Purpose: Disuse of muscle results in atrophy and concurrent capillary regression. We have previously shown that exercise preconditioning prevented the disuse atrophy. Here we investigated whether and how exercise preconditioning affects capillary regression in disuse muscle atrophy by clarifying gene expression of angiogenetic factors. Methods: HIF-1α, VEGF, KDR/Flk-1, Flt-1, angiopoietin-1, and Tie-2, and several proteolytic systems were analysed using a real time polymerase chain reaction (PCR) in rat soleus muscle after hindlimb unloading for 2 weeks with and without exercise preconditioning. Results: The capillary density in unloaded soleus muscle with exercise preconditioning was significantly higher than that without exercise. Real time PCR analysis showed lower mRNAs expression levels of angiogenic factors in unloaded muscle without exercise preconditioning than that of control muscles. The exercise preconditioning attenuated the decreases in the expression levels of the angiogenic genes by muscle unloading, especially KDR/Flk-1, Flt-1 and Tie-2. Concluding Remarks: Disuse by hindlimb unloading induced significant reduction of the capillary network with decreases of angiogenic factors. Exercise preconditioning attenuated the capillary regression in hindlimb unloaded soleus muscle by preserving the gene expression levels of these angiogentic factors. [J Physiol Sci. 2007;57 Suppl:S243]

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Most of the stereoisomers of D-glucose are rarely found in the nature. Because of the similarities of the structures, these rare sugars are expected to behave like D-glucose, but in some cases, inhibit or strengthen the effect of D-glucose. Obesity is resulted from an excess storage of fat in adipocytes, and is a worldwide health problem associated with serious complications including a high incidence of hypertension, coronary heart disease and type 2 diabetes. Adipocytes synthesize triacylglycerol (TG) from fatty acids and/or sugars, while secreting many kinds of adipocytokine. To estimate the applicability of rare sugars to anti-obesity drugs, we examined the effects of monosaccharides on the properties of adipocytes. METHODS: 3T3-L1 preadipocytes were purchased and differentiated. Three days after the differentiation, nine kinds of monosaccharides including rare sugars were added to the culture medium. The activity of GPDH (glycerol-3-phosphate dehydrogenase) in cytoplasm, the amount of the accumulated TG, and the concentrations of leptin and adiponectin secreted in the culture medium were measured. CONCLUSIONS: D-glucose increased GPDH activity and TG amount, but showed no effect on leptin and adiponectin concentrations. Rare sugars, D-allose, D-psicose and D-altrose, did not increase GPDH nor TG, but slightly decreased the concentration of leptin and/or adiponectin. [J Physiol Sci. 2007;57 Suppl:S243]

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The modification of the measuring system in small animal isolated papillary muscle. (II)Nishiura,Naoki ; Mori Hidezo. (Nat. Cardio-vascular Ctr. Res. Inst. Department of the Cardiac Physiology Osaka Japan)Last year, we presented the modified traditional measuring system that was employed the pen motor galvanometer to control the force and length of small animal isolated papillary muscles. This year, to reduce the noise and improved the sensitivity, we could employed the speaker (FOSTEX FF125K) instead of the pen-motor. This new modified system configuration is almost same as previous system. However, the substance of the circuit and tools are developed for stable operation or easy treatments. The arm that hold the papillary muscle consists of 2 arms that have been attached the speaker and load cell. Position sensor attached to the arm on the side of the speaker. This sensor is magnetic operation device. The temperature control, one thermo-regulated apparatus (Coolnics circulator CTE22A) control the both tyrode liquid and chamber. Papillary muscle arranged between 2 arms was set in the chamber. At the bottom of this chamber, making the window that attached the cover glass to observe a papillary muscle under the microscope during the experiment. Therefore we could fabricated the new modified apparatus to measure the force and length of small animal papillary muscles. [J Physiol Sci. 2007;57 Suppl:S243]

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JuzenTaihoTo (JTT) is well known to frequently use for the treatment of chronic diseases and anemia with favorable success. Administration of JTT into patients with gastic cancer and liver cancer is also recognized to cause decrease in cancer volume and metastasis. Our previous works clearly showed that JTT could enhance the activity of both NK and NK T cells and results in favorably modification of the clinical onditions of cancer patients. It is well accepted that several types of cytokines such as interferon (IFN)-γ and IL-12 are responsible for the activation of NK and NK T cells.The present study, therefore, was undertaken to examine the influence of JTT on cytokines, which responsible for the inhibition of cancer metastasis by using B16 melanoma/mouse system. C57BL/6 male mice were fed normal mouse chow contained 1% JTT for three weeks.These mice were injected intravenously with 2×10⁵ B16 melanoma cells on 8th of JTT administration. Metastasis of B16 in lung tissues were examined two weeks later.This suppressive activity of JTT on metastasis was abrogated by the pretreatment of mice with Amrinone or anti-IFN-γ antibody. In Amrinone treated group, there are many B16 metastasis in lung compared with anti-IFN-γ antibody treated group.These results strongly suggest that JTT enhances these cytokines and results in inhibition of cancer metastasis in vivo. [J Physiol Sci. 2007;57 Suppl:S243]

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There is much evidence that the reactive oxygen species(ROS) affect several types of diseases. Although bisphosphonates, such as etidronate and alendronate(AR),are frequently used for the treatment of osteoporosis, the influence of bisphosphonate on the production of ROS is not fully understood. The present study, therefore, was designed to examine the influence of bisphosphonate, especially AR, on the production of ROS in vitro and in vivo. The first set of experiments was carried out to examine the in vitro effect of AR on the production of ROS by examining the ability of fibroblasts from rats with adjuvant arthritis to produce nitric oxide in response to lipopolysaccharide(LPS)stimulation.It caused suppression of NO production from fibroblasts and the minimum dose of AR was 10.0ng/ml.The second part of experiments were designed to examine whether the suppressive activity of AR on ROS production in vivo was observed in vitro by measuring hydroperoxide contents in plasma. Thus, adjuvant arthritis in Lewis rats were injected intraperitoneally with various doses of AR once a day for 3 weeks.Daily intraperitoneally with various doses of AR once a day for 3 weeks,starting one week after adjuvant injection. Daily intraperitoneal administration of AR at more than 0.5ng/kg for 3weeks could cause the significant suppression of hydroperoxide formation in plasma. These results may suggest that AR could suppress the production of reactive oxygen species and results in attenuation of the clinical conditions of disease with bone destruction. [J Physiol Sci. 2007;57 Suppl:S244]

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BACKGROUND: The fatty acid composition of horse oil is similar to human sebum and contains a large amount of linoleic acid and α-linolenic acid; therefore, its topical application is expected to improve the skin function and microcirculation. METHOD: To confirm the effectiveness of topical horse oil application, we conducted three kinds of experiments using hairless mice. As a control, we did not apply any ointment. First, we administered percutaneously horse oil, olive oil and petrolatum on the dorsal skin and evaluated transepidermal water loss (TEWL) and hydration during 4 hours. Second, we measured vascular diameters and blood flow velocity by using Dorsal Skinfold Chamber during 4 hours. Third, two small burn injuries were made on the dorsal area. On the right side, we applied horse oil every day for a week, on the left side was used as a control. TEWL and Hydration were evaluated at 0,1,3,5 and 7days. RESULTS: First, the application of horse oil and petrolatum caused significant decrease in TEWL vs. control (p<0.05 and p<0.01, respectively). Second, there was a significant vasodilation of arterioles after 10 minutes of horse oil application (p<0.01). On the other hand, there was vasoconstriction by application of olive oil (p<0.01). Third, horse oil application on burn decreased TEWL vs. control (p<0.01) at 1 day or later. CONCLUSION: Horse oil as a preparation for local external use is suitable to maintain and improve the humidity and microcirculation of the skin. Finally, we consider that horse oil might be also useful for the prevention and treatment of conditions like dry skin and skin ulcer. [J Physiol Sci. 2007;57 Suppl:S244]

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The balance of cervical muscle groups is easily destroyed because the head and cervical vertebrae do not exist en bloc, and are bound by the craniospinal joint through soft tissues. Thus, it is very important to elucidate the activity patterns of muscle groups that connect the head and neck during occlusion and mastication, and the mechanics of the skull and cervical vertebrae induced by activities of these muscle groups. In this study, we investigated the mechanics of the head and neck region during occlusion and mastication using rabbits. A triaxial strain gauge was attached to the occipital squama and bilateral parietal bones under anesthesia. After sufficient masticatory movement was confirmed following arousal from anesthesia, the animals masticated pellets, carrots, and cabbages, and the strain of each bone was measured. As results, it was clarified that the activities of the muscle groups of the occipital bone and 1st cervical vertebra are for maintaining the head at a position easier for mastication, and those of the 2nd cervical vertebra are for dislocation of the head to the masticatory side for efficient mastication, which leads to dislocation and deformation of the bones composing the skull for masticatory efficiency. [J Physiol Sci. 2007;57 Suppl:S244]

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Many lines of evidence indicate that infants prefer infant-directed (ID) speech to adult-directed (AD) speech. ID speech has a unique acoustic signature characterized by a higher fundamental frequency (pitch). However, the individual variation of the pitch is too large to discriminate ID speech and AD speech. So we introduced a statistical modeling method to automatically discriminate ID speech and AD speech without pitch information. Eight mothers and their infants were participated in this study. Each mother read 3 picture-books to her infant and to an adult. As a result, 2,034 sentences/21,304 words were recorded for ID and AD speeches. Twelve dimension mel-frequency cepstral coefficients (MFCC), their derivatives and a log-energy derivative were extracted from them as speech features. Using these features, mono-phone HMMs (hidden Markov models) representing ID and AD speech type were trained. Using these models, we determined whether a mother's speech was classified into ID or AD speech. Log likelihood of unknown speeches was calculated with these models, and ID or AD speech type of the model with maximum log likelihood was chosen as the discrimination result. In speaker open conditions, 80.9% of ID/AD speeches were correctly discriminated. This result implies that features associated with ID speech are included in the MFCC and a stochastic modeling method using HMM with MFCC is capable of ID and AD speech discrimination. [J Physiol Sci. 2007;57 Suppl:S244]

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To investigate the effects of salivation on physical properties of food bolus during mastication, the texture of the bolus and the salivation were measured in adult participants. Twenty healthy adult volunteers (mean age 28.1 yrs) masticated two test foods (B, white bread; S, fish sausage). The food bolus was collected at three different stages of mastication, early stage (E), middle stage (M) and late stage (L, just before swallowing). The texture of the bolus was measured according to the texture profile analysis. The salivary ability in each participant was estimated the volume of saliva while chewing a dental cotton ball for 2 minutes. Hardness of two test food bolus (B and G boluses) decreased during mastication. Adhesiveness of the B bolus had maximum value at the M stage. However, adhesiveness of the S bolus showed the following two characteristics. In ten participants, it increased from the M stage to the L stage (increased group). While, it had a maximum value at the M stage in the other ten participants (decreased group). The mean volume of saliva in the decreased group (5.16 ml) was significantly higher than that in the increased group (2.56 ml). These findings suggest that the volume of salivation may influence the adhesiveness depending on the type of food bolus during mastication. [J Physiol Sci. 2007;57 Suppl:S245]

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The purpose of the present study is to investigate the changes of calcaneal bone mass and leg extension power by muscular strength training and de-training. Subjects were eleven women (aged range 18 to 19 years) with low body mass index (mean BMI=17.4). They participated in our experiments after giving their informed consent. The muscular strength training was performed by leg press, leg extension and leg curl using machines respectively. The process of the experiment consisted of two times control experiments (C1,C2) before training, for a nine weeks training period (T-period) and for a six months de-training period (DeT-period). Calcaneal bone mass, leg extension power and body composition were measured in C1, C2, after T-period and after DeT-period. Relative calcaneal bone mass (%) was calculated by means of standard value of seventeen-aged women bone mass in this study. The mean value of the bone mass of eleven subjects after T-period increased by 6.5% to 88.8% as compared with that of C2 (82.3%). And the value of the bone mass after DeT-period decreased by 5.5% to 83.3% as compared with that after T-period. In the corresponding the change of the bone mass values, the mean value of the leg power extension also changed in C1, C2, after T-period and after DeT-period. However, the correlation between the rate of the change of bone mass and the rate of the change of leg extension power in individual subjects was not observed. It was conjectured that quantity of harder mechanical stress as muscular strength training influences calcaneal bone mass in this study. [J Physiol Sci. 2007;57 Suppl:S245]

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To investigate the effect of hypercapnia on the neural and hemodynamic responses, we measured broad band electrophysiological signals (local field potentials, LFP < 100 Hz; multiunit activity, MUA > 300 Hz), optical intrinsic signals (586 and 605 nm, indicators of CBV and oxygenation), spectral changes in reflected light (400-900 nm) and laser-Doppler blood flow. Rats were anesthetized with alpha-chloralose and artificially ventilated with muscle relaxants. Hypercapnic challenge was performed by 5% and 10% CO₂ inhalation. We recorded these signals while delivering 2-s electrical pulses to the hindpaw. We observed decreases in both neural (LFP, MUA) and hemodynamic (CBF, CBV) responses, and prolonged deoxyhemoglobin increases in the early phase with attenuation of deoxyhemoglobin decreases in the late phase (i.e., disruption of hyperoxygenation responses), compared with those responses during normocapnia. These results suggested that imaging of early dip optical intrinsic signals and positive BOLD fMRI signals might not accurately reflect neural responses in strength and space domains during hypercapnia. [J Physiol Sci. 2007;57 Suppl:S245]

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To study cellular morphology and functions in vivo in realtime, we developed a fiber-coupled confocal microscope (FCM), and observed fluorescently-labeled cells inside the body of anesthetized animal. We developed an imaging fiber bundle (IFB), which consisted of an objective lens and a flexible multi-fiber assembly (unit fiber: NA=0.4, 3.75 micron in diameter). By combining the IFB with Nipkow disk confocal scanner, we detected fluorescent signals of an intracellular molecular messenger in real time (30 frames/sec), and the death processes in the form of fluorescence changes even from cells located deep (2 mm) inside the solid organs. The FCM we developed is very promising for detailed studies in both the cell-based researches and clinical researches. [J Physiol Sci. 2007;57 Suppl:S245]

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Several mutant alleles for ataxic animals have been identified to date and some of them are genetically characterized. Some strains (e.g., pcd) are considered as models for the neuronal degeneration or hereditary spinocerebellar ataxia. We found ataxic Syrian hamsters in our breeding colony, and have maintained them by sibling mating. The hereditary mode of the mutation was autosomal recessive. Homozygotes showed a moderate ataxia beginning at seven to eight weeks of age. They were fertile and showed normal life span. Histological observation revealed that the affected hamsters exhibited an adult-onset degeneration of cerebellar Purkinje neurons, followed by a slow, mild reduction in the density of granule cells. Northern hybridization demonstrated that the expression of Nna1 transcript, the gene responsible for the Purkinje cell degeneration (pcd) phenotype, was almost negligible in the brain of homozygous hamsters. On the other hand, four ataxia-related genes (weaver/Kcnj6, lurcher/Grid2, reeler/Rln, and staggerer/Rora) were expressed comparably in the brain of wild-types and the mutants. These results strongly suggest that pcd-type mutation is involved in the ataxic phenotype of mutant hamsters. Although further studies are necessary to confirm how the mutated allele affects its phenotype, mutant hamsters would be a new tool for the study of neurodegenerative diseases. [J Physiol Sci. 2007;57 Suppl:S246]

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The layers of keratinocytes forms the acid mantle, a fine film with acidic pH (–5.5) on the surface of the skin. In this study, we examined whether the acidic pH affects the membrane currents and intracellular [Ca²⁺]_c in keratinocytes. A proton-activated chloride current (I_{Cl, pH}), was observed by acidic extracellular conditions (pH < 5.5). The current-voltage relation of I_{Cl, pH} showed outwardly rectification. On step-like depolarization, I_{Cl, pH} showed a time-dependent activation. The anion channel blocker 4,4′-diisothiocyanostilbene-2,2′-disulphonic acid (DIDS) rapidly and potently inhibited I_{Cl, pH}, while the niflumic acid shows less effect. The threshold pH for activating I_{Cl, pH} became higher by raising temperature from 25°C to 35°C. The intracellular pH, measured with the BCECF-fluorescence was decreased by lowering the extracellular pH, which was, however, much slower than the appearance of I_{Cl, pH}. Interestingly, the acidic condition (pH 5.0–5.5) induced a sharp increase in the intracellular [Ca²⁺] (Δ[Ca²⁺]_acid) of HaCaT cells. The Δ[Ca²⁺]_acid was store-dependent and was blocked by PLC inhibitor, U73122. In primary human keratinocytes, 5 out of 28 tested cells showed similar Δ[Ca²⁺]_acid while in the other cells, the [Ca²⁺]_i was decreased by acidic pH. In summary, we found the expression of proton-activated Cl⁻ current and external pH-dependent release of intracellular Ca²⁺ store in human keratinocytes. The role of I _{Cl, pH} and its molecular nature require further investigation. [J Physiol Sci. 2007;57 Suppl:S246]

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Mouse B cells express a phosphatidylinositol 4,5-bisphosphate (PIP₂)-inhibited large conductance background K channels (LK_bg). In inside-out membrane patches, the application of ATP inhibited LK_bg due to the generation of PIP₂ by PI-kinases. Generation of arachidonic acid (AA) by phospholipase A₂ is involved in the apoptosis of immature B cells. The application of AA activated BK_bg of B lymphocytes in c-a as well as in i-o patches. The facilitating effects of fatty acids became weaker as the acyl chain is more saturated; AA > oleic acid > plamitic acid. When the activity of BK_bg was inhibited by a direct application of PIP₂ (5 μM), the addition of AA hardly recovered BK_bg activity. The facilitation of BK_bg by AA was fully reversible and unaffected by the treatment with inhibitors of various metabolizing enzymes for AA. Consistent with the activation of BK_bg, the application of AA induced strong hyperpolarization of membrane potential in WEHI-231 cells. The intracellular [Ca²⁺] of WEHI-231 was slowly increased by AA, which was partly diminished by KCl-induced membrane depolarization. Besides the increase of BK_bg, AA activated Ca²⁺ permeable nonselective cation channels. In spite of this effect, AA by itself showed a partial inhibitory effect on store-operated Ca²⁺ entry in WEHI-231. Since the expression of PLA₂ is reportedly higher in immature than mature B lymphocytes, the increased driving force for Ca²⁺ influx by AA might play a crucial role in the regulation and development of B lymphocytes. [J Physiol Sci. 2007;57 Suppl:S246]

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An optimal airway surface liquid is crucial for the mucociliary clearance of lung. In this study, we investigated the effects of sevoflurane on the electrogenic chloride secretion of mouse tracheal epithelium and relevant ion channels. The equivalent short circuit current (I_sc′) of mouse tracheal epithelium was measured in a flow-type Ussing chamber study. After inhibiting the background Na⁺ absorption by luminal application of amiloride, the cAMP-dependent Cl^– secretion was evoked by basolateral application of forskolin and isobutylmethylxanthine (Fsk/IBMX). The Fsk/IBMX induced sustained I_sc′, which was suppressed by basolateral addition of chromanol 293B, a blocker of KCNQ1 K⁺ channel. Also, the application of sevoflurane suppressed the Fsk/IBMX-induced I_sc′ in a dose-dependent manner. To elucidate the relevant ion channels targeted by sevoflurane, a whole-cell patch clamp was performed with COS7 and HEK293 cells expressing CFTR and KCNQ1 channels, respectively. In KCNQ1-expressing cells, the outward current at 80 mV was reduced to 59 ± 4.9% by 3% sevoflurane. However, the CFTR current was not affected by sevoflurane up to 5% of partial pressure. From this study, it is concluded that the inhibition of KCNQ1 underlies the sevoflurane-induced decrease of airway secretion. [J Physiol Sci. 2007;57 Suppl:S246]

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