[Electroacupuncture at "Baihui"（GV20） and "Yongquan"（KI1） improves learning-memory ability of APP/PS1 double transgenic mice by regulating endosomal-lysosomal system]

OBJECTIVE

To explore the mechanism of electroacupuncture（EA） in improving learning-memory ability in Alzheimer's disease （AD） mice from the perspective of endosomal-lysosomal system.

METHODS

Male APP/PS1 transgenic mice were randomly divided into model group and EA group （n=10 in each group） and 10 male C57BL/6 wild mice were taken as the normal group. EA （1 Hz/50 Hz, 1 mA） was applied at bilateral "Yongquan"（KI1） and acupuncture was applied at "Baihui" （GV20） for 15 min. The mice of the model and normal groups were subjected to restriction with the same method as those of the EA group for 15 min. The treatment was conducted once every other day for 6 weeks. The spatial learning-memory ability （shown by escape latency of place navigation test and the time of crossing the target platform and total swimming distance in the target quadrant in 1 min of spatial probe test ） was detected by Morris water maze test. The immunoactivity of senile plaques （SP） in the hippocampus tissue was detected by immunohistochemistry. The ultrastructural characters of hippocampal neurons were observed by transmission electron microscope, and the expression levels of Ras-related protein 5 （Rab5）, Ras-related protein 7 （Rab7） and cathepsin D （CTSD） in the hippocampus were detected by Western blot, separately.

RESULTS

Compared with the normal group, the escape latency, SP immunoactivity, and protein expression levels of Rab5, Rab7 and CTSD were significantly increased （P<0.05, P<0.01）, while the number of crossing the original platform and the total swimming distance in the platform quadrant were considerably reduced （P<0.05） in the model group. In contrast to the model group, the EA group had a marked decrease in the escape latency, SP immunoactivity, and protein expression levels of Rab5, Rab7 and CTSD （P<0.05, P<0.01）, and a striking increase in the number of crossing the original platform and the swimming distance in the platform quadrant （P<0.05）. Results of transmission electron microscope showed an accumulation of endosome, lysosome, and endolysosomes in the hippocampal neurons in the model group, which was evidently milder in the EA group.

CONCLUSION

EA of GV20 and KI1 can improve the learning-memory ability of AD mice, which may be related to its function in reducing hippocampal Aβ deposition and down-regulating endosomal-lysosomal system activity.

[Effect of electroacupuncture on liver Akt/FoxO1 signaling pathway in rats with diabetic fatty]

OBJECTIVE

To observe the effect of electroacupuncture (EA) on liver protein kinase B (Akt)/forkhead box transcription factor 1 (FoxO1) signaling pathway in Zucker diabetic fatty (ZDF) rats, and to explore the possible mechanism of EA on improving liver insulin resistance of type 2 diabetes mellitus.

METHODS

Twelve male 2-month-old ZDF rats were fed with high-fat diet for 4 weeks to establish diabetes model. After modeling, the rats were randomly divided into a model group and an EA group, with 6 rats in each group. In addition, six male Zucker lean (ZL) rats were used as the blank group. The rats in the EA group were treated with EA at bilateral "Zusanli" (ST 36), "Sanyinjiao" (SP 6), "Weiwanxiashu" (EX-B 3), and "Pishu" (BL 20). The ipsilateral "Zusanli" (ST 36) and "Weiwanxiashu" (EX-B 3) were connected to EA device, continuous wave, frequency of 15 Hz, 20 min each time, once a day, six times a week, for a total of 4 weeks. The fasting blood glucose (FBG) in each group was compared before modeling, before intervention and after intervention; the serum levels of insulin (INS) and C-peptide were measured by radioimmunoassay method, and the insulin resistance index (HOMA-IR) was calculated; HE staining method was used to observe the liver tissue morphology; Western blot method was used to detect the protein expression of Akt, FoxO1 and phosphoenolpyruvate carboxykinase (PEPCK) in the liver.

RESULTS

Before intervention, compared with the blank group, FBG was increased in the model group and the EA group (P<0.01); after intervention, compared with the model group, FBG in the EA group was decreased (P<0.01). Compared with the blank group, the serum levels of INS and C-peptide, HOMA-IR, and the protein expression of hepatic FoxO1 and PEPCK were increased (P<0.01), while the protein expression of hepatic Akt was decreased (P<0.01) in the model group. Compared with the model group, the serum levels of INS and C-peptide, HOMA-IR, and the protein expression of hepatic FoxO1 and PEPCK were decreased (P<0.01), while the protein expression of hepatic Akt was increased (P<0.01) in the EA group. In the model group, the hepatocytes were structurally disordered and randomly arranged, with a large number of lipid vacuoles in the cytoplasm. In the EA group, the morphology of hepatocytes tended to be normal and lipid vacuoles were decreased.

CONCLUSION

EA could reduce FBG and HOMA-IR in ZDF rats, improve liver insulin resistance, which may be related to regulating Akt/FoxO1 signaling pathway.

[Perpendicular and transverse needling of "Sanyinjiao" (SP6) relieves abdominal pain by regulating arginine vasopressin and its receptor expression levels in uterus and hypothalamus in cold-stasis type dysmenorrhea rats]

OBJECTIVE

To observe the effect of perpendicular and subcutaneous transverse needling at "Sanyinjiao" (SP6) on visceral pain behavior, arginine vasopressin (AVP) content in the serum, uterine tissues, spinal cord and hypothalamus and expression of AVP receptors AVPR1A and AVPR1B in the uterine tissues, spinal cord and hypothalamus in cold-stasis (stasis due to pathogenic cold) type dysmenorrhea rats, so as to explore their mechanisms underlying pain relief.

METHODS

Forty female SD rats were randomly divided into blank control, model, perpendicular needling and transverse needling groups, with 10 rats in each group. The cold-stasis dysmenorrhea rat model was established by exposure in a freezer (-25 ℃) for 4 h, once daily for 5 days, and subcutaneous injection of estradiol benzoate (once daily for 10 days) and intra-abdominal injection of oxytocin injection (once). For rats of the two acupuncture groups, acupuncture needles were inserted into the bilateral SP6 perpendicularly or transversely to a depth of about 4-5 mm, and retained for 20 min. The abdominal pain behavior was assessed by recording the writhing latency and scaling the rats' writhing reactions after modeling. The contents of AVP in the serum, uterus, spinal cord and hypothalamus tissues were assayed using ELISA and the expression of AVPR1A and AVPR1B in the uterus, spinal cord and hypothalamus was measured by using Western blot and quantitative real time-PCR, respectively.

RESULTS

After mode-ling and compared with the blank control group, the writhing latency was significantly shortened (P<0.05), and the writhing score in the first 20 min was significantly increased (P<0.01) in the model group. After the intervention, the writhing latency was significantly prolonged (P<0.01), and the writhing scores in 20 min were significantly decreased (P<0.01) in the two needling groups. The AVP contents were obviously increased in the serum and uterine tissue (P<0.05, P<0.01) but decreased appa-rently in the spinal cord and hypothalamus tissues (P<0.01, P<0.05), and the expression levels of AVPR1A or AVPR1B protein and mRNA were markedly increased in the uterine tissues (P<0.01, P<0.05), and significantly decreased in the spinal cord and hypotha-lamus in the model group relevant to the control group (P<0.05, P<0.01). Following the intervention, The AVP content in the serum of the perpendicular needling group (P<0.05) and that in the uterus of the two needling groups were significantly decreased (P<0.01), as well as that in the hypothalamus was obviously increased in the two needling groups (P<0.05). The expression levels of AVPR1A protein and mRNA in the uterus were significantly down-regulated in the two needling groups (P<0.01, P<0.05) and AVPR1B protein in the hypothalamus of the perpendicular needling group was up-regulated (P<0.05). Moreover, no significant differences were found between the two needling groups in regulating the related indexes mentioned above (P>0.05).

CONCLUSION

Both perpendicular and subcutaneous transverse needling at SP6 have an immediate analgesic effect in cold-stasis type dysmenorrhea rats, which may be related to their effects in regulating AVP levels and its receptor expression in the uterine and hypothalamus.

[Effect of electroacupuncture of "Hegu" (LI4) and "Zusanli" (ST36) on intestinal sensitivity and motility in irritable bowel syndrome rats]

OBJECTIVE

To observe the effect of electroacupuncture (EA) of "Hegu"(LI4) and "Zusanli"(ST36)on changes of intestinal sensitivity and colonic motility and expression of colonic 5-hydroxytryptamine 3A receptor (5-HT_3AR) in irritable bowel syndrome (IBS) rats, so as to reveal its mechanism underlying improvement of IBS.

METHODS

A total of 40 neonatal Wistar rats were randomly and equally divided into normal control, model, LI4 and ST36 groups (n＝10). The IBS model was induced by mother-infant separation, acetic acid enema and colorectal distension (CRD). EA (2 Hz/100 Hz, a tolerable strength) was applied to bilateral LI4 and ST36 for 20 min, once every other day for 5 times. The Bristol stool form scale was used to assess the gastrointestinal function, and the latency and number of abdominal muscular contraction waves of abdominal withdrawal reflex (AWR) were used to evaluate the intestinal sensitivity and motility respectively. The immunoactivity of 5-HT_3AR of the colon tissue was detected by immunohistochemistry.

RESULTS

After modeling, the score of Bristol fecal form scale, number of muscular contraction waves and expression levels of colonic 5-HT_3AR in the myometrium and mucosal layers were significantly increased (P<0.01), and the latency of muscular initial contraction wave was obviously shortened in the model group relevant to the normal control group (P<0.01). After the intervention, the increased Bristol fecal form score, number of muscular contraction waves and expression levels of 5-HT_3AR in the myometrium and mucosal layers as well as the decreased latency of muscular contraction were reversed in both LI4 and ST36 groups (P<0.01, P<0.05). The effect of EA of ST36 was significantly superior to those of EA-LI4 in lowering Bristol fecal scale score and 5-HT_3AR expression in the muscular layer (P<0.01), but obviously inferior to those of EA-LI4 in increasing the latency of of muscular initial contraction wave and down-regulating muscular contraction waves and 5-HT_3AR expression in the mucosal layer (P<0.05, P<0.01).

CONCLUSION

Both EA-LI4 and EA-ST36 can significantly improve the symptoms of abdominal pain and diarrhea, but EA-LI4 is better in suppressing intestinal high sensitivity, and EA-ST36 is better in promoting intestinal motility, suggesting a specificity of effect of acupoints of different meridians.

[Effect of electroacupuncture at "Zusanli" (ST 36) and "Yanglingquan" (GB 34) on perinatal nicotine-exposure-induced lung function and morphology of neonatal rats]

OBJECTIVE

To compare the effects of electroacupuncture (EA) at "Zusanli" (ST 36) versus "Yanglingquan" (GB 34) in the pregnant rats on perinatal nicotine-exposure-induced lung function and morphology of newborn rats and explore the rule of acupoint effect in EA for the prevention from lung dysplasia in newborn rats.

METHODS

A total of 24 female SD rats were randomized into a normal saline group (S group), a nicotine group (N group), a nicotine-ST 36 group (N + ST 36 group) and a nicotine-GB 34 group (N+GB 34 group), 6 rats in each one. Starting at the 6th day of pregnancy, 0.9% sodium chloride solution was injected subcutaneously in the S group, 1 mg/kg; and in the rest 3 groups, nicotine of the same dose was injected through to the 21st postnatal day to establish the perinatal nicotine-exposure model. Simultaneously, during model preparation, EA was applied at "Zusanli" (ST 36) and "Yanglingquan" (GB 34) in the N+ST 36 group and the N+GB 34 group respectively, once a day, through to the 21st postnatal day. The lung function analytic system for small animal was adopted to observe the changes in lung function indicators in newborn rats, such as peak inspiratory flow (PIF), peak expiratory flow (PEF), expiratory resistance (RE), inspiratory resistance (RI) and dynamic compliance (Cdyn). HE staining was used to observe the morphological changes of lung, such as alveolar fusion and rupture.

RESULTS

Compared with the S group, PEF and Cdyn were lower and PIF, RI and RE higher in the N group (all P<0.01), additionally, alveoli were fused and ruptured, alveolar wall thickened, the numbers of alveoli reduced, the interspace of alveoli enlarged and the diameter increased (P<0.01). Compared with the N group, in the N+ST 36 group, PEF and Cdyn were increased, PIF, RI and RE reduced (P<0.05, P<0.01), the alveolar fusion and rupture relieved, the numbers of alveoli increased, alveolar wall thinner, the interpsace of alveoli became normal and the diameter was reduced significantly (P<0.01). In the N+GB 34 group, the changes of lung function and morphological indicators were not significant (P>0.05).

CONCLUSION

Electroacupuncture at "Zusanli" (ST 36) in the pregnant rats significantly improves the perinatal nicotine-exposure-induced lung function and morphology of newborn rats than electroacupuncture at "Yanglingquan" (GB 34).

[Comparison of effects of electroacupuncture at "Tianshu" (ST25) and "Dachangshu" (BL25) on intestinal sensitivity and expression of muscarinic M3R and 5-HT3AR in irritable bowel syndrome rats]

OBJECTIVE

To observe and compare the effect of electroacupuncture (EA) of "Tianshu" (ST25) and "Dachangshu" (BL25) on intestinal sensitivity and the expression of M₃ muscarinic acetylcholine receptor (M₃R) and 5-hydroxytryptamine 3A receptor (5-HT_3AR) in the colon tissue in irritable bowel syndrome (IBS) rats, so as to explore its mechanism underlying improvement of IBS.

METHODS

Forty newborn Wistar rats were randomly divided into blank control, model, ST25 and BL25 groups (n＝10 rats per group). The IBS model was established by joint application of maternal separation, acetic acid enema plus colorectal distension from day 8 to 21 after birth. At the age of 9 weeks, EA (2 Hz/100 Hz, 0.1－0.3 mA) was applied to ST25 and BL25 for 20 min, once every other day for 5 times. The modified method was used to record the abdominal withdrawal reflex (AWR), so as to evaluate the visceral sensitivity by referring to the modified Al-Chaer's and colleagues' methods. The threshold (initial wave), the number and peak-peak value of contraction waves (AWR) within 90 s were recorded. The immunoactivity of M₃R and 5-HT_3AR in the colon tissue was detected by immunohistochemistry.

RESULTS

After modeling, the latency was obviously shortened, the number and peak-peak values of contraction waves of intestine were significantly increased, and the immunoactivity of M₃R and 5-HT_3AR was notably up-regulated in the model group compared with the blank control group (P<0.01). After the EA intervention, the latency was obviously prolonged, the peak-peak value in both ST25 and BL25 groups, and the number of contraction waves in the ST25 group were significantly decreased (P<0.01), and the expression levels of M₃ and 5-HT_3A R were considerably down-regulated in both ST25 and BL25 groups relevant to the model group (P<0.01). The therapeutic effects were significantly better in the ST25 group than in the BL25 group in prolonging the latency and reducing the contraction wave number, and in down-regulating the expression of colonic M₃R and 5-HT_3AR (P<0.05, P<0.01).

CONCLUSION

EA at ST25 and BL25 can reduce the intestinal sensitivity in IBS rats, which is probably associated with its effects in down-regulating the expression of M₃R and 5-HT_3AR in the colon. The therapeutic effects of ST25 were obviously better than those of BL25 in suppressing intestinal sensitivity and expression of colonic M₃R and 5-HT_3AR.

[Electroacupuncture at "Zusanli" (ST36) and "Chize" (LU5) of mother rats exposed to nicotine during pregnancy and lactation has a protective effect on development of lung function and morphology in neonatal rats]

OBJECTIVE

To compare the different effect of electroacupuncture (EA) at "Zusanli" (ST36) and "Chize" (LU5) of mother rats exposed to Nicotine during pregnancy and lactation on lung function and morphological changes in offspring rats, so as to explore the most effective acupoint for improving the development of lung in neonatal rats.

METHODS

A total of 24 female pregnancy SD rats were randomly divided into 4 groups: normal control, model, EA-ST36 and EA-LU5 (n＝6 rats in each group). Rats of the normal group were treated by subcutaneous injection of normal saline, and those of the other 3 groups treated by subcutaneous injection of nicotine (1 mg•kg^－1•d^－1) beginning from the 6^th day to about the 21^st day of pregnancy (childbirth day) for nicotine exposure during pregnancy and lactation. The daily EA treatment (2 Hz /15 Hz，1 mA) was applied to bilateral ST36 and LU5 for 20 min, beginning from the 6^th day of pregnancy to the 21^st day (childbirth day). The lung function of the offspring rats including the peak inspiratory flow (PIF), peak expiratory flow (PEF), lung resistance (RL), exhalation resistance (RE)and lung dynamic compliance (Cdyn) was detected by using a lung function analysis system. Histopathological changes (severity of alveolarization) of the offspring rats' lung tissue were observed under microscope after H．E. stain.

RESULTS

Compared with the normal group, the PIF, RL and RE values were significantly increased (P<0.01), and PEF and Cdyn values significantly decreased in the model group (P<0.01). The alveolar diameter in the model group was evidently increased relevant to the normal group (P<0.01). Following the intervention, modeling induced increase of PIF, RL, RE and alveolar diameter and decrease of PEF and Cdyn values in the EA-ST36 group, and the increased PIF, RL and RE levels in the EA-LU5 group were obviously suppressed relevant to the model group (P<0.01, P<0.05). Additionally, modeling induced obvious congestion and edema of the alveolar wall, alveolar deformation, rupture and fusion, and reduction of the number of the pulmonary alveoli were evidently milder in both EA-ST36 and EA-LU5 groups. No significant differences were found between the EA-ST36 and EA-LU5 groups in the abovementioned 5 indexes of pulmonary function and alveolar diameter (P>0.05)．.

CONCLUSION

EA of ST36 and LU5 of mother rats experiencing nicotine exposure during pregnancy and lactation can improve the lung function and morphological changes in neonatal rats, and the effect of ST36 is relatively better.

[Effect of Electroacupuncture at "Neiguan" (PC 6) and "Tianshu" (ST 25) for Colonic Motility and D 2 Receptor in Irritable Bowel Syndrome Rats]

OBJECTIVE

To observe and compare the effects of electroacupuncture (EA) at "Tianshu" (ST 25) and "Neiguan" (PC 6) for colonic motility and the expression of colon dopamine D 2 in irritable bowel syndrome (IBS) rats, and to explore the specificity of different meridians and different acupoints.

METHODS

Forty Wistar newborn rats were randomly divided into blank, model, Tianshu and Neiguan groups. Separation of mother and child and acetic acid coloclyster combined with colorectal distension were used to establish IBS model in the model, Tianshu and Neiguan groups. At the age of 9 weeks, EA at bilateral ST 25 and PC 6 were applied in the corresponding groups 5 times, once every other day. After the intervention, the Bristol fecal score, the latent period of abdominal retraction reflex and the number of contraction waves were recorded. The expression of dopamine D 2 receptor was detected by immunohistochemistry.

RESULTS

Compared with the blank group, the Bristol fecal score of the model group was higher (P<0.01), the 1^st contraction wave latent period was shorter (P<0.01), the number of contraction waves in 90 s increased (P<0.01), the immunoreactive expression of D 2 receptor in colon decreased (P<0.01). Compared with the model group, the Bristol fecal scores of the Tianshu and Neiguan groups decreased (P<0.01), the 1^st contraction wave latent periods were longer (P<0.01), the numbers of contraction waves in 90 s decreased (P<0.01), the positive expressions of D 2 receptor in colon increased (P<0.01, P<0.05). Compared with the Tianshu group, the immunoreactive expression of D 2 receptor in the Neiguan group decreased (P<0.01).

CONCLUSION

EA at ST 25 and PC 6 can improve the symptoms of colonic motility in IBS rats. The effect of EA at ST 25 is better, which indicates that different meridians and different acupoints play specific effects.

[Effect of Electroacupuncture at "Neiguan" (PC 6) on Skin Microcirculation Blood Perfusion Volume of Heart-related Acupoints and Heart-irrelevant Acupoints in Myocardial Ischemia Rats]

OBJECTIVE

To observe the effect of low-frequency or high-frequency electroacupuncture (EA) stimulation of "Neiguan" (PC 6) on changes of skin blood perfusion volume of heart-related and heart-irrelevant acupoints in rats with normal or ischemic myocardium.

METHODS

Wistar rats were randomly divided into the control, sham-operation, model, low-frequency EA and high-frequency EA groups (n=8 in each group). The myocardial ischemic (MI) model was established by occlusion of the anterior descending branch of the left coronary artery. 2 Hz and 100 Hz EA was respectively applied to left PC 6 for 20 min, once daily, a total of three times. Electrocardiogram (ECG) was recorded after the last treatment. Serum cardiac troponin T (cTnT) contents were assayed by ELISA. The skin blood perfusion volumes of bilateral PC 6, "Zusanli" (ST 36) and "Yanglingquan" (GB 34) were observed by laser speckle contrast imaging.

RESULTS

In comparison with the control and sham-operation groups, the differences of "J point" and contents of serum cTnT were significantly increased in the model group (P<0.01). After EA, the differences of "J point" and contents of serum cTnT were significantly decreased in both low-frequency and high-frequency EA groups (P<0.01, P<0.05). Compared with the control group, the skin blood perfusion volumes of bilateral PC 6 and ST 36 decreased obviously in rats of the model group (P<0.01). After EA, the skin blood perfusion volumes were markedly up-regulated in the areas of PC 6 and ST 36 (P<0.01). There were no significant changes in that of GB 34 among the 5 groups (P<0.05).

CONCLUSIONS

Skin blood perfusion volumes around PC 6 and ST 36 can specifically reflect the change of the myocardial state.

[Effect of Electroacupuncture at "Yintang" (GV 29) and "Tianshu" (ST 25) on the Ethology and the Expression of TRPV 1 Receptor in Colon of Irritable Bowel Syndrome Rats]

OBJECTIVE

To observe the ethology and expression of transient receptor potential vanilloid-1(TRPV 1) in colon of irritable bowel syndrome (IBS) rats treated by electroacupuncture (EA) at "Yintang" (GV 29) and "Tianshu" (ST 25), so as to explore the different effectiveness of different acupoints and its related mechanism underlying improvement of the symptoms of somatopsychic illness.

METHODS

Thirty-two neonatal Wistar rats were randomly divided into blank control group, model group, Yintang (GV 29) group, and Tianshu (ST 25) group (n=8 in each group). IBS model was established by neonatal maternal separation and acetic acid enema combined with colon and rectum expansion stimulation. Rats of the GV 29 and ST 25 groups were given EA treatment at age of 9 weeks old, 20 minutes, once every other day for 5 times. Latency of the 1^st time contraction wave and numbers of contractive wave in 90 s were recorded to evaluate abdominal visceral sensitivity by abdominal withdrawal reflex. Horizontal and vertical movements were observed to assess the emotional and psychological behavior of rats by open field test. TRPV 1 expression in colon was detected by immunohistochemistry method.

RESULTS

Compared with the black control group, latency of the 1^st time contractive wave was significantly shortened and the wave numbers in 90 s were increased significantly in the model group (P<0.01), while the numbers of vertical and horizontal movements were also significantly reduced (P<0.01), accompanied with increased TRPV 1 expression in the colon (P<0.05). Compared with the model group, After EA intervention, the levels of the above-mentioned 5 indexes were significantly reversed in the GV 29 and ST 25 groups (P<0.01,P<0.05), except the number of horizontal movement in the ST 25 group (P>0.05). The expression level of TRPV 1 was significantly lower in the ST 25 group than in the GV 29 group (P<0.01).

CONCLUSIONS

EA at GV 29 and ST 25 can alleviate the abdominal pain and improve the mental and emotional disorders in IBS rats. GV 29 has a better effect on relieving the depressive-like psychoemotional behavior of IBS rats, while ST 25 is more effective in treating abdominal pain. There is significantly different influence on TRPV 1 expression in colon between these two treatment groups, which may contribute to their different effect in pain relieving.

Acupuncture De-qi: From Characterization to Underlying Mechanism

De-qi refers to the participant's subjective sensations and objective body responses as well as the acupuncturist's perceptions while the acupuncturist needles certain acupoints in the participant's body. In recent years, De-qi is getting increasing attention of the researchers and many efforts have been made to understand its mechanism. By the broad literature survey, this paper explores the subjective De-qi sensation of the patients, its influencing factors, and the resulting physiological responses. The purpose of this paper is expected to find out a possible mechanism of De-qi and to provide certain scientific evidence for acupuncture fundamental research and clinical practice.

First Report of Root-Knot Nematode Meloidogyne arenaria on Atractylodis macrocephalae in China

Atractylodis macrocephalae is an important Chinese herbal medicine plant and its rhizome is of high medicinal value. In recent years, a severe decline in yield has been observed in Bozhou City (China's largest A. macrocephalae producing area), Anhui Province, China. A survey for plant-parasitic nematodes was conducted in this area from June to September 2011. Stunted plants displayed chlorotic or necrotic lower leaves near the ground part by the growth reduction; examination of the roots of stunted plants revealed the presence of galls typical of infestation by root knot nematode. Root nodules were found on the tap and lateral roots caused the fleshy tap root deformity. The incidence of diseased plants was estimated to be 45%, and yield loss was quantified as 43.5%. Nematodes were extracted from the root samples as previously described (4) and identified by morphology, enzyme analysis, and molecular characterization. Morphology of the female perineal patterns and measurements of the second-stage juveniles (J2s) matched those of the original description of Meloidogyne arenaria. Enzyme analysis of the esterase (Est) phenotype was also typical of the AII phenotype in M. arenaria (2). DNA was extracted according to a modified protocol (1), and the rDNA-internal transcribed spacer (ITS1_5.8S_ITS2) region was amplified with universal primers V5367 (5'-TTGATTACGTCCCTGCCCTTT-3') and 26S (5'-TTTCACTCGCCGTTACTAAGG-3'). PCR yielded a fragment of 764 bp and the purified product was sequenced by Sanger's dideoxy chain termination method (ABI3730). Sequences were identical to that of M. arenaria in GenBank (Accession No. AF387092) (3). Amplification of the D2/D3 fragments of the 28S RNA with universal primers D2A (5'-ACAAGTACCGTGAGGGAAAGTTG-3') and D3B (5'-TCGGAAGGAACCAGCTACTA-3') yielded a PCR fragment of 758 bp. These sequences were also identical to that of M. arenaria in GenBank (Accession No. AF435803). For further confirmation, amplification of the IGS region with universal primers 5S (5'-TTAACTTGCCAGATCGGACG-3') and 18S (5'-TCTAATGAGGGAACCAGCTACTA-3') yielded a PCR fragment of 713 bp. These sequences were 99.64% homologous to that of M. arenaria (GenBank Accession No. MAU42342). To our knowledge, this is the first report of M. arenaria species on A. macrocephalae in China. The fleshy tap root of A. macrocephalae is the main edible part of the plant, and the damage caused by root knot nematode will potentially reduce the yield and quality of this herb. References: (1) J. L. Cenis et al. Phytopathology 83:76, 1993. (2) P. R. Esbenshade and A. C. Triantaphyllou. J. Nematol. 17:6, 1985. (3) T. C. Vrain et al. Appl Nematol. 15:563, 1992. (4) L. F. Wang et al. Forest Res. 14:484, 2001.

[Effects of electroacupuncture on pain reactions, expression of spinal kappa-opioid receptor and contents of enkephalin and beta-endorphin in periaqueductal gray of midbrain in dysmenorrhea model rats]

OBJECTIVE

To observe effects of electroacupuncture (EA) on the expression of kappa-opioid receptor in the dorsal horn of the spinal cord and contents of enkephalin(ENK) and beta-endorphin (beta-EP) in the periaqueductal gray (PAG) of midbrain in dysmenorrheal rats, so as to reveal its underlying mechanism in relieving dysmenorrhea.

METHODS

A total of 80 female SD rats were randomized into saline control (control), model, Sanyinjiao (SP 6), Xuanzhong (GB 39), non-acupoint groups (16 rats/group). Dysmenorrhea model was established by subcutaneous injection of estradiol benzoate (0.5 mg/rat on the 1st day and 10th day, 0.2 mg/rat from the 2nd day to the 9th day). One hour after the last injection, oxytocin (2 U/rat) was given intraperitoneally, for rats of the control group, the same dose of saline was given (i. p.). On the 10th day, EA (2 Hz/100 Hz, 0.1-0.3 mA) was applied to "Sanyinjiao" (SP 6), "Xuanzhong" (GB 39) and non-acupoint (the mid-point between the Stomach Meridian and Gallbladder Meridian, and in parallel with GB 39) for 20 min, respectively. Latency and number of writhing response, and writhing score (according to Schmauss's and Yaksh's method) were recorded. The expression of kappa-opioid receptor (kappa-OR) in T13, L1 , L2, L6 and S1 segments of spinal cord was determined by immunohistochemistry, and the contents of ENK and beta-EP in the midbrain PAG were assayed by ELISA.

RESULTS

(1) Compared with the saline control group, the writhing latency of the model group was significantly shortened (P < 0.01), while the writhing times and writhing score of the model group were increased significantly (P < 0.01). Compared with the model group, the writhing latency of SP 6 group was significantly prolonged (P < 0.05), while the writhing scores and writhing times of the SP 6, GB 39 and the non-acupoint groups decreased significantly (P < 0.01). (2) In comparison with the control group, kappa-OR expression in the dorsal horn of L2 segment of spinal cord was upregulated significantly in the model group (P < 0.05). Compared to the model group, kappa-OR expression levels in the dorsal horns (DHs) of spinal T13, L1, L2, L6 and S1 segments in the SP 6 group were upregulated significantly (P < 0.01). ENK and beta-EP contents of PAG in the SP 6 and GB 39 groups were increased considerably (P < 0.01, P < 0.05). The effects of SP 6 were significantly superior to those of GB 39 in upregulating kappa-OR expression of spinal L1, L2 and L6 DHs and in upregulating beta-EP content of PAG; and superior to non-acupoint in upregulating kappa-OR expression of spinal T13, L1, L2, L6 and S1 DHs and in increasing both ENK and beta-EP contents of PAG (P < 0.01, PF < 0.05). No significant differences were found between the non-acupoint group and the model group in writhing latency, kappa-OR expression levels of spinal T13, L1, L2 and S1 DHs, and in ENK and beta-EP contents of PAG (P > 0.05).

CONCLUSION

EA of SP 6 can significantly alleviate pain reactions in dysmenorrhea rats, which is closely associated with its functions in upregulating spinal kappa-OR expression and ENK and beta-EP contents in PAG. EA of SP 6, GB 39 and non-acupoint has some different degrees of efficacies in relieving dysmenorrhea and in upregulating spinal K-OR expression.

[Effects of instant electroacupuncture at the different acupoints on IP3 in the uterus tissue of dysmenorrhea model rats]

OBJECTIVE

To compare the effects of instant electroacupuncture (EA) at the different acupoints on IP3 in the uterus tissue of dysmenorrhea model rats so as to investigate the specificity of acupoints.

METHODS

Fifty female SD rats were randomly divided into a saline group, a model group, a Sanyinjiao (SF 6) group, a Xuehai (SP 10) group and a Hegu (LI 4) group, 10 rats in each group. The rats were given subcutaneous injection of Estradiol Beozoate injection for 10 consecutive days except those in the saline group, and intraperitoneal injection of 2U Oxytocin at 1 h after the last administration to create the dysmenorrhea rats model, and the saline group was given the same dose of saline every day. On the 10th day the rats in each EA group were given EA 20 min, and the rats in the saline group and model group were bound 20 min, and the writhing response was observed at the same time. The uterine IP3 contents were detected with enzyme-linked immunosorbent assay method.

RESULTS

(1) Compared with (0.311+/- 0.253) in the saline group, the writhing scores per minute of (5.867 +/- 3.442) in the model group and (2.311 +/- 0.957) in the Xuehai (SP 10) group were both increased significantly (P < 0.01, P < 0.05), and (1.833 +/- 1.355) in the Sanyinjiao (SP 6) group and (0.743 +/- 0.306) in the Hegu (LI 4) group showed no significant differences (P > 0.05). Compared with that in the model group, the writhing scores per minute decreased significantly (all P < 0.01) in all the EA groups, with no significant differences among all the EA groups (all P > 0.05). (2) Compared with (2.698 +/- 1.491) ng/mg in the saline group, IP3 contents of the uterus of (0.813 +/- 0.899) ng/mg in the model group, (1.740 +/- 0.375) ng/mg in the Sanyinjiao (SP 6) group and (0.692 +/- 0.212) ng/mg in the Hegu (LI 4) group were all lower significantly (P < 0.05, P < 0.01), and (0.743+/- 0.306) ng/mg in the Xuehai (SP 10) group showed no significant differences (P > 0.05). Compared with that in the model group, IP3 content of the uterus in the Hegu (LI 4) group showed no significant difference (P > 0.05), and those in the Sanyinjiao (SP 6) group and in the Xuehai (SP 10) group increased significantly (both P < 0 05), which were significantly higher than that in the Hegu (II 4) group (P < 0.05, P < 0.01).

CONCLUSION

There are no significant differences among the instant EA groups in improving the dysmenorrhea symptoms, but there is obvious specificity of acupoint effects in the regulation of IP3. Electroacupuncture at "Sanyinjiao (SP 6) " Xuehai (SP 10)" has more marked effect in dysmenorrhea model rats.

[Effects of electroacupuncture of "Sanyinjiao" (SP 6) on contents of MDA and beta-EP, and expression of HSP 70 in the uterus in rats with dysmenorrhea]

OBJECTIVE

To investigate the effect of electroacupuncture (EA) of "Sanyinjiao" (SP 6) on the uterus in dysmenorrhea rats so as to study its underlying analgesic mechanism.

METHODS

A total of 48 SD rats during diestrus were randomized into normal saline (control) group, model group and acupuncture group according to a random number table, with 16 rats in each group. Dysmenorrhea model was established by subcutaneous injection of Estradiol benzoate (0.5 mg/d on the 1st and 10th day, and 0.2 mg/d from day 2 to day 9, once daily for 10 days) and oxytocin (2 U/rat, once on day 10). Malondialdehyde (MDA) and beta-endorphin (beta-EP) contents in the uterus were detected by radioimmunoassay, and the heat shock protein 70 (HSP 70) immunoactivity of the uterus was detected by immunohistochemistry.

RESULTS

In comparison with the control group, MDA content in the uterus was increased significantly in the model group (P < 0.01), while the beta-EP level and the immunoactivity of HSP 70 immune-reaction (IR) positive products in the uterus decrease significantly (P < 0.01) and moderately, respectively in the model group. In comparison with the model group, uterine MDA content in the EA group was decreased significantly (P < 0.01), while uterine beta-EP level increased considerably (P < 0.01) and HSP 70 expression was upregulated to a certain degree.

CONCLUSION

EA of "Sanyinjiao" (SP 6) can reduce MDA content and upregulate beta-EP level of the uterus in rats with dysmenorrhea, which may contribute to its analgesic effect in relieving dysmenorrhea by clearing away oxygen free radicals and raising analgesic substance in the uterus.

[Comparative study on the analgesic effect of electroacupuncture at "Sanyinjiao" (SP 6), "Hegu" (LI 4) and "Xuehai" (SP 10) in dysmenorrhea rats]

OBJECTIVE

To observe and compare the analgesic effect of electroacupuncture (EA) at "Sanyinjiso" (SP 6), "Hegu" (LI 4) and "Xuehai" (SP 10) in dysmenorrhea rats so as to investigate the functional specificity of acupoint.

METHODS

One hundred SD female rats aged three-month-old in the diestrus examined by the vaginal smear screening were randomly divided into a saline group, a model group, a Sanyinjiao (SF 6) group, a Hegu (LI 4) group and a Xuehai (SF 10) group, 20 rats in each group. The rats in the last four groups were given Estradiol Benzoate combined with Oxytocin to prepare the models of dysmenorrhea and in the saline group were given the same dose of saline. Last three groups were treated with electroacupuncture (EA) at Sanyinjiao" (SF 6), "Hegu" (LI 4) and 'Xuehai" (SF 10) respectively. The writhing behaviors of the rats in each group were observed within 20 min performing electroacupuncture from the start of the pain and the waveforms of uterine contraction were recorded.

RESULTS

In terms of the writhing behaviors, the writhing latency in the Hegu (LI 4) group was extended significantly (P < 0.05, P < 0.01) and the writhing numbers in the Hegu (LI 4) group were decreased significantly (both P < 0.05) as compared with those in the Sanyinjiao (SF 6) group and in the Xuehai (SF 10) group. In terms of the waveforms of uterine contraction, compared with that in the model group, the amplitude and the activity of uterine contraction in both Sanyinjiao (SF 6) group and Hegu (LI 4) group were decreased significantly (all P < 0.05), and with no significant difference between the Xuehai (SF 10) and the model group (P > 0.05).

CONCLUSION

For comprehensive assessment of the analgesic effect of electroacupuncture at different acupoints by using the writhing behaviors and the waveforms of uterine contraction, "Hegu" (LI 4) is the best, "Sanyinjiao" (SP 6) is the next and "Xuehai" (SP 10) is the third. showing a relatively functional specificity of the acupoint.

Molecular and immunological approaches to mammalian fertilization

By means of hybridoma technology, we obtained six hydriboma cell lines producing monoclonal antibody (mAb) to porcine zona pellucid (ZP), two of which recognizes the steric structure of common antigens between porcine ZP and humans. Furthermore, we have analyzed all or partial structures of N- and O-linked sugar chains of ZP glycprotein from porcine or murine oocytes. Then, we have clarified that beta-galactose and Le(X) residues on ZP played the binding roles to sperm cells in porcine and murine fertilization. We have also succeeded Sp38 cDNA cloning from cDNA library of porcine testis. We found that Sp38 protein bind to porcine ZP2 and expressed in murine and human sperm cells. Corresponding to the presence of major histocompatibility complex (MHC) class II on murine sperm, CD4 on the murine egg plasma membrane was clearly shown by indirect IIF and immunoprecipitation test. Furthermore, the transcriptional expression of CD4/p56(lck) in eggs was confirmed by RT-PCR method. In addition, the p56(lck) associated with CD4 underneath the plasma membrane of eggs was autophosphorylated after cross-linking of CD4 with anti CD4 mAb. The binding between eggs or Sf9-CD4 cells labeled with anti-CD4 mAb and sperm cells labeled with anti-monomorphic region of class II mAb was completely blocked. Considering these findings together with the fact that an interspecies' heterogeneity is present in CD4 amino acid sequence at the interactive site with class II, we elucidated that one of species' specific intercellular adhesions between two gametes at the fusion step in fertilization is definitely mediated by class II located on the posterior region of sperm head and CD4/p56(lck) complex on the plasma membrane of egg.

Expression of Fas-Fas ligand in murine testis

PROBLEM

During spermatogenesis, it has been suggested that the number of germ cells to be matured is regulated and restricted through the apoptotic mechanism. In the present study, we investigated the expression and apoptotic role of Fas and Fas ligand (L) in the murine testis.

METHOD OF STUDY

The expression of Fas-FasL in the murine testis was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR)-Southern blot hybridization, in situ hybridization, and Western blot methods. The terminal deoxynucleotide transferase mediated dUTP-nick end label (TUNEL) and DNA fragmentation methods were applied to detect the generation of apoptosis in germ cells.

RESULTS

By means of RT-PCR-Southern blot hybridization, we demonstrated the positive expression of Fas in testicular germ cells, and of FasL in testicular cells. supporting the findings with in situ hybridization that Fas was localized in germ cells, whereas FasL was localized in Sertoli cells of murine testis. A specific band at 45 kDa was obtained in the lysates from testis and germ cells with Western blot analysis. Then, the co-incubation of germ cells with Spodoptera frugiperda (Sf9)-FasL cells in vitro resulted in the induction of apoptosis in germ cells detected by the TUNEL method. Furthermore, DNA fragmented ladders were also demonstrated in germ cells co-incubated with Sf9-FasL cells.

CONCLUSION

Fas-FasL system seemed to play an apoptotic role in spermatogenesis by the molecular interaction between FasL on Sertoli cells and Fas on germ cells.

Aberrant expression and dysfunction of Fas antigen in MRL/MpJ-lpr/lpr murine ovary

In lpr mice the insertion of an early transposable element (ETn) into intron 2 of the Fas gene, which mediates apoptosis, causes the development of massive lymphadenopathy, splenomegaly and autoimmune disease. In the present study we investigated the influence of this mutation on ovarian development of lpr mice. By means of in situ hybridisation, the expression of Fas mRNA was detected at the same levels in the ovarian cells of MRL/MpJ-lpr/lpr (MRL/lpr) mice as in those of MRL/MpJ-(+)/+ (MRL/+) mice. However, indirect immunofluorescence (IIF) staining with anti-Fas monoclonal antibody (mAb) on the membrane of follicle and egg of MRL/lpr mice was significantly weaker than that of MRL/+ mice. Furthermore, the expression level of Fas protein at the 45 kDa band from ovarian cell lysates of MRL/lpr mice was much lower than that of MRL/+ mice. The co-incubation of Spodoptera frugiperda (Sf9)-Fas lig- and (L) cells with eggs of MRL/+ mice resulted in apoptosis of eggs, as detected by the terminal deoxynucleotide transferase mediated dUPT-nick end labelled (TUNEL) method. In contrast the co-incubation of Sf9-FasL cells with eggs of MRL/lpr mice did not generate apoptosis in eggs. Following intraperitoneal administration of anti-Fas mAb into both types of mice, most oocytes, a proportion of granulosa cells in the ovary and hepatocytes in liver of MRL/+ mice were positively stained by the TUNEL method, corresponding to the appearance of DNA fragmented ladders by DNA fragmentation assay, while negative signals were obtained in those cells of MRL/lpr mice. As the mice aged, the ovarian size of MRL/lpr mice was found to be much larger than that of MRL/+ mice due to the increased number of ovarian follicles. Therefore, the ovarian adenopathy in MRL/lpr mice was strongly suggested to be caused by the dysfunction of Fas antigen in the ovary.

Isolation and identification of apoptosis inducing nucleosides from CD57(+)HLA-DRbright natural suppressor cell line

The CD57(+)HLA-DRbright natural suppressor (57.DR-NS) cell line derived from human decidual tissue generated the apoptosis in K562/Molt4 target cells mediated by soluble factors released into the culture supernatant. The factors in the culture fluid of the 57. DR-NS cell line were isolated by the physicochemical procedures as follows, first by a preparative octadecyl sorbent column, further by thin-layer-chromatography (TLC), finally by reverse-phase high-performance liquid chromatography (HPLC). The six major components (P1-P6) obtained by HPLC demonstrated the generation of apoptotic cell death of target cells. The physicochemical characters of six active components were strongly suggested to be nucleosides and their modified forms in nature. Then, the physicochemical structures of the six active components were finally determined by fast atom bombardment-mass spectrometry (FAB-MS) and nuclear magnetic resonance (1H NMR) spectrometry as follows: P1, 2'-deoxyuridine; P2, ribothymidine; P3, 2'-O-methyluridine; P4, thymidine; P5, 2'-O-methylinosine; P6, 2'-O-methylguanosine. Thus, we collectively named them "apoptosis inducing nucleosides (AINs)." Then, we demonstrated that the induction of apoptosis in target cells by the 57.DR-NS cell line was mediated by a series of AINs.

Receptive field properties of visual neurons in the avian nucleus lentiformis mesencephali

The receptive field (RF) properties of visual neurons extracellularly recorded from the nucleus lentiformis mesencephali (nLM) in pigeons (Columba livia) were quantitatively analyzed using a workstation computer. These cells were actively spontaneous, and direction-and velocity-selective. Using spatial gratings as visual stimuli, these cells could be divided into three groups: uni- (74%), bi- (17%), and omnidirectional (9%) cells in terms of their directionality. On the basis of their velocity selectivity, they could be named slow cells (84%), preferring low velocity (0.1-11 degrees/s), and fast cells (14%), preferring rapid motion (34-67 degrees/s), with one cell (2%) responding maximally to an intermediate velocity of 18 degrees/ s. These two properties were correlated in the way that all unidirectionals were slow cells, omnidirectionals were fast cells, and bidirectionals were either slow or fast cells including the intermediate cell. Using small targets as visual stimuli, it was found that the majority of cells examined had RFs that each consisted of an excitatory RF (ERF) and an inhibitory RF (IRF) that overlapped. The unidirectionals were mainly of this type of RF structure, whereas the omnidirectionals apparently had ERFs alone. The direction preference of ERF was opposite to that of IRF for unidirectional cells tested, whereas they were perpendicular to each other for one bidirectional cell. The overall responses of these cells resulted from interaction between excitation and inhibition induced by directionally different motion. Under certain conditions, visual responses of a particular cells to a small target moving through its ERF were equal in responsive strength to those to whole-field gratings swept over the screen. It was suggested that optokinetic nystagmus produced by wholefield gratings results from population activity of large group(s) of neurons in some optokinetic nuclei, at least one of which is nLM.

Expression of Fas-Fas ligand system associated with atresia in murine ovary

We detected that Fas receptor (Fas) was expressed at transcriptional levels in oocytes/eggs and some granulosa cells of murine ovary, whereas, Fas ligand (FasL) was found to be strongly expressed in granulosa cells by means of in situ hybridisation. These results were supported by an indirect immunofluorescence (IIF) test with anti-Fas monoclonal antibody (mAb)/FasL Ab. The lysates from granulosa cells were precipitated by anti-FasL Ab, exhibiting a specific band at 40 kDa. When zona pellucida (ZP)-free eggs were incubated with granulosa cells in vitro, apoptosis (DNA fragmentation) was induced in the eggs, as detected by the terminal deoxynucleotide transferase mediated dUTP-nick end labelling (TUNEL) method. To examine whether FasL-bearing cells can induce apoptosis in eggs expressing Fas through molecular interaction between FasL and Fas, we employed a baculovirus expression system to generate FasL on the surface of Spodoptera frugiperda (Sf9) cells. The co-incubation of eggs with Autographa californica nuclear polyhedrosis virus (AcNPV) and FasL transfected Sf9 (Sf9-FasL) cells in vitro was performed and resulted in the induction of apoptosis in eggs as detected by the TUNEL method. Apoptosis was absent in eggs co-incubated with AcNPV-1393 transfected Sf9 (Sf9-1393) cells. Thus, ovarian atresia was suggested to be induced by molecular interaction between FasL on granulosa cells and Fas on oocytes/eggs during oogenesis.

Expression of Fas ligand in murine ovary

Corresponding to the expression of Fas in the ovarian oocytes as previously reported (Guo et al., Biochem Biophys Res Commun 1994; 203:1438-1446; Mori et al., JSIR 1995; 9:49-50), the expression of Fas ligand (FasL) in the ovarian follicle was found to be restricted in the area of granulosa cells by the indirect immunofluorescence (IIF) test. Reverse transcriptase/polymerase chain reaction (RT/PCR) technique coupled with Southern blot hybridization analysis showed that the highest level of FasL mRNA was demonstrated in murine ovaries and granulosa cells 1 day after the administration of pregnant mare's serum gonadotropin (PMSG), while the level of FasL mRNA became very weak on the day 5, respectively. The observed gradual decrease in FasL mRNA could not be attributed to a generalized degradation of cellular RNA during atresia, as evidenced by the presence of constitutive expression of elongation factor 1 alpha (EF-1 alpha) mRNA in murine ovaries and granulosa cells treated with PMSG. Furthermore, in situ hybridization analysis with a FasL-specific probe confirmed that FasL was specifically localized in the granulosa cells of most follicles and its expression was regulated by PMSG administration. FasL localized in granulosa cells might possibly play an important role in the formation of the ovarian atretic follicles, most likely depending on PMSG administration.

Expression of Fas-Fas ligand system associated with atresia through apoptosis in murine ovary

We examined the contribution of Fas and its ligand (FasL) in the process of follicular atresia using murine intraovarian follicles and pregnant mare's serum gonadotropin (PMSG)-hyperovulated eggs. Reverse transcriptase/polymerase chain reaction-Southern blot hybridization demonstrated positive expression of Fas in both intraovarian oocytes and hyperovulated eggs. In contrast, expression of FasL was only detected in granulosa cells. These findings were histologically confirmed by in situ hybridization using Fas- and FasL-specific probes. A time-course study showed that Fas mRNA was positive in atretic follicles through day 0 and day 2 of PMSG stimulation and negative thereafter. Levels of FasL mRNA were the highest on day 1 and tapered off toward day 5 of PMSG stimulation. Levels of elongation factor 1 alpha mRNA, a constitutive element, were constantly maintained throughout the experimental period. Coculture of ovulated eggs, intact and zona-free, and granulosa cells demonstrated positive TUNEL staining only in zona-free eggs. These findings indicate that follicular atresia is caused by apoptosis, and the apoptosis associated with internucleosomal DNA fragmentation is directly regulated by the Fas/FasL system.

Molecular structure and function of CD4 on murine egg plasma membrane

In the present study, the expression of the CD4 molecule on murine egg plasma membrane was confirmed by the indirect immunofluorescence (IIF) method. The full-length CD4 cDNA from murine eggs was synthesised by the reverse transcriptase-polymerase chain reaction (RT-PCR) method and its authenticity verified by Southern blot hybridisation using an end-labelled internal oligonucleotide. The results of DNA sequencing showed that the nucleotide sequence of the cDNA of CD4 from murine egg mRNA was identical to that of immune T cells. To demonstrate the direct interaction of CD4 from murine egg with murine sperm cells bearing MHC (major histocompatibility complex) class II molecule, we employed a baculovirus expression system to generate CD4 on the surface of Spodoptera frugiperda (Sf9) cells. Expression of CD4 on Sf9 cells infected with Autographa californica nuclear polyhedrosis virus (AcNPV)-CD4 was demonstrated by IIF and immunoblotting. The CD4-expressing Sf9 cells adhered to MHC class II-bearing sperm cells since the adhesion was specifically blocked by anti-CD4 monoclonal antibody (mAb) or anti-monomorphic region of MHC class II mAb. Taking our previous and present experimental results together, they strongly suggest that intercellular membrane adhesion between two gametes at the fusion step in fertilisation is mediated by the MHC class II molecule located on the posterior region of the sperm head and the CD4 molecule on egg plasma membrane.

Identification of Fas antigen associated with apoptotic cell death in murine ovary

The majority of ovarian follicles including oocytes undergo atresia through a mechanism involving apoptotic cell death. The mechanisms underlying atresia remain to be clarified. In the present study, we detected the expression of the Fas antigen (Fas), which is a cell-surface protein to modulate apoptosis, in murine ovarian oocytes and hyperovulated eggs as well as in several control tissues. Substantial decline in Fas mRNA was found in atretic follicles which were injected with pregnant mare's serum gonadotropin (PMSG) on day 3. The observed decreases in mRNA of Fas could not be attributed to a generalized degradation of cellular RNA during atresia, as evidenced by the presence of intact 18S and 28S ribosomal RNA as well as constitutive expression of EF-1 alpha mRNA in atretic follicles. The data obtained indicate that apoptotic cell death of oocytes seemed to be associated with internucleosomal DNA fragmentation regulated by Fas molecule expressed in atretic ovarian follicles.