Objective:To observe the genioglossus fiber type changes in rats of different hypoxia time.Methods:Establishing the
hypobaric hypoxia model, the model was confirmedby blood gas analysis.At different time, the genioglossus was tested by HE staining,
myosin ATP enzyme staining and RT-PCR was detected the changes in muscularfiber types.Results:The blood gas analysis showed that
both partial pressure of oxygen (PO) and oxygen saturation (OS) in the experimental group (hypobaric hypoxia)was significantly
decreased than that of the control group. In hypoxia 1 week, 2 weeks, 3 weeks, 4 weeks groups, the PO was decreased to 55.04± 2.31
mmHg, 52.69± 1.51 mmHg, 49.80± 1.39 mmHg, 50.11± 3.02 mmHg(P<0.05); blood oxygen saturation was decreased to77.51± 1.81%,
70.13± 2.90%,74.20± 1.95%, 74.97± 2.36%(P<0.05). HE staining and myosin ATP enzyme histochemical staining showed that, in
hypoxia 2,3,4-week group, compared with normal group, type Ⅱ fibers was increased by45.92± 1.8%, 57.44± 2.1%, 56.89± 2.6%with
the peak in the third week. RT-PCR results also verified this rule.Conclusion:The genioglossus fiber types changed regularly along with
thehypoxia time which affected the function of muscle. |