Effects Of Changbai Mountain Radix Astragali On Skeletal Muscle Contration Force And Its Mechanism In Mice And Rats

[Objective] To investigate effects and its biochemical mechanism of Changbai Mountain Radix Astragali Aqueous extract on skeletal muscle contratility.[Methods] Kunming mice and Wistar rats were used. The swimming time and superoxide dismutase (SOD) activity and malondialdehyde (MDA)content were dertermined in mice. To determine the skeletal muscle myotility and activity of superoxide dismutase (SOD) and content of malondialdehyde (MDA) in rat. Aiming to aqueous extract, forty mice will be selected from fifty mice then random divided into four groups(control group, Changbai Mountain Radix Astragali aqueous extract low dose group,middle dose group and large dose group). It is ten in every group. The dose of Changbai Mountain Radix Astragali extract will be intragastric administration according to correspondent crude drug(low dose 3g/kg,middle dose 12g/kg, large dose 24g/kg). The control group will be administrated by physiological saline. The loading swimming time will be determined after intragastric administration one hour in 21day. Then, the blood were obtained by extirpating eyeball in mice. SOD and MDA were determined by centrifuging the blood. Forty male Wistar rats will be random devided into four groups:control group ( tales doses Sodium Chloride ), aqueous extract low dose group (1.5g/kg), middle dose group(6.0g/kg), large dose group 12.0g/kg). It is ten in every group. To determine the skeletal muscle myotility and activity of superoxide dismutase (SOD) and content of malondialdehyde (MDA) in rat after intragastric administration one hour in 21day.[Results] 1.Effects of Changbai Mountain Radix Astragali aqueous extract on loading swimming time and weight in mice: After intragastric administration three weeks with Changbai Mountain Radix Astragali aqueous extract in mice, the loading swimming time significantly prolongated in middle dose group and large dose group compaired with control group (P<0.05);â‘¡Only the large dose group's mice weight lessen compaired with control group(P<0.05). 2. Effects of Changbai Mountain Radix Astragali aqueous extract on skeletal muscle myotility: Radix Astragali aqueous extract with middle dose and large dose can enhance Pt, prolong CT and HRT during the gastrocnemius muscle's twitch take place, enhance Pt, shorten CT and HRT when the soleus muscle's simple contraction take place, and enhance Pt , diminish FI when the gastrocnemius and soleus muscle's tetanus take place compaired with control group in rat (P<0.05); 3. Effects of Changbai Mountain Radix Astragali aqueous extract on SOD and MDA :â‘ Effects of Changbai Mountain Radix Astragali aqueous extract on SOD and MDA in serum of mice: Aqueous extract with middle dose and large dose can increase SOD compaired with control group (P<0.05); Aqueous extract with low dose and middle dose can significant degrade MDA compaired with control group (P<0.05);â‘¡Effects of Changbai Mountain Radix Astragali aqueous extract on SOD and MDA in skeletal muscle of rats: Aqueous extract with middle dose and large dose can significant increase SOD and degrade MDA compaired with control group in either gastrocnemius muscle or soleus muscle (P<0.05).[Conclusion] 1. Aqueous extract of Changbai Mountain Radix Astragali plays an important role in anti-fatigue and has a dose-effect relationship. 2. Changbai Mountain Radix Astragali can raise skeletal muscle's contractibility. 3. Changbai Mountain Radix Astragali can raise the activity of SOD, and can inhibit lipid peroxidation in blood and skeletal muscle tissue. It's possible that Changbai Mountain Radix Astragali via enhancing anti-free radical in blood and skeletal muscle to achieving anti-fatigue effects.