 84%，淋巴细胞下降 82%。生化参数也显示出降低：甘油三酯（81%）、蛋白质（32%）、白蛋白（24%）、球蛋白（38%）、白蛋白（24%）、肌酐（48%）和葡萄糖（42%）。我们的结果证实了在真兽类冬眠中观察到的一些模式，例如白细胞减少症，可能是由于白细胞在器官中的隔离。然而，红细胞和血红蛋白浓度也降低了，据我们所知，这在有袋动物中尚未报道过。观察到的生化参数降低表明，与真兽类一样，有袋类在冬眠期间从基于碳水化合物的代谢转变为基于脂质的代谢。然而，β-羟丁酸的增加并不明显。最后，我们发现肌酸激酶增加（尽管在经过多次比较的统计校正后无显著性），中性粒细胞/淋巴细胞比值增加，这可能表明肌肉溶解和炎症。这些结果表明在蛰伏期间，标准生理过程发生了深刻变化。
