[Inhibitive effects of Panax notoginseng saponins on expression of Abeta(1-40), Abeta(1-42) protein in SAMP8's brain].

OBJECTIVE: To observe inhibitive effects of Panax notoginseng saponins on expression of Abeta(1-40), Abeta(1-42) protein in SAMP8's brain. METHODS: Amount of Abeta(1-40), Abeta(1-42 immuno-positive neurons was detected in parietal cortex and hippocamp in their brains under high power lens (40 x) by immunohistochemistry analysis. RESULTS: PNS could reduce the amount of Abeta(1-40), Abeta(1-42) protein in parietal cortex and hippocamp. CONCLUSION: PNS can reduce the amount of Abeta(1-40), Abeta(1-42) protein in SAMP8's brain.

[5-HT1A/1B receptors, alpha2-adrenoceptors and the post-receptor adenylate cyclase activation in the mice brain are involved in the antidepressant-like action of agmatine].

This study is to explore the possible mechanisms of the antidepressant-like effect of agmatine. By using two traditional "behavior despair" model, tail suspension test and forced swimming test, we examined the effects of some monoamine receptor antagonists (including beta-adrenergic receptor antagonist propranolol, beta-adrenergic receptor antagonist/5-HT1A/1B receptor antagonist pindolol, alpha2-adrenergic receptor antagonists yohimbine and idazoxan and 5-HT3 receptor antagonist tropisetron) on the antidepressant-like action of agmatine in mice. Activity of adenylate cyclase (AC) in the synapse membrane from rat frontal cortex was determined by radioimmunoassay. Single dose of agmatine (5-40 mg x kg(-1), ig) dose-dependently decrease the immobility time in tail suspension test in mice, indicating an antidepressant-like effect. The effect of agmatine (40 mg x kg(-1), ig) was antagonized by co-administration of beta-adrenergic receptor antagonist/5-HT1A/1B receptor antagonist pindolol (20 mg x kg(-1), ip), alpha2-adrenergic receptor antagonists yohimbine (5-10 mg x kg(-1), ip) or idazoxan (4 mg x kg(-1), ip), but not beta-adrenergic receptor antagonist propranolol (5-20 mg x kg(-1), ip) and 5-HT3 receptor antagonist tropisetron (5-40 mg x kg(-1), ip). Agmatine (5-40 mg x kg(-1), ig) also dose-dependently decrease the immobility time in forced swimming test in mice. The effect of agmatine (40 mg x kg(-1), ig) was also antagonized by pindolol (20 mg x kg(-1), ip), yohimbine (5-10 mg x kg(-1), ip), or idazoxan (4 mg x kg(-1), ip). Incubation of agmatine (0.1-6.4 micromol x L(-1)) with the synaptic membrane extracted from rat frontal cortex activated the AC in a dose-dependent manner in vitro. While the effect of agmatine (6.4 micromol x L(-1)) was dose-dependently antagonized by pindolol (1 micromol x L(-1)) or yohimbine (0.25-1 micromol x L(-1)). Chronic treatment with agmatine (10 mg x kg(-1), ig, bid, 2 w) or fluoxetine (10 mg x kg(-1), ig, bid, 2 w) increased the basic activity, as well as the Gpp (NH)p (1-100 micromol x L(-1)) stimulated AC activity in rat prefrontal cortex. These results indicate that regulation on 5-HT1A/1B and alpha2 receptors, and activation AC in the frontal cortex is one of the important mechanisms involving in agmatine's antidepressant-like action.

[Effects of ginkgolides on gene expression of hepatic cytochrome P-450 in rats].

OBJECTIVE: To observe the effects of ginkgolides on gene expression of hepatic cytochrome P-450 in rats. METHOD: Sprague-Dawley rats were administered ginkgolides (100 mg x kg(-1) body weight) through oral gavage once daily for four consecutive days. The level of gene expression in liver tissues was analyzed by competitive reverse transcription-polymerase chain reaction (competitive RT-PCR). RESULT: A single and prospective band of CYP1A1, CYP1A2, CYP2B1/B2, CYP2C11, CYP2E1, CYP4A1 and cyclophilin was observed after polymerase chain reaction (PCR) when the reactive system of reverse transcription (RT) had no target RNA, which confirmed the competitor had a specific capacity to bind to the CYP or cyclophilin primer. CYP1A1 mRNA was not dectectable in the livers of untreated control rats and ginkgolides-treated rats. The levels of CYP2C11 and CYP2E1 were not changed by ginkgolides treatment. In contrast, the levels of gene expression for CYP1A2 and CYP2B1/B2 were decreased, however, the levels of gene expression for CYP3A1 and CYP4A1 in ginkgolides group were distinctly increased compared with the control. CONCLUSION: A specific effect of ginkgolides on cytochrome P-450 gene expression was observed in this investigation. Ginkgolides had various effects on different cytochrome P-450 isoforms.

[Effects of the Panax notoginseng saponins on the level of synaptophysin protein in brain in rat model with lesion of Meynert].

OBJECTIVE: To observe the protective effect of Panax notoginseng saponins (PNS) on the level of synaptophysin ptotein in brain in rat model with Alzheimer's disease (AD). METHOD: The AD rat models were established by intra-peritoneal injection of D-galactose combined with excitatory neurotoxin ibotenic acid injection into bilateral nbM. The activity and content of synaptophysin protein in brain were determined by immunohistochemistry analysis. RESULT: PNS could reduce the lesion of level of synaptophysin protein in brain, as compared with those of model group's rats. CONCLUSION: PNS plays a protective role by reducing down of the level of synaptophysin protein in brain in lesion of AD animal model.

[The anticancer effect of artesunate and its mechanism].

AIM: To study the anticancer effect of artesunate and its mechanism. METHODS: To observe the effect of artesunate on the growth of solid tumor and the expression of PCNA, Bcl-2 and Bax genes in mice bearing H22 solid hepatic carcinoma. RESULTS: After administration of artesunate (ig, 300 mg.kg-1.d-1 x 7 d), growth of solid tumor was obviously inhibited, the tumor inhibitory rates were 49.1%, 48.7% and 46.6% and 46.6% in 3 experiments. The apoptosis of liver cancer cells were increased. Immunohistochemical staining showed that the number of Bcl-2 protein positive cells were decreased, but the number of Bax protein positive cells were increased. The PCNA positive cells were significantly lower than those in the control group. CONCLUSION: Artesunate showed obvious anticancer activity on H22 hepatic carcinoma bearing mice and undergo apoptosis of liver cancer cells. The mechanism of anticancer effect of artesunate may be related to down-regulation of the expression of PCNA and Bcl-2 genes and up-regulation of the expression of Bax gene.

[Effects of the active components of some Chinese herbs on drug metabolizing-enzymes].

OBJECTIVE: To review the effects of the active components of Chinese herbs on drug metabolizing-enzymes. METHOD: Relevant research papers reported in recent years were consulted and studied. RESULT: The drug metabolizing-enzymes cytochrome P450 and UDP-glucuronosyl transferase and glutathione S-transferase were inhibited or induced by the flavonoids, furocoumarins, and the active components extracted from salvia miltiorrhiza and hypericum perforatum, and so on, which therefore slowed or sped metabolism of other drugs in vivo and in vitro. CONCLUSION: Much attention should be paid to the metabolic interaction of the Chinese herbs when coadministered with other drugs.

[Study on reliability and validity of the Tinnitus Evaluation Questionnaire].

OBJECTIVE: To investigate the value of the Tinnitus Evaluation Questionnaire (TEQ) in clinical application. METHODS: Cronbach's α coefficient was used to examine the reliability of the TEQ internal consistency. Examined the re-measured reliability by the correlation coefficient by two doctors' 1 - 3 hours interval questionnaires' scores. And inspected criteria validity according to the correlation coefficient of the TEQ and Tinnitus Handicap Inventory (THI). RESULTS: In the 202 tinnitus patients, the TEQ Cronbach's α coefficient was 0.76 and re-measured reliability was 0.938. The THI correlation coefficient was 0.769. Among which, 99 patients feel tinnitus alleviated obviously after the treatment, the TEQ scores were significantly lower than that before the treatment (t = 21.42, P < 0.001). CONCLUSIONS: The TEQ reflects the severity of tinnitus completely, and has preferable reliability and validity. The characteristics are concise, practical and exact. It is worthy of clinical application.

Effects of Ginkgo biloba extract and tanshinone on cytochrome P-450 isozymes and glutathione transferase in rats.

AIM: To investigate the effects of Ginkgo biloba extract (GbE) and tanshinone (Tan) on cytochrome P450 (CYP) isozymes and glutathione transferase (GT) in rats. METHODS: Several CYP-dependent reactions were monitored in liver and kidney microsomes of male rats treated ig with GbE and Tan daily for 10 d. The activity of GT, the levels of malondialdehyde (MDA) and nitric oxide (NO) in the tissues were also determined. RESULTS: CYP1A1, 1A2, and 2B1 activities in the liver were all significantly increased (2-9.5 fold) by pretreatment with GbE or Tan (P<0.01). An induction (1.4 fold) of CYP 2E1 activity was observed at the higher dose of GbE treatment (P<0.01), but a reduction (1.9 fold) after Tan administration (P<0.01). Whereas GbE could induce CYP3A (1.6 fold) (P<0.01) but Tan had no effects. Furthermore, the activities of CYP 1A1 (5.6-8.9 fold) and 1A2 (2.6 fold) in the kidney were induced by GbE (P<0.01). The activity of GT in rat liver receiving Tan was significantly increased (P<0.05) and a dramatic reduction in the activity of GT in the kidney was observed in the GbE-treated group (P<0.01). In addition, the GbE treatment markedly decreased the levels of MDA and NO in the tissues of rats (P<0.01). CONCLUSION: The modulation of CYP isozymes by GbE and Tan may result in altered metabolism of coadministered drugs. In addition, GbE is an active antioxidant and nitric oxide inhibitor in vivo.