Increased ghrelin signaling prolongs survival in mouse models of human aging through activation of sirtuin1.

Caloric restriction (CR) is known to retard aging and delay functional decline as well as the onset of diseases in most organisms. Ghrelin is secreted from the stomach in response to CR and regulates energy metabolism. We hypothesized that in CR ghrelin has a role in protecting aging-related diseases. We examined the physiological mechanisms underlying the ghrelin system during the aging process in three mouse strains with different genetic and biochemical backgrounds as animal models of accelerated or normal human aging. The elevated plasma ghrelin concentration was observed in both klotho-deficient and senescence-accelerated mouse prone/8 (SAMP8) mice. Ghrelin treatment failed to stimulate appetite and prolong survival in klotho-deficient mice, suggesting the existence of ghrelin resistance in the process of aging. However, ghrelin antagonist hastened death and ghrelin signaling potentiators rikkunshito and atractylodin ameliorated several age-related diseases with decreased microglial activation in the brain and prolonged survival in klotho-deficient, SAMP8 and aged ICR mice. In vitro experiments, the elevated sirtuin1 (SIRT1) activity and protein expression through the cAMP-CREB pathway was observed after ghrelin and ghrelin potentiator treatment in ghrelin receptor 1a-expressing cells and human umbilical vein endothelial cells. Furthermore, rikkunshito increased hypothalamic SIRT1 activity and SIRT1 protein expression of the heart in the all three mouse models of aging. Pericarditis, myocardial calcification and atrophy of myocardial and muscle fiber were improved by treatment with rikkunshito. Ghrelin signaling may represent one of the mechanisms activated by CR, and potentiating ghrelin signaling may be useful to extend health and lifespan.

Administration of exogenous acylated ghrelin or rikkunshito, an endogenous ghrelin enhancer, improves the decrease in postprandial gastric motility in an acute restraint stress mouse model.

BACKGROUND: Physical or psychological stress causes functional disorders in the upper gastrointestinal tract. This study aims to elucidate the ameliorating effect of exogenous acylated ghrelin or rikkunshito, a Kampo medicine which acts as a ghrelin enhancer, on gastric dysfunction during acute restraint stress in mice. METHODS: Fasted and postprandial motor function of the gastric antrum was wirelessly measured using a strain gauge force transducer and solid gastric emptying was detected in mice exposed to restraint stress. Plasma corticosterone and ghrelin levels were also measured. To clarify the role of ghrelin on gastrointestinal dysfunction in mice exposed to stress, exogenous acylated ghrelin or rikkunshito was administered, then the mice were subjected to restraint stress. KEY RESULTS: Mice exposed to restraint stress for 60 min exhibited delayed gastric emptying and increased plasma corticosterone levels. Gastric motility was decreased in mice exposed to restraint stress in both fasting and postprandial states. Restraint stress did not cause any change in plasma acylated ghrelin levels, but it significantly increased the plasma des-acyl ghrelin levels. Administration of acylated ghrelin or rikkunshito improved the restraint stress-induced delayed gastric emptying and decreased antral motility. Ameliorating effects of rikkunshito on stress-induced gastric dysfunction were abolished by simultaneous administration of a ghrelin receptor antagonist. CONCLUSIONS & INFERENCES: Plasma acylated/des-acyl ghrelin imbalance was observed in acute restraint stress. Supplementation of exogenous acylated ghrelin or enhancement of endogenous ghrelin signaling may be useful in the treatment of decreased gastric function caused by stress.

The relationship between consumption of antimicrobial agents and the prevalence of primary Helicobacter pylori resistance.

BACKGROUND: Primary and acquired resistance to the antimicrobial agents is a primary reason for the failure of Helicobacter pylori eradication therapies. We assessed the primary antibiotic resistance rates of H. pylori to three different antibiotics and its relationship due to the annual antibiotic consumption in Japan during the period prior to approval of anti-H. pylori therapy in Japan. MATERIALS AND METHODS: Antibiotic susceptibility was tested using the agar dilution method for clarithromycin, amoxicillin and metronidazole. Isolates were considered resistant when the MIC value was > 8 mg/l for metronidazole, > 1 mg/l for clarithromycin and < 0.5 mg/l for amoxicillin. RESULTS: Helicobacter pylori isolates were obtained from 593 Japanese patients from 1995 to 2000. Primary resistance of H. pylori to clarithromycin, metronidazole and amoxicillin was found in 11%, 9% and 0.3% strains, respectively. The proportion with clarithromycin resistance significantly increased from 7% in 1997-98 to 15.2% in 1999-2000 (p =.003). During the same period the metronidazole resistance rate also increased from 6.6% in 1997-98 to 12% in 1999-2000 (p =.02). The prevalence of clarithromycin and metronidazole was related to the annual consumption of these antimicrobial agents. CONCLUSION: Resistance rates for both clarithromycin and metronidazole appear to reflect the annual consumption of these agents. The high rate of clarithromycin resistance in Japan suggests that the effectiveness of clarithromycin-based therapies may be compromised in the near future.

Protective effects of Saiko-ka-ryukotsu-borei-to (Chai-Hu-Jia-Long-Gu-Mu-Li-Tang) against atherosclerosis in Kurosawa and Kusanagi-hypercholesterolemic (KHC) rabbits.

We investigated the protective effects of the traditional Japanese herbal medicine Saiko-ka-ryukotsu-borei-to (Chai-Hu-Jia-Long-Gu-Mu-Li-Tang in Chinese) (SRBT) against hypercholesterolemia and atherosclerotic lesions. We focused on atherosclerosis using female heterozygous Kurosawa and Kusanagi-hypercholesterolemic (KHC) rabbits. The total plasma cholesterol levels increased for up to 12 weeks after beginning a diet containing 0.1% cholesterol and then reached a plateau of about 600 mg dl(-1). When SRBT was administered at a dose of 1.0 g kg(-1)per day for 24 weeks, total plasma cholesterol levels were significantly decreased after 20-24 weeks. On the other hand, pravastatin at a dose of 10 mg kg(-1)per day produced a significant decrease in total plasma cholesterol levels from 4 to 24 weeks (about 105-130 mg dl(-1)). Moreover, 1.0 g kg(-1)per day of SRBT significantly decreased plasma low density lipoprotein (LDL) cholesterol levels but did not change either very low density lipoprotein (VLDL), or high density lipoprotein (HDL) cholesterol levels. Animals that received pravastatin had significantly decreased LDL cholesterol levels and VLDL cholesterol levels after 8 weeks and at 24 weeks. We also examined the expression of apoB, E and LDL receptor mRNA levels in the liver at 24 weeks after beginning the administration of 1.0 g kg(-1)per day of SRBT. Both apoE and LDL receptor mRNA levels were significantly increased compared with those in rabbits receiving the 0.1% cholesterol diet. SRBT at a dose of 1.0 g kg(-1)per day significantly depressed the intimal surface area of the thoracic aortae involved with atheromatous plaques. The present results suggest that SRBT may protect against hypercholesterolemia and atheromatous lesions by affecting apoE and LDL receptor mRNA gene expression in the liver.

[Comparison between real-time pollen monitor KH-3000 and Burkard sampler].

Special apparatus capable of instantly measuring airborne Cryptomeria japonica pollen grains were recently appeared on the market. We examined one of them called real-time pollen monitor KH-3000 (Yamato Manufacturing Co. Ltd.). To confirm the accuracy of the monitor, comparison was made with conventional Burkard Seven-Day Recording Volumetric Spore Trap operating simultaneously at the same place. Most peaks from KH-3000 were coincided with Cry j 1 from Burkard sampler, and the greater part of the counts from KH-3000 had a strong resemblance to the counts from Cry j 1. Therefore, it is confirmed that KH-3000 counts the numbers of airborne C. japonica pollen grains. KH-3000 sometimes counts particles which do not belong to pollen grains, however. It is also confirmed that some pollens other than C. japonica, such as walnut (Juglans spp.) pollen, a part of grass pollen were counted.

High-dose ecabet sodium improves the eradication rate of helicobacter pylori in dual therapy with lansoprazole and amoxicillin.

AIM: The additive effect of ecabet sodium in combination with dual therapy on Helicobacter pylori eradication was evaluated. METHODS: H. pylori-positive chronic gastritis patients were randomly assigned to one of the following three groups and medicated for 2 weeks. Group LA: dual therapy (lansoprazole 30 mg o.d. plus amoxicillin 750 mg b.d.). Group LA1E: dual therapy plus ecabet sodium (1 g b.d.). Group LA2E: dual therapy plus ecabet sodium (2 g b.d.). Patients were evaluated 4 weeks after the cessation of treatment by culture and 13C-urea breath test. RESULTS: Seventy-one patients (mean age, 56.6 years; range, 26-79 years; 40 males, 31 females) were enrolled in this prospective, single-blind study, and 68 completed the protocol. The eradication rates per protocol patient were 43% in group LA, 62% in group LA1E, and 79% in group LA2E, and those on the intention-to-treat basis were 42% in group LA, 57% in group LA1E and 79% in group LA2E. The eradication rate in group LA2E was significantly higher than group LA (P=0.032 in per protocol, P=0.022 in intention-to-treat). Adverse effects were observed in 10 patients in this study. There were no severe adverse effects caused by ecabet sodium. CONCLUSION: High-dose ecabet sodium increases eradication rates of H. pylori in dual therapy with lansoprazole and amoxicillin.

Induction of apoptosis by Acanthopanax senticosus HARMS and its component, sesamin in human stomach cancer KATO III cells.

Antitumor effect of the stem bark of Acanthopanax senticosus HARMS (ASH) from Hokkaido (Japanese name: Ezoukogi) on human stomach cancer KATO III cells was investigated. The extract of the stem bark of ASH prepared with hot water was dissolved in distilled water and used for the assay of antitumor effect on the KATO III cells. The exposure of KATO III cells to ASH led to both growth inhibition and induction of apoptosis. Morphological change showing apoptotic bodies was observed in the cells treated with ASH. The fragmentation by ASH of DNA to oligonucleosomal-sized fragments that are characteristics of apoptosis was observed to be concentration- and time-dependent. We have investigated which component in ASH is effective on the induction of apoptosis. Among chlorogenic acid, syringaresinol di-o-beta-D glucoside, syringin, and sesamin, components of the n-butanol extract prepared from ASH, sesamin suppressed the growth and induced apoptosis in the cells. These findings suggest that growth inhibition by ASH results from the apoptosis induced by sesamin, a component of ASH.

Antioxidative effects of Choi-oki-to and its ability to inhibit the progression of atheroma in KHC rabbits.

Agents which inhibit the oxidative modification of low density lipoprotein (LDL) have been thought to be helpful in preventing the formation of atherosclerotic lesions; the so called "oxidation hypothesis". To test this hypothesis, we examined the antioxidative activities of 127 Kampo medicines in vitro and their inhibitory effects on the development of atheromatous plaque formation in KHC rabbits, a model of spontaneous familial hypercholesterolemia. Some of the 127 Kampo medicines showed scavenging or antioxidative effects equal to or stronger than those of probucol in vitro. Choi joki to, which had the strongest antioxidative effects on LDL in vitro, was chosen for a study in vivo. After 24 weeks, 1 g/kg of Choi joki to successfully inhibited the progression of atherosclerotic lesions in KHC rabbits (P < 0.01). Further investigations regarding the antioxidative effects of Kampo medicines are expected.

Effects of San'o-shashin-to on the antioxidative mechanism in spontaneous familial hypercholesterolaemic rabbits.

We investigated the effects of the Kampo medicine San'o-shashin-to which showed strong antioxidative effects in vitro on antioxidative mechanism in Kurosawa and Kusanagi- hypercholesterolaemic (KHC) rabbits, which are a good model of spontaneous familial hypercholesterolaemia. A 1-g kg(-1)dose of San'o-shashin-to was administered orally for 24 weeks and changes in plasma lipids, low-density lipoprotein (LDL) oxidation and redox dynamics of alpha-tocopherol in plasma and erythrocyte membrane were measured in a control group and San'o-shashin-to-treated group. A significant prolongation of the lag time was found in the 12th and 24th week of the experiment in San'o-shashin-to-treated group, indicating antioxidative effects on LDL. At the end of the administration period, the alpha-tocopherolquinone/alpha-tocopherol ratio in erythrocyte membrane, which reflects the utilization rate of alpha-tocopherol was significantly higher in San'o-shashin-to-treated group. There were no significant differences in the two groups with regards to plasma lipids. These results indicate that San'o-shashin-to had antioxidative effects on LDL in vivo and beneficial effects on redox dynamics of alpha-tocopherol, which is the strongest endogenous antioxidant.

Comparison between chemoradiation protocol intended for organ preservation and conventional surgery for clinical T1-T2 esophageal carcinoma.

PURPOSE: This retrospective study was designed to compare treatment results of the chemoradiation protocol with conventional surgery for thoracic T1-T2 esophageal squamous cell carcinoma. METHODS AND MATERIALS: Sixty-six patients with esophageal carcinoma, clinically diagnosed as T1 (tumor invading lamina propria or submucosa) or T2 (tumor invading muscularis propria) were treated for 12 consecutive years, from July 1986 to January 1998. The conventional surgery group included 30 patients who underwent esophagectomy with regional lymph node dissection. Twenty-one of them received postoperative radiotherapy. Thirty-six patients were assigned to the chemoradiation protocol, consisting of neoadjuvant chemoradiotherapy (44 Gy; CDDP: 60 mg/m2, day 1, bolus; 5-FU: 400 mg/m2, day 1-4, continuous), followed by either definitive radiotherapy with high-dose-rate intraluminal brachytherapy (total 70 Gy) for responders or surgery for nonresponders as in the conventional surgery group. Surgical candidates in both groups received intraoperative radiotherapy for abdominal lymphatics since 1991. RESULTS: In the protocol group, 4 patients underwent radical surgery after neoadjuvant chemoradiotherapy, and the remaining 32 underwent definitive chemoradiotherapy. Local control rates at 1 and 3 years were 85% and 70% in the T1/protocol group versus 91% and 80% in the T1/surgery group, and 83% and 83% in the T2/protocol group versus 94% and 80% in the T2/surgery group, respectively. There was no statistical significance. Overall 1- and 3-year survival rates were 100% and 83% in the T1/protocol group versus 82% and 72% in the T1/surgery group (p = 0.36), and 100% and 51% in the T2/protocol group, versus 95% and 68% in the T2/surgery group p = 0.61), respectively. There was no treatment-related mortality in either group. The rates of esophageal conservation were 92% in the T1/protocol group and 58% in the T2/protocol group. CONCLUSION: The chemoradiation protocol can result in comparable survival with conventional surgery for patients with T1-T2 esophageal carcinoma. A randomized trial between definitive chemoradiotherapy and surgery is required.

Neurochemical characteristics and behavioral responses to psychological stress in ovariectomized rats.

The present study was designed to clarify the time-dependent changes in brain monoamine turnover in the frontal cortex, hypothalamus, hippocampus, septum and amygdala after ovariectomy, and the difference in behavioral responses to psychological stress between sham-operated and ovariectomized (OVX) rats. At 2 and 4 weeks after ovariectomy, the turnover rates of dopamine and norepinephrine in all of the brain regions examined did not differ significantly between the sham-operated and OVX rats. However, 5-hydroxytryptamine (5-HT) turnover in all of the brain regions at 2 weeks after OVX was significantly lower than that in sham-operated rats. This difference was greater in the hypothalamus than in other brain regions. At 4 weeks after ovariectomy, 5-HT turnover in all of the brain regions examined was not significantly different between sham-operated and OVX rats. At 2 and 4 weeks after ovariectomy, exploratory behaviour (e.g., locomotor activity, head- dipping, crossing and rearing behaviours) in a non-stressed ovariectomy group did not differ from that in a non-stressed sham-operation group. Locomotor activity and the number of head-dips and crossings significantly (P<0.05) increased after repeated exposure to psychological stress for 5 days in sham-operated rats, but not in those at 2 weeks after OVX. At 4 weeks after ovariectomy, locomotor activity and the number of crossings and rearings in sham-operated and OVX rats were not significantly different in the psychological stress and non-stress groups. However, the number of head-dips significantly (P<0.05) increased with psychological stress in the sham-operated rats, but not in OVX rats. These results suggest that female gonadal hormones may play an important role in the regulation of brain 5-HTergic systems. These interactions between gonadal hormones and 5-HT metabolism may be related to 5-HT-related neuropsychiatric disorders.

Effects of Saiko-ka-ryukotsu-borei-to on irritable characteristics in El mice.

In the present study, we attempted to characterize the circadian rhythm of locomotor activity of El mice and to examine the duration of sodium pentobarbital-induced sleep during the light and dark periods. The effect of Saiko-ka-ryukotsu-borei-to, a representative Kampo medicine used for treating insomnia, was studied on the locomotor activity and on the duration of sodium pentobarbital-induced sleep in El mice. The spontaneous locomotor activity of El mice during the dark period was not so different from that of ddY mice, whereas the activity during the light period was significantly higher in the El mice, and the duration of sodium pentobarbital-induced sleep of El mice was very short during the light period, nearly equal to that during the dark period. The administration of Saiko-ka-ryukotsu-borei-to caused marked reduction in the locomotor activity during the light period, and dose-dependent prolongation in the duration of sodium pentobarbital-induced sleep time during the light period, but that during the dark period was unaffected. These findings suggest that the El mouse is a model with a tendency to be easily excitable during the light period compared to ddY mice. Furthermore, it was confirmed that Saiko-ka-ryukotsu-borei-to reduced the excitation in El mice and might be useful against sleep disorder due to excitation.

Protective effects of Hange-shashin-to on water-immersion restraint stress-induced gastric ulcers.

Hange-shashin-to (HST) is a traditional Chinese herbal prescription (Banxia Xiexin Tang) which has long been used in the therapy of gastric functional disorders. In this report, the effect of HST extract on water-immersion restraint stress-induced gastric ulcer based on the changes in gastric mucin content and the variations of monoamine contents in hypothalamus were investigated. Ulcer index was microscopically measured by the sum total of the lengths of ulcers in glandular stomach. Gastric mucin content was determined by a PAS-staining methods and the monoamine contents were detected by HPLC-ECD method. HST extract was orally administered at 1, 2 and 3 g/kg for three consecutive days before stress exposure. Water-immersion restraint stress decreased the mucin content and produced gastric ulcers in a restraint time-dependent manner. Pretreatment with HST extract markedly inhibited the reduction of gastric mucin content and the development of gastric ulcer with significant differences (p < or = 0.01). The remarkable decrease of NE and 5-HT contents but prominent increases of MHPG and 5-HIAA contents were observed in hypothalamus after water-immersion restraint stress (p < or = 0.01). Those changes in monoamine contests in hypothalamus were also significantly inhibited by the pretreatment with HST extract at higher dosage (p < or = 0.05). These results indicate that the changes in gastric mucin content and the variation of monoamines in hypothalamus relate to the pathogenesis of water-immersion restraint stress-induced gastric ulcers, and it is suggested that the prophylactic effects of HST extract on stress induced gastric ulcers may be associated with an increase in gastric mucin content, although the prevention of HST extract on the extraordinary changes in monoamine contents in hypothalamus due to stress cannot be ruled out.

Effects of Toki-shakuyaku-san on electric footshock stress in ovariectomized mice.

In the present study, ovariectomized mice were exposed to electric footshock stress for 7 days, and the duration of sodium pentobarbital-induced sleep was measured on the day following the last stress exposure. In ovariectomized mice, the duration of sodium pentobarbital-induced sleep before exposure to stress did not differ markedly from that in the sham-operation group. After exposure to stress, however, the duration of sodium pentobarbital-induced sleep in ovariectomized mice was shortened significantly, compared to the ovariectomized mice without stress. When the effect of Toki-shakuyaku-san on the stress-induced shortening of sleep time was studied, it was found that the shortening of the sleep time was suppressed by treatment with Toki-shakuyaku-san. In ovariectomized mice, the increase in hypothalamic noradrenaline (NA) turnover in response to stress was significantly greater than that in mice with intact ovaries. The stress-induced enhancement of NA turnover was suppressed significantly by Toki-shakuyaku-san in a dose-dependent manner, beginning with a low dose level. When effect of 17Beta-estradiol on the stress induced-shortening of sleep time was examined in ovariectomized mice, by high doses of 17Beta-estradiol the shortening of the sleep time was prolonged. A major difference between 17Beta-estradiol and Toki-shakuyaku-san was the marked uterine weight gain observed following 17Beta-estradiol treatment despite no effect of Toki-shakuyaku-san on uterine weight. The results in this study suggest that Toki-shakuyaku-san may reduce menopausal symptoms by a mechanism different from that of estrogen.

Neoadjuvant concurrent chemoradiotherapy followed by definitive high-dose radiotherapy or surgery for operable thoracic esophageal carcinoma.

PURPOSE: A prospective clinical trial was undertaken to investigate the feasibility of concurrent chemoradiotherapy for esophageal carcinomas. MATERIALS AND METHODS: Between June 1989 and May 1996, forty patients with operable squamous cell carcinoma of the thoracic esophagus (Stage 0 to III: UICC 1987), ages 45 to 78 years (mean: 64), were enrolled in a study of neoadjuvant concurrent chemoradiotherapy followed by definitive high-dose radiotherapy (CRT group) or surgery (CRT-S group). Neoadjuvant chemoradiotherapy consisted of 44 Gy in 40 fractions for 4 weeks (2.2 Gy/2 Fr/day) through 10-MVX rays, with 2 courses of cisplatin (80-100 mg/body, mean: 60 mg/m2, Day 1, bolus injection) and 5-fluorouracil (500-1000 mg/body/day, mean: 400 mg/m2, Days 1-4, continuous infusion). After completion of neoadjuvant chemoradiotherapy, an intermediate clinical response was assessed by barium swallow, esophagoscopy with/without biopsy, EUS in most cases, thoracic and upper abdominal CT scan, and cervical US. Definitive chemoradiotherapy was performed in patients when regression of more than 75% was evident (CRT Group), and esophageal resection was indicated in those who remained at less than 75% (CRT-S Group). In CRT Group, a cumulative dose of 60-70 Gy for Tis, T1 and 65-75 Gy for T2-T4 tumor with high-dose-rate intraluminal brachytherapy and a total of 3 courses of chemotherapy were planned. In CRT-S Group, intraoperative radiotherapy for abdominal lymphatic system and postoperative supraclavicular irradiation were added. RESULTS: At the time of intermediate assessment, complete response (CR) was observed in 16 patients, a partial response (PR) in 22, and no change (NC) in 2. Thirty responding patients (CR, 16; PR, 14) entered the CRT Group, and 10 nonresponding patients (PR, 8; NC, 2) were followed by surgery (CRT-S Group). Radiotherapy was completed satisfactorily, but chemotherapy was suspended in 26 patients (65%) because of acute toxicity. Clinical CR rate at the completion of treatment showed 90% in CRT Group, and pathologic CR rate 10% in CRT-S Group. The overall median survival was 45 months, survival at 1, 2, and 3 years being 100%, 72%, and 56%, respectively. Local-regional failure was observed in 7 patients (all in CRT Group), distant failure in 6 (3 in CRT Group, 3 in CRT-S Group) and local-regional with distant failure in 1 (CRT Group). Four patients with local-regional recurrence in the CRT Group were salvaged by surgery. Overall survival at 2 and 3 years for CRT vs. CRT-S Group was 72%, 64% vs. 75%, 38%, respectively. No treatment-related mortality was observed. The rate of the 'esophagus conservation' was 65% (Stage 0: 1 of 1, 100%; Stage I: 11 of 12, 92%; Stage II: 8 of 17, 47%; Stage III: 6 of 10, 60%). CONCLUSION: Our results demonstrated that almost all early disease (Stage 0-I) and about half of advanced disease (Stage II-III) could be conserved, their esophagus treated by the multidisciplinary approach centering on high-dose radiotherapy and concurrent chemotherapy.

Nisoldipine selectively induces coronary vasodilation and improves mild myocardial ischemia in dogs: a potential role of cellular acidosis.

We examined whether nisoldipine, a calcium (Ca) channel blocker, increases coronary blood flow (CBF) without decreasing aortic blood pressure (AoP) with ischemic and nonischemic hearts, and whether the presence of cellular acidosis in ischemic myocardium contributes to the augmentation of coronary vasodilation due to nisoldipine. In 42 dogs, coronary perfusion pressure (CPP) was reduced so that CBF decreased to 60% of the baseline, and CPP was maintained constant thereafter. First, we administered nisoldipine into a systemic vein in the ischemic and nonischemic hearts. Second, nisoldipine was administered into the canine coronary artery of the ischemic myocardium, with and without administration of either sodium bicarbonate (NaHCO3), sodium hydroxide (NaOH), or amiloride. Nisoldipine (0.25-4.0 mg/kg, i.v.) increased CBF by 59% in the ischemic myocardium more than the nonischemic myocardium (by 34%) without reducing AoP. The infusion of nisoldipine (40 ng/kg/min, IC) increased CBF markedly by about 55% in the ischemic myocardium with increases in fractional shortening (FS; 11 +/- 2% to 21 +/- 2%) and lactate extraction ratio (LER; -19 +/- 4% to 15 +/- 2%). Increases in CBF, FS, and LER were markedly attenuated during administration of nisoldipine with concomitant administration of either NaHCO3 or NaOH. Furthermore, the extent of increases in CBF (54 +/- 2 mL/100 g/min), FS (13 +/- 2%), and LER (-17 +/- 4%) were also markedly attenuated due to the concomitant treatment with amiloride. We conclude that myocardial cellular acidosis plays an important role in mediating coronary vasodilation affected by nisoldipine in the ischemic myocardium. H+ may modulate the property of voltage-dependent Ca channels via Na(+)-H+ exchange.

Further pharmacological study on Sho-seiryu-to as an antiallergic.

Examination was made of the pharmacological characteristics of Sho-seiryu-to, an antiallergic kampo medicine. Sho-seiryu-to suppressed histamine release from rat peritoneal mast cells, but failed to inhibit the binding of [3H]-mepyramine to histamine H1 receptors in guinea pig cerebral cortex and lung. Sho-seiryu-to had no effect on cutaneous reactions induced by serotonin, platelet-activating factor (PAF), leukotriene (LT) C4 or LTD4. Ketotifen prolonged electrically induced convulsions, while Sho-seiryu-to did not. Sho-seiryu-to did not affect salivation induced by pilocarpine. Sho-seiryu-to thus does not appear to inhibit histamine H1 receptors or inflammation induced by serotonin, PAF, LTC4 and LTD4, but suppresses mast cell activity. Sho-seiryu-to would thus have only a few side effects such as dry mouth and convulsions due mainly to the blockage of the action of muscarinic in salivary glands and histamine in the brain.

Protective effects of Acanthopanax senticosus Harms from Hokkaido and its components on gastric ulcer in restrained cold water stressed rats.

The aim of this study is to investigate the pharmacological effect of the stem bark of Acanthopanax senticosus Harms from Hokkaido (Japanese name: Ezoukogi) in place of the root bark as a restorative tonic on the stress-induced gastric ulcer. In the test, the extract of the stem bark of A. senticosus prepared with hot water was dissolved in water and used for the assay of the protective effect of gastric ulcer (erosion) on stressed rats that were restrained on cold water. The result from a single oral administration of the stem bark of A. senticosus-extract (50, 100 and 500 mg/kg, per day) dissolved in 1 ml distilled water did not show any protective effect on gastric ulcer, but the protective effect was observed in a dose-dependent manner from the oral administration of the extract (50, 100 and 500 mg/kg, per day) for 2 weeks. Pre-administration of the stem bark of A. senticosus-extract in a dose of 500 mg/kg showed the most potent inhibition without affecting either body or adrenal glands weights. Among ether, chloroform, n-butanol and aqueous residue extracts from the stem bark of A. senticosus-extract, the n-butanol extract used for oral administration for 2 weeks showed an obvious inhibition of 61.1% on gastric ulcer, compared with the control group which was treated with distilled water in the same way. Chlorogenic acid and syringaresinol di-o-beta-D-glucoside, as the major components of the n-butanol extract, showed a significantly inhibitory effect on gastric ulcer, at 21.4% and 51.3%, respectively. We suggested that the protective effect of the stem bark of A. senticosus on gastric ulcer may be partially due to those of chlorogenic acid and syringaresinol di-o-beta-D-glucoside.

Partial purification and characterization of a protein kinase that is activated by nuclear localization signal peptides.

A nuclear localization signal (NLS) is required for the transport of karyophilic proteins from the cytoplasm to the nucleus. In this study, NLS was examined in terms of its effect on diverse cellular functions such as protein phosphorylation reactions. When synthetic peptides containing the NLS of SV40 T-antigen were injected into the cytoplasm of Xenopus oocytes, and the oocytes incubated with [32P]phosphorous-containing medium, a 32 kDa protein was found to be preferentially phosphorylated in an NLS-dependent manner. The incubation of fractionated cytosolic extracts prepared from mouse Ehrlich ascites tumor cells with [gamma-32P]ATP in the presence of the NLS peptides, results in the stimulation of the phosphorylation of several proteins. Similar in vitro stimulation was observed by other functional NLS peptides such as those of polyoma virus T-antigen and nucleoplasmin. Little or no stimulation, however, was detected for peptides of mutant type and reverse type NLS of SV40 T-antigen, and the C-terminal portion of lamin B. Using an in vitro assay, the phosphorylation activity was fractionated chromatographically and a fraction was obtained which contained a high level of activity. The fraction was found to contain three major proteins having molecular masses of 95, 70, and 43 kDa. The in vivo and in vitro results are consistent with the existence of a protein kinase, called NLS kinase, that is specifically activated by NLS peptides.