关键词: 巴戟天, 运动行为, 骨骼肌, 收缩张力, 应激

Abstract:

Objective： To investigate the impact of Morinda officinalis on the locomotor capabilities of rats and to elucidate the associated physiological mechanisms.Methods： Fourteen healthy adult Sprague-Dawley （SD） rats were randomly divided into the Morinda group （n=8） and the control group （n=6）. The Morinda group was fed the diet containing Morinda officinalis by natural feeding method， while the diet of the control group did not contain Morinda officinalis. Behavioral assessments were conducted at baseline （W0）， and after 4 weeks （W4） and 8 weeks （W8） of the feeding. The behavioral assessments included tests for basic motor behavior （gait analysis） and challenging motor tasks （suspension and shaking-rod tests）. After the behavioral tests， sciatic nerve-gastrocnemius specimens were prepared in vivo，skeletal muscle contraction waves were recorded and analyzed following single electrical stimulation to one side of the sciatic nerve， and the fatigue curves were constructed from continuous electrical stimuli on the another side of the sciatic nerve to evaluate the effect of Morinda officinalis on the contractility of skeletal muscle. Then the gastrocnemiust issue was sectioned to examine the effects of Morinda officinalis on the morphology of muscle fibers.Results： Compared with the control group，there was no significant change in basic motor ability of rats in the Morinda group， but demonstrated significant increase in locomotor capabilities under the stress conditions. Muscle contractions in response to single stimulations did not differ significantly between the two groups， yet the fatigue curve recorded by continuous electrical stimulation showed a notable improvement in muscular endurance of rats in the Morinda group. Additionally， the cross section of muscle fibers of rats in the Morinda group increased significantly compared to the control group.Conclusion： Morinda officinalis enhances locomotor abilities in rats under challenging conditions，which are potentially related to increased skeletal muscular contraction endurance and thickening of muscle fibers. The results of this study offer a scientific basis for further pharmacological research and the development of functional products based on Morinda officinalis.

Key words: Morinda officinalis； , Locomotor behavior； , Skeletal muscle； , Contraction tension； , Stress