Different Frequency Electric Late Pregnant Rat Uterine Contractile Activity And Its Mechanism

At the present the diseases of prolonged pregnancy, difficult labor and high riskpregnancy are still the main factors affected security of mother and baby, so promotinglabor should be used in those cases. Promoting labor includes two aspects of inducinglabor and hastening labor. The common methods of promoting labor in the clinic arepharmacotherapy, mechanotherapy, cesarean section and so on, which always inducesome side-effect. Therefore, seeking more safe, convenient and effective methods forpromoting labor is an urgent task of obstetrics. Hegu (LI4) and Sanyinjiao (SP6) is a classical pair-points for promoting laborwith highest usage frequency. Clinical studies indicate applying electric acupuncture toLI4 and SP6 can strengthen the effect of acupuncture to promoting labor. Acupuncturetechnique is an important factor to affect the curative effect. The electric acupuncturesimulates acupuncture manual techniques through changing the parameter, whichincludes wave, amplitude, frequency and duration. The early experimental researchindicated that interval between LI4 and SP6 and the different duration result indifferent effect of promoting labor, so the electric acupuncture parameter can influencethe acupuncture effect. The former research approved the frequency is the keyparameter of electric acupuncture, because the different frequency has the differentmechanism and brings out different effect. Therefore, based on the former research,this experiment aimed at seeking the best electric acupuncture frequency on points forpromoting labor through comparing the influence on uterine contraction and endocrinesystem caused by different frequency, in order to provide scientific evidence forchoosing the best electric acupuncture frequency for promoting labor in the clinic. Healthy grown-up female Wistar rats were the study objects, while electricacupuncture was the stimulate method. Sixty rats were randomly divided into sixgroups: normal control group, pregnant control group, 2Hz group, 20Hz group, 50Hzgroup and 100Hz group. Needling LI4 20min firstly, then needling SP6 5minafterwards. The values of intensity, frequency and potency of uterine contraction andthe contents of serum E2, P, TXB2,6-K-PGF and ratio of E2 and P , ratio of TXB2 and 6-K-PGF were measured. The results were as follows: 1. In 20min after removing needles, there was no significant difference of uterinecontraction frequency among four electric acupuncture groups, while significantdifference of intensity and potency of uterine contraction was found. The intensity andpotency of uterine contraction in 50Hz group were significantly higher than those inother three groups among which there were no significant difference of intensity andpotency of uterine contraction. 2. Four frequencies of electric acupuncture could all strengthen uterine4 不同频率电针对晚孕大鼠子宫收缩活动及其机制的研究contraction frequency, while its caused different influence on intensity and potency ofuterine contraction. In 50Hz group, the intensity and potency of uterine contractionwere strengthened after needling. The intensity of uterine contraction in 2Hz and 20Hzgroups were decreased after needling, while there was no change of uterine contractionpotency in those two groups. The intensity and potency of uterine contraction in 100Hzgroup were decreased after needling. 3.When 50Hz electric acupuncture was applied on LI4, the uterine contractionwas increased, but it was decreased after needling SP6 and strengthened again after theremoval of needles. Contrarily when 100Hz electric acupuncture was applied on LI4the uterine contraction was decreased, while it was increased after needling SP6 anddecreased again after the removal of needles. It indicates the uterine contraction couldbe strengthened by applying 50Hz electric acupuncture on LI4 and 100Hz on SP6,while it could be weakened by applying 50Hz electric acupuncture to SP6 and 100Hz...