Lycium barbarum polysaccharide alleviates DSS-induced chronic ulcerative colitis by restoring intestinal barrier function and modulating gut microbiota

PURPOSE

This study examined the protective effects and mechanism of Lycium barbarum polysaccharides (LBP) in the context of intestinal barrier function and intestinal microbiota in mice with dextran sulfate sodium (DSS)-induced chronic ulcerative colitis (UC).

METHODS

C57BL/6J male mice were assigned to a standard normal diet without DSS (control group), a normal diet with DSS (DSS group, 2% DSS given discontinuously for 3 weeks) or a normal diet supplemented with LBP (1% dry feed weight, LBP group, 2% DSS given discontinuously for 3 weeks) for a total of 8 weeks, at which point colonic tissues and caecal contents were collected.

RESULTS

LBP exerted a significant effect against colitis by increasing body weight, colon length, DAI and histopathological scores. LBP inhibited proinflammatory cytokines (IL-1β, IL-6, iNOS and TNF-α) expression, improved anti-inflammatory cytokine (IL-10) expression, promoted the expression of tight junction proteins (Occludin and ZO-1) via nuclear factor erythroid 2-related factor 2 (Nrf2) activation and decreased Claudin-2 expression to maintain the intestinal mucosal barrier. In addition, the abundances of some probiotics (Ruminococcaceae, Lactobacillus, Butyricicoccus, and Akkermansia) were decreased with DSS treatment but increased obviously with LBP treatment. And LBP reduced the abundance of conditional pathogens associated with UC (Mucispirillum and Sutterella). Furthermore, LBP improved the production of short-chain fatty acids (SCFAs), including acetic acid, propionic acid, butyric acid and isobutyric acid.

CONCLUSION

LBP can alleviate DSS-induced UC by regulating inflammatory cytokines and tight junction proteins. Moreover, LBP promotes probiotics, suppresses conditional pathogens and increases SCFAs production, showing a strong prebiotic effect.

[Development and validation of a prognostic prediction model for patients with stage Ⅰ to Ⅲ colon cancer incorporating high-risk pathological features]

Objective: To examine a predictive model that incorporating high risk pathological factors for the prognosis of stage Ⅰ to Ⅲ colon cancer. Methods: This study retrospectively collected clinicopathological information and survival outcomes of stage Ⅰ~Ⅲ colon cancer patients who underwent curative surgery in 7 tertiary hospitals in China from January 1, 2016 to December 31, 2017. A total of 1 650 patients were enrolled, aged (M(IQR)) 62 (18) years (range: 14 to 100). There were 963 males and 687 females. The median follow-up period was 51 months. The Cox proportional hazardous regression model was utilized to select high-risk pathological factors, establish the nomogram and scoring system. The Bootstrap resampling method was utilized for internal validation of the model, the concordance index (C-index) was used to assess discrimination and calibration curves were presented to assess model calibration. The Kaplan-Meier method was used to plot survival curves after risk grouping, and Cox regression was used to compare disease-free survival between subgroups. Results: Age (HR=1.020, 95%CI: 1.008 to 1.033, P=0.001), T stage (T3:HR=1.995,95%CI:1.062 to 3.750,P=0.032;T4:HR=4.196, 95%CI: 2.188 to 8.045, P<0.01), N stage (N1: HR=1.834, 95%CI: 1.307 to 2.574, P<0.01; N2: HR=3.970, 95%CI: 2.724 to 5.787, P<0.01) and number of lymph nodes examined (≥36: HR=0.438, 95%CI: 0.242 to 0.790, P=0.006) were independently associated with disease-free survival. The C-index of the scoring model (model 1) based on age, T stage, N stage, and dichotomous variables of the lymph nodes examined (<12 and ≥12) was 0.723, and the C-index of the scoring model (model 2) based on age, T stage, N stage, and multi-categorical variables of the lymph nodes examined (<12, 12 to <24, 24 to <36, and ≥36) was 0.726. A scoring system was established based on age, T stage, N stage, and multi-categorical variables of lymph nodes examined, the 3-year DFS of the low-risk (≤1), middle-risk (2 to 4) and high-risk (≥5) group were 96.3% (n=711), 89.0% (n=626) and 71.4% (n=313), respectively. Statistically significant difference was observed among groups (P<0.01). Conclusions: The number of lymph nodes examined was an independent prognostic factor for disease-free survival after curative surgery in patients with stage Ⅰ to Ⅲ colon cancer. Incorporating the number of lymph nodes examined as a multi-categorical variable into the T and N staging system could improve prognostic predictive validity.

[Analysis of prognosis and influencing factors of No. 253 lymph node metastasis in descending colon, sigmoid colon, and rectal cancer: a multicenter study]

Objectives: To analyze the influencing factors of No. 253 lymph node metastasis in descending colon cancer, sigmoid colon cancer, and rectal cancer, and to investigate the prognosis of No. 253 lymph node-positive patients by propensity score matching analysis. Methods: A retrospective analysis was performed on clinical data from patients with descending colon cancer, sigmoid colon cancer, rectosigmoid junction cancer, and rectal cancer who underwent surgery between January 2015 and December 2019 from the Cancer Hospital of the Chinese Academy of Medical Sciences, China-Japan Friendship Hospital, Peking Union Medical College Hospital, General Hospital of the Chinese People's Liberation Army, and Peking University Cancer Hospital. A total of 3 016 patients were included according to inclusion and exclusion criteria, comprising 1 848 males and 1 168 females, with 1 675 patients aged≥60 years and 1 341 patients aged<60 years. Clinical and pathological factors from single center data were subjected to univariate analysis to determine influencing factors of No. 253 lymph node metastasis, using a binary Logistic regression model. Based on the results of the multivariate analysis, a nomogram was constructed. External validation was performed using data from other multicenter sources, evaluating the effectiveness through the area under the receiver operating characteristic curve and the calibration curve. Using data from a single center, the No. 253 lymph node-positive group was matched with the negative group in a 1∶2 ratio (caliper value=0.05). Survival analysis was performed using the Kaplan-Meier method and Log-rank test. The Cox proportional hazards model was used to determine independent prognostic factors. Results: (1) The tumor diameter≥5 cm (OR=4.496,95%CI:1.344 to 15.035, P=0.015) T stage (T4 vs. T1: OR=11.284, 95%CI:7.122 to 15.646, P<0.01), N stage (N2 vs. N0: OR=60.554, 95%CI:7.813 to 469.055, P=0.043), tumor differentiation (moderate vs. well differentiated: OR=1.044, 95%CI:1.009 to 1.203, P=0.044; poor vs. well differentiated: OR=1.013, 95%CI:1.002 to 1.081, P=0.013), tumor location (sigmoid colon vs. descending colon: OR=9.307, 95%CI:2.236 to 38.740, P=0.002), pathological type (mucinous adenocarcinoma vs. adenocarcinoma: OR=79.923, 95%CI:15.113 to 422.654, P<0.01; signet ring cell carcinoma vs. adenocarcinoma: OR=27.309, 95%CI:4.191 to 177.944, P<0.01), and positive vascular invasion (OR=3.490, 95%CI:1.033 to 11.793, P=0.044) were independent influencing factors of No. 253 lymph node metastasis. (2) The area under the curve of the nomogram prediction model was 0.912 (95%CI: 0.869 to 0.955) for the training set and 0.921 (95%CI: 0.903 to 0.937) for the external validation set. The calibration curve demonstrated good consistency between the predicted outcomes and the actual observations. (3) After propensity score matching, the No. 253 lymph node-negative group did not reach the median overall survival time, while the positive group had a median overall survival of 20 months. The 1-, 3- and 5-year overall survival rates were 83.9%, 61.3% and 51.6% in the negative group, and 63.2%, 36.8% and 15.8% in the positive group, respectively. Multivariate Cox analysis revealed that the T4 stage (HR=3.067, 95%CI: 2.357 to 3.990, P<0.01), the N2 stage (HR=1.221, 95%CI: 0.979 to 1.523, P=0.043), and No. 253 lymph node positivity (HR=2.902, 95%CI:1.987 to 4.237, P<0.01) were independent adverse prognostic factors. Conclusions: Tumor diameter ≥5 cm, T4 stage, N2 stage, tumor location in the sigmoid colon, adverse pathological type, poor differentiation, and vascular invasion are influencing factors of No. 253 lymph node metastasis. No. 253 lymph node positivity indicates a poorer prognosis. Therefore, strict dissection for No. 253 lymph node should be performed for colorectal cancer patients with these high-risk factors.

[Comparison on efficacy between fascia-oriented versus vascular-oriented lateral lymph node dissection in patients with rectal cancer]

Objective: To compare the postoperative function, the short-term and long-term outcomes between fascia-oriented and vascular-oriented lateral lymph node dissection (LLND) in patients with rectal cancer. Methods: A retrospective cohort study was performed. Clinical data of patients who received total mesorectal excision (TME) with LLND at National Cancer Center, Cancer Hospital of Chinese Academy of Medical Science from January 2014 to December 2019 were retrospectively collected. Inclusion criteria were as follows: (1) rectal cancer was pathologically diagnosed, and the lower margin was below the peritoneal reflection. (2) resectable advanced rectal cancer with suspected lateral lymph node metastasis was evaluated based on rectal MRI assessment. (3) preoperative MRI showed lateral lymph node short diameter ≥5 mm and/or lymph node morphology (spike, blur, irregular) as well as heterogenous signal intensity. Lymph node shrinkage was less than 60% after receiving neoadjuvant therapy based on the reassessment of rectal MRI. (4) TME+LLND surgery was performed synchronously. Exclusion criteria were as follows: (1) previous history of pelvic surgery; (2) preoperative cystitis, urethritis, moderate and severe prostatic hyperplasia and other diseases resulting in abnormal urination function; (3) preoperative sexual dysfunction or loss of function; (4) patients receiving LLND due to lateral recurrence after TME; (5) distant metastasis of the tumor at initial diagnosis; (6) Incomplete collection of clinical data. A total of 73 consecutive patients were enrolled in this study. Based on the surgical approaches in performing LLND, patients were divided into fascia-oriented group (n=30) and vascular-oriented group (n=43). There were no significant differences in baseline data between the two groups (all P>0.05). The main outcome indicators of this study were the incidence of postoperative urinary and male sexual dysfunction, the efficacy, the number of lateral lymph nodes harvested and the detection rate of positive lymph nodes. Overall survival (OS) rates and progression free survival (PFS) rates were calculated by the Kaplan-Meier method and compared by log-rank test. Results: All patients in both groups completed surgery successfully. There were no significant differences in operation time, intraoperative blood loss, postoperative complications, and the length of hospital stay between the two groups (all P>0.05). In the whole group, the incidence of postoperative urinary dysfunction and male sexual dysfunction was 43.8% (32/73) and 62.5% (25/40), respectively. The median number of lateral lymph nodes harvested was 8.0(4.0,11.0) with a positive rate of 20.5%(15/73). Compared to the vascular-oriented group, the fascia-oriented group demonstrated a decreased rate of urinary dysfunction [26.7% (8/30) vs. 55.8% (24/43), χ(2)=6.098, P=0.014], lower rate of sexual dysfunction in males [6/15 vs. 76% (19/25), χ(2)=5.184, P=0.023], more harvested lateral lymph nodes [M (P25, P75): 9.5 (6.8, 15.3) vs. 6.0 (3.0, 9.0), Z=-2.849, P=0.004]. There was no significant difference in the positvie rate of lateral lymph nodes between the two groups [20% (6/30) versus 20.9% (9/43), χ(2)=0.009, P=0.923]. Three(4.1%) patients were lost during a median follow-up of 34 (1-66) months. The 3-year PFS and OS of the whole cohort were 69.5% and 88.3%, respectively. No significant difference in 3-year PFS rates (79.6% vs. 62.0%, P=0.172) and 3-year OS rates (91.2% vs. 85.9%, P=0.333) were observed between the fascia-oriented group and the vascular-oriented group (both P>0.05). Conclusion: Fascia-oriented LLND is associated with lower risk of postoperative urinary and male sexual dysfunction in patients with rectal carcinoma, and harvest of more lymph nodes, but no significant advantage in long-term survival.

Purification of native myosin filaments from muscle

Analysis of the structure and function of native thick (myosin-containing) filaments of muscle has been hampered in the past by the difficulty of obtaining a pure preparation. We have developed a simple method for purifying native myosin filaments from muscle filament suspensions. The method involves severing thin (actin-containing) filaments into short segments using a Ca(2+)-insensitive fragment of gelsolin, followed by differential centrifugation to purify the thick filaments. By gel electrophoresis, the purified thick filaments show myosin heavy and light chains together with nonmyosin thick filament components. Contamination with actin is below 3.5%. Electron microscopy demonstrates intact thick filaments, with helical cross-bridge order preserved, and essentially complete removal of thin filaments. The method has been developed for striated muscles but can also be used in a modified form to remove contaminating thin filaments from native smooth muscle myofibrils. Such preparations should be useful for thick filament structural and biochemical studies.

Glucose transporter gene expression in bovine mammary gland

Transport of glucose across the plasma membrane of mammary epithelial cells is believed to be a passive process of facilitated diffusion mediated by facilitative glucose transporter(s). This article presents three lines of evidence that indicate the expression of sodium/glucose cotransporter (SGLT1) in the mammary gland of lactating and nonlactating cows. First, transcripts of SGLT1 mRNA ranging in size from 1.5 to 5.2 kb were detected in polyadenylated RNA preparations of mammary glands of lactating and nonlactating cows. Second, SGLT1 cotransporter protein was also detected in plasma membrane preparations of mammary glands of lactating cows. Third, partial amino acid sequence deduced from the reverse transcriptase-PCR fragment of SGLT1 from bovine mammary glands was similar to the sequence reported for ovine SGLT1. We conclude that mammary gland expression of SGLT1 mRNA and protein suggests that an active glucose transport system may be involved in glucose transport and metabolism in the mammary gland of dairy cows. However, the physiological significance of the expression of SGLT1 in mammary gland remains unknown.

Glucose transporter gene expression in lactating bovine gastrointestinal tract

Absorption of glucose from the intestine and probably from various portions of the gastrointestinal tract (GIT) in lactating dairy cows can have profound implications because the availability of glucose, or glucose precursors, seems to be a limiting factor for milk synthesis. This article reports on the expression of the Na+/glucose cotransporter gene (SGLT1) in mucosal tissues from rumen, omasum, abomasum, duodenum, jejunum, ileum, and cecum of lactating cows. Sodium/glucose cotransporter mRNA transcripts were detected in polyadenylated RNA of all the GIT tissues examined and in total RNA from rumen, omasum, duodenum, jejunum, ileum, and cecum. The pattern of SGLT1 mRNA distribution in these tissues was different from that of the facilitative glucose transporter GLUT5. Sodium/glucose cotransporter protein was also detected in small intestinal membranes of lactating dairy cows. Sodium-dependent glucose uptake across small intestinal brush border membrane vesicles could be resolved into linear nonsaturable (diffusion) and saturable, carrier-mediated components. The diffusion constant of glucose from jejunal membrane vesicles was 18.3+/-2.1 pmol x mM(-1) x mg protein(-1) x s(-1). The saturable component of glucose uptake had a Vmax of 27.1+/-5.8 pmol x mg protein(-1) x s(-1) and a Km of .12+/-.05 mM. Similar transport kinetics were found in the duodenum, and they were less in the ileum. These data suggest that the GIT of lactating cows is capable of active transport of glucose from the lumen across the brush border membrane of the epithelial cells. In addition, the relatively high abundance of SGLT1 mRNA in the rumen, omasum, and cecum may imply new functional and nutritional roles for these tissues in the active transport of glucose.

Pharmacokinetics of a Chinese traditional medicine, danshensu (3,4-dihydroxyphenyllactic acid), in rabbits using high-performance liquid chromatography

An injectable solution of Danshen was prepared and its in vivo disposition was examined in rabbits. The presence of Danshensu, one of the active components of Danshen, in the obtained solution was confirmed by a simple high-performance liquid chromatographic (HPLC) method. The pharmacokinetics of Danshensu in rabbits was evaluated by the HPLC method for plasma Danshensu. The calibration curve for Danshensu was linear (r = 0.998) over the concentration range of 0.25-40.0 micrograms/ml. The intra-assay coefficients of variation (CVs) were 3.8, 3.1, and 3.1% at 1, 10, and 50 micrograms/ml, respectively, and the inter-assay CVs were 5.3, 5.3, and 2.9% at 1, 10, and 50 micrograms/ml, respectively. The analytical recovery of Danshensu in plasma averaged 95.2%. From the plasma concentration profile of Danshensu after its intravenous administration, the t1/2, mean residence time (MRT), Vdss, and Cltot were determined as 32 min, 48 min, 149 ml/kg, and 3.13 ml/min/kg, respectively.

Regulation of the gene expression of glucose transporter in liver and kidney of lactating cows by bovine growth hormone and bovine growth hormone-releasing factor

Our objective was to study the effects of recombinant bovine growth hormone and bovine growth hormone-releasing factor on gene expression of glucose transporters in the liver and kidney of lactating cows. Primiparous cows received 29 mg/d of bovine growth hormone or 12 mg/d of bovine growth hormone-releasing factor by continuous intravenous infusion or no treatment (control) from 118 to 181 d postpartum. Growth hormone or growth hormone-releasing factor did not influence the mRNA abundance of the liver-type glucose transporter in the liver or kidney. Similarly, neither growth hormone-releasing factor nor growth hormone altered the mRNA abundance of the erythrocyte-type or the intestinal-type glucose transporter in the kidney, but large individual differences were observed in the mRNA abundance of the intestinal-type glucose transporter in liver.

Localization and gene expression of glucose transporters in bovine mammary gland

Glucose uptake in the mammary gland is a rate-limiting step in milk synthesis. To study glucose transporters in the bovine mammary gland, the erythrocyte-type glucose transporter (GLUT1) and the insulin-responsive glucose transporter (GLUT4) proteins were assessed by Western blotting and immunohistochemical staining, using polyclonal antibodies against the C-terminal peptide of GLUT1 and GLUT4. Our results demonstrated that the bovine mammary gland expressed a relatively high level of GLUT1 protein, whereas GLUT4 protein was not detected in the mammary gland of either lactating or dry cows. The absence of GLUT4 may indicate that glucose transport is not regulated by insulin in the lactating and dry bovine mammary gland. The anti-GLUT1 antibody strongly stained the single layer of epithelial cells of mammary alveoli. The expression of GLUT1 mRNA was similar in the mammary gland of late lactation and non-lactating cows. However, a smaller molecular weight species (38 kDa) of GLUT1 protein was detected in the mammary gland of non-lactating cows where its abundance in crude membrane preparation was 80% higher than in lactating animals. There were no significant differences in GLUT1 mRNA in bovine mammary gland at 118 d and 181 d postpartum, however, GLUT1 protein expression tended to be greater at 118 d postpartum.

Regulation of glucose transporter gene expression in mammary gland, muscle, and fat of lactating cows by administration of bovine growth hormone and bovine growth hormone-releasing factor

Primiparous cows received 29 mg of bovine growth hormone (bGH)/d, or 12 mg of bovine growth hormone-releasing factor (bGHRF)/d by continuous i.v. infusion, or no treatment (controls) from 118 to 181 d postpartum. Compared with controls, bGHRF and bGH did not influence the amount of erythrocyte-type glucose transporter (GLUT1) protein in the mammary gland; however, GLUT1 mRNA was increased (P < .01) by bGHRF, but not by bGH. The insulin-responsive glucose transporter (GLUT4) mRNA in skeletal muscle was decreased by 44% (P < .05) as a result of bGH treatment, but there was no significant effect of bGHRF. The GLUT4 mRNA was barely detectable in the omental fat of control cows and became undetectable in bGH-and bGHRF-treated cows. The results of the present study indicate that bGH and bGHRF may increase glucose availability to the mammary gland by regulating glucose transporter expression in skeletal muscle and omental fat. Our data also indicate that the galactopoietic action of bGHRF may not be mediated solely through GH.

Distribution of mammalian facilitative glucose transporter messenger RNA in bovine tissues

1. The complementary DNA for five human facilitative glucose transporters (GLUT1, GLUT2, GLUT3, GLUT4 and GLUT5) were used to determine the distribution of facilitative glucose transporter mRNA in bovine tissues by Northern blotting. Under high stringency hybridization conditions, a single 2.8 kb transcript of GLUT1 was seen in all bovine tissues examined except liver. Mammary gland had the highest abundance of GLUT1 mRNA. 2. Four GLUT2 transcripts of 6.3, 3.8, 2.2 and 1.6 kb were observed to be most abundant in liver, with lower abundance in kidney and duodenum. 3. Only a very low level of GLUT3 mRNA was detected in the mammary gland, skeletal muscle and duodenum. 4. Skeletal muscle contained the greatest abundance of GLUT4 mRNA, which was barely detectable in omental fat, kidney and mammary gland. 5. Transcripts of GLUT5 mRNA were detected in relatively high abundance in liver and kidney, and in lower abundance in the duodenum and mammary gland. 6. With the exception of the mammary gland, for which human data have not been reported, the distributions of GLUT1, 2 and 4 mRNA for the bovine tissues examined are similar to that reported for humans. On the other hand, the distributions of GLUT3 and 5 mRNA in the bovine differ from those reported for humans.

Accumulation of glutamate is regulated by calcium and protein kinase C in rat hippocampal slices exposed to ischemic states

There is now convincing evidence that excessive accumulation of the excitatory amino acid glutamate (Glu) in the extracellular space is toxic to neurons. However, the regulation of the release and uptake of Glu in producing this toxic concentration has not been adequately ascertained. The authors report that in hippocampal slices, the output of Glu significantly increased under in vitro ischemic states. Glu in the extracellular space increased fivefold. Since daurisoline, a drug that blocks N-type Ca2+ channels, or Ca(2+)-free solution potently and effectively lowered this stimulated output, it was hypothesized that the Glu output is mediated by Ca2+ influx in nerve terminals. When the slices were incubated for 30 minutes under ischemic state, daurisoline caused only small alterations in the postischemic accumulation of Glu. However, Glu accumulation was markedly attenuated by H-7, but not by calmidazolium, facilitated by PDB whereas 8-bromo-cAMP was without effect. It appears therefore that during a 30-minute ischemic insult, protein kinase C (PKC) was involved in the Glu accumulation of supernatant. A direct demonstration of this concept was obtained by showing significant increases in PKC activation in presynaptic nerve terminals (from 1.34 +/- 0.1 to 9.34 +/- 0.89 U) following 30 minutes of ischemia. DNQX, a non-NMDA receptor antagonist, potently reduced PKC activities and decreased extra Glu accumulation. Also observed was the inhibition of 1-[3H]-Glu uptake into synaptosomes by PDB. These results provide direct evidence that Ca2+ influx enhances Glu release, which in turn leads to inhibition of its reuptake, and is coupled with PKC activities in presynaptic nerve terminals.

Effects of Ca2+ antagonists on glutamate release and Ca2+ influx in the hippocampus with in vivo intracerebral microdialysis

1. The extracellular glutamate content and Ca2+ level in vivo in rat hippocampus were measured by brain microdialysis following administration of two depolarizing agents (veratridine, KCl) and quinolinic acid (Quin). 2. The two depolarizing agents increased the extracellular glutamate level (to between 280 and 320% basal) and decreased the extracellular Ca2+ content (to 48% of basal). However, Quin did not change the glutamate level but decreased the Ca2+ content. 3. The effects of Ca2+ antagonists on the changes of glutamate and Ca2+ level were evaluated in this experimental model. At a dose of 0.5 mg kg-1, i.v., nimodipine (L-type channel blocker) did not produce significant changes in the stimulated-glutamate release. A statistically significant inhibition of Ca2+ influx was observed at a dose of 0.05 mg kg-1. In contrast, in those animals receiving the N-type Ca2+ antagonist, daurisoline (0.1, 1 or 5 mg kg-1, i.v.), a potent attenuation of both glutamate release and Ca2+ influx was found. 4. We propose that the pharmacological properties of Ca2+ influx and of neurotransmitter release differ and that nimodipine-sensitive L-type channels may not be very common in nerve terminals but are localized in cell soma. Daurisoline-sensitive N-type channels in nerve terminals have a much greater influence on excitatory amino acid release.

Effects of nimodipine on l-glutamate-induced seizures and Ca2+ influx in hippocampus in freely moving rats

Seizure (EEG) was studied in rats unilaterally injected in the dorsal hippocampus with l-glutamate (Glu). Extracellular Ca2+ content [(Ca2+)e] in the injected area was assessed by brain microdialysis coupled to automatic atomic absorption spectrophotometry. In this experimental epileptic model, an inhibition of Glu-stimulated epileptic activity and a fall in (Ca2+)e by nimodipine (Nim, 100 micrograms.kg-1) were seen. The spike- and wave-burst frequency was reduced from 30 to 5 bursts.min-1 (P less than 0.01, n = 8). Nim 25 and 50 micrograms.kg-1, without anticonvulsant activity, did not prevent the drop in (Ca2+)e. These results indicate that Nim exerts an antiepileptic effect on Glu-induced epilepsy. The mechanisms may be involved in blocking Ca2+ influx into neurons.