Effect of Goreisan, a Traditional Japanese Medicine, on Rat Hindlimb Lymphedema.

Secondary lymphedema occurs after cancer surgery involving lymph node dissection owing to the lymphatic system dysfunction. However, the pathophysiology of lymphedema and the molecular pathways involved remain unknown. This study aimed to develop a rat hindlimb lymphedema model and investigate the mechanisms that drive pathophysiology and the effects of the traditional Japanese medicine goreisan on lymphedema. The rat lymphedema model was induced by combination surgeries of popliteal lymph node dissection, skin cautery incision, and fascial ablation coagulation in the right hindlimb using male Wistar rats. The foot volume was significantly increased, and recovery was delayed by combination surgeries. Dermal thickness and dilated lymphatic vessels of the hindlimb were observed on postoperative day 2. The number of infiltrating leukocytes (CD45+ cells), including CD4+ T-cells, increased in the lymphedema group compared with that in the sham group. The relative mRNA expression and protein levels of interleukin-6 (IL-6), CC chemokine ligand 2 (CCL2), transforming growth factor ß1 (TGF-ß1), and Fms-related receptor tyrosine kinase 4 (FLT4) were significantly higher in the lymphedema group than in the sham group. Foot volume was decreased by goreisan, furosemide, and prednisolone treatments. Goreisan diminished the increase in CD4+ T-cells, and the same trend was observed for CCL2 and FLT4 expression. In conclusion, the rat hindlimb lymphedema model in this study exhibited increased foot volume, skin-infiltrating cells, and pathological changes accompanied by inflammatory and fibrotic responses, suggesting that the model presented significant clinical features of lymphedema. Goreisan may exert a therapeutic effect on lymphedema by inhibiting CD4+ T-cell infiltration.

Yokukansankachimpihange, a traditional Japanese (Kampo) medicine, enhances the adaptation to circadian rhythm disruption by increasing endogenous melatonin levels.

The traditional Japanese (Kampo) medicines yokukansan (YKS) and yokukansankachimpihange (YKSCH) have similar formulas and the same indications. In animals or cultured cells, the neuropharmacological actions of YKS are sometimes more beneficial than those of YKSCH. Since both drugs are used to treat sleep disorders in Japan, we examined the ameliorative effects of YKS and YKSCH on circadian rhythm disturbance and compared their efficacy using a mouse model of circadian rhythm disruption. Ramelteon was used as the positive control. Ramelteon treatment significantly reversed decreased running wheel activity during the advanced dark phase, indicating facilitation of circadian adaptation. YKS treatment also reversed the activity in the early period of drug treatment; however, it was not statistically significant. YKSCH treatment significantly reversed the decreased activity during the advanced dark phase. Plasma melatonin (MT) levels were significantly increased in the YKSCH but not in the YKS group. The ameliorative effect of YKSCH on rhythm disruption was significantly inhibited by coadministration of the MT2 receptor antagonist. Therefore, the therapeutic effect of YKSCH on circadian rhythm disruption would be attributable, to elevated endogenous MT levels. Taken together, YKS and YKSCH have different pharmacological properties and may be more precisely prescribed depending on patients' psychological symptoms.

Yokukansan, a Traditional Japanese Medicine, Enhances the L-DOPA-Induced Rotational Response in 6-Hydroxydopamine-Lesioned Rats: Possible Inhibition of COMT.

The aim of the present study was to investigate the effects of the traditional Japanese medicine yokukansan (YKS) on the function of dopamine (DA) in the rat nigrostriatal system. Unilateral 6-hydroxydopamine lesions were produced in the rat nigrostriatal system. Despite a marked loss in the striatal immunoreactivity of tyrosine hydroxylase on the lesion side, striatal serotonin (5-HT) immunoreactivity was not affected. Treatment using L-3,4-dihydroxyphenylalanine (L-DOPA) in conjunction with benserazide for 15 d induced abnormal involuntary movements (AIMs) such as locomotive (rotational response), axial, forelimb, and orolingual movements in the lesioned rats. The L-DOPA-induced locomotive and axial, but not forelimb and orolingual, AIMs were significantly increased and prolonged by the pre-administration of YKS. We next investigated the effects of YKS on the production of DA from L-DOPA in 5-HT synthetic RIN 14B cells. RIN 14B cells produced DA and its metabolite, 3-methoxytyramine (3-MT), following L-DOPA treatment. YKS significantly augmented DA production and inhibited its metabolism to 3-MT in a manner similar to the catechol-O-methyltransferase (COMT) inhibitor entacapone. YKS and some alkaloids (corynoxeine: CX, geissoschizine methyl ether: GM) in Uncaria hook, a constituent herb of YKS, also inhibited COMT activity, indicating that the augmenting effect of YKS on L-DOPA-induced DA production in 5-HT synthetic cells was due to the inhibition of COMT by CX and GM. Our results suggest that YKS facilitates the DA supplemental effect of L-DOPA, and that COMT inhibition by CX and GM contributes, at least in part, to the effects of YKS.

Hydroxy-α sanshool induces colonic motor activity in rat proximal colon: a possible involvement of KCNK9.

Various colonic motor activities are thought to mediate propulsion and mixing/absorption of colonic content. The Japanese traditional medicine daikenchuto (TU-100), which is widely used for postoperative ileus in Japan, accelerates colonic emptying in healthy humans. Hydroxy-α sanshool (HAS), a readily absorbable active ingredient of TU-100 and a KCNK3/KCNK9/KCNK18 blocker as well as TRPV1/TRPA1 agonist, has been investigated for its effects on colonic motility. Motility was evaluated by intraluminal pressure and video imaging of rat proximal colons in an organ bath. Distribution of KCNKs was investigated by RT-PCR, in situ hybridization, and immunohistochemistry. Current and membrane potential were evaluated with use of recombinant KCNK3- or KCNK9-expressing Xenopus oocytes and Chinese hamster ovary cells. Defecation frequency in rats was measured. HAS dose dependently induced strong propulsive "squeezing" motility, presumably as long-distance contraction (LDC). TRPV1/TRPA1 agonists induced different motility patterns. The effect of HAS was unaltered by TRPV1/TRPA1 antagonists and desensitization. Lidocaine (a nonselective KCNK blocker) and hydroxy-ß sanshool (a geometrical isomer of HAS and KCNK3 blocker) also induced colonic motility as a rhythmic propagating ripple (RPR) and a LDC-like motion, respectively. HAS-induced "LDC," but not lidocaine-induced "RPR," was abrogated by a neuroleptic agent tetrodotoxin. KCNK3 and KCNK9 were located mainly in longitudinal smooth muscle cells and in neural cells in the myenteric plexus, respectively. Administration of HAS or TU-100 increased defecation frequency in normal and laparotomy rats. HAS may evoke strong LDC possibly via blockage of the neural KCNK9 channel in the colonic myenteric plexus.

Effects of geissoschizine methyl ether, an indole alkaloid in Uncaria hook, a constituent of yokukansan, on human recombinant serotonin 7 receptor.

Effects of seven alkaloids, geissoschizine methyl ether (GM), hirsutine, hirsuteine, rhynchophylline, isorhynchophylline, corynoxeine and isocorynoxeine, in Uncaria hook, a constituent of the kampo medicine yokukansan, on serotonin(7) (5-HT(7)) receptor were investigated using Chinese hamster ovary (CHO) cell membranes and human embryonic kidney 293 (HEK293) cells stably expressing the human recombinant 5-HT(7) receptor. A competitive binding assay using CHO membranes showed that GM (IC(50) = 0.034 µM) more strongly inhibited the binding of the radioligand [(3)H] LSD to 5-HT(7) receptor than the other alkaloids, suggesting that GM is bound to 5-HT(7) receptor. Agonistic/antagonistic effects of GM (1-50 µM) on the receptor were evaluated by measuring intracellular cAMP levels in HEK239 cells. GM (IC(50) = 6.0 µM) inhibited 5-HT-induced cAMP production in a concentration-dependent manner, as well as the specific 5-HT(7) receptor antagonist SB-269970 (0.1-1 µM). However, GM did not induce intracellular cAMP production as 5-HT did. These results suggest that GM has an antagonistic effect on 5-HT(7) receptor.

The blood-brain barrier permeability of 18ß-glycyrrhetinic acid, a major metabolite of glycyrrhizin in Glycyrrhiza root, a constituent of the traditional Japanese medicine yokukansan.

18ß-Glycyrrhetinic acid (GA) is a major metabolite of glycyrrhizin (GL), which is one of the components of glycyrrhiza root, a constituent herb of the traditional Japanese medicine yokukansan. It is well known that most GL is metabolized to GA in the intestine by bacteria. A previous in vitro study using cultured rat cortical astrocytes suggested that GA activates glutamate transport, which is a putative mechanism of the psychotropic effect of yokukansan. To activate the glutamate transport in the brain, GA must be absorbed into the blood after oral administration of yokukansan and then cross the blood-brain barrier (BBB) to reach the brain. However, there is no data on the BBB permeability of GA derived from yokukansan. In the present study, the BBB permeability of GA was investigated in both in vivo and in vitro studies. In the in vivo study, GA was detected in the plasma, brain, and cerebrospinal fluid of rats orally administered yokukansan. In the in vitro study using a BBB model composed of co-culture of endothelial cells, pericytes, and astrocytes, the permeability rate and apparent permeability coefficient of GA were found to be 13.3 ± 0.5 % and 16.5 ± 0.7 × 10(-6) cm/s. These in vivo and in vitro results suggest that GL in orally administered yokukansan is absorbed into the blood as GA, and then reaches the brain through the BBB. This evidence further supports the possibility that GA is an active component in the psychotropic effect of yokukansan.

The blood-brain barrier permeability of geissoschizine methyl ether in Uncaria hook, a galenical constituent of the traditional Japanese medicine yokukansan.

Geissoschizine methyl ether (GM) in Uncaria hook, a galenical constituent of yokukansan is thought to be one of active components in the psychotropic effect of yokukansan, a traditional Japanese medicine (kampo medicine). However, there is no data on the blood-brain barrier (BBB) permeability of Uncaria hook-derived alkaloids containing GM. In this study, we investigated the BBB permeability of seven Uncaria hook alkaloids (GM, isocorynoxeine, isorhynchophylline, hirsuteine, hirsutine, rhynchophylline, and corynoxeine) using in vivo and in vitro methods. In the in vivo experiment, seven alkaloids in the plasma and brain of rats orally administered with yokukansan were measured by liquid chromatography-mass spectroscopy/mass spectrometric multiple reaction monitoring assay. In the in vitro experiment, the BBB permeability of seven alkaloids were examined using the BBB model composed of co-culture of endothelial cells, pericytes, and astrocytes. In the in vivo study, six components containing GM but not isocorynoxeine were detected in the plasma, and three (GM, hirsuteine, and corynoxeine) of components were detected in the brain. The in vitro BBB permeability data indicated that seven alkaloids were able to cross brain endothelial cells in culture conditions and that the BBB permeability of GM was higher than those of the other six alkaloids. These results suggest that target ingredient GM in yokukansan administered orally is absorbed into the blood and then reaches the brain through the BBB. This evidence further supports the possibility that GM is an active component in the psychotropic effect of yokukansan.

Possible involvement of the transient receptor potential vanilloid type 1 channel in postoperative adhesive obstruction and its prevention by a kampo (traditional Japanese) medicine, daikenchuto.

This study focused on the localization of transient receptor potential vanilloid type 1 (TRPV1) in the intestines in postoperative adhesion model rats and investigated the underlying mechanism for the anti-adhesion action of daikenchuto (DKT), especially in relation to TRPV1. Postoperative intestinal adhesion was induced by sprinkling talc in the small intestine. The expression of TRPV1 mRNA was examined by in situ hybridization and real-time RT-PCR. The effects of DKT and its major ingredient, hydroxy sanshool, with or without ruthenium red, a TRP-channel antagonist, on talc-induced intestinal adhesions were evaluated. The level of TRPV1 mRNA was higher in the adhesion regions of talc-treated rats than in normal small intestine of sham-operated rats. Localization of TRPV1 mRNA expression was identified in the submucosal plexus of both sham-operated and talc-treated rats; and in talc-treated rats, it was observed also in the myenteric plexus and regions of adhesion. Capsaicin, DKT, and hydroxy sanshool significantly prevented formation of intestinal adhesions. The effects of DKT and hydroxy sanshool were abrogated by subcutaneous injection of ruthenium red. These results suggest that pharmacological modulation of TRPV1 might be a possible therapeutic option in postoperative intestinal adhesion, which might be relevant to the prevention of postoperative adhesive obstruction by DKT.

Effects of yokukansan and donepezil on learning disturbance and aggressiveness induced by intracerebroventricular injection of amyloid ß protein in mice.

The effects of yokukansan and donepezil on learning disturbance and aggressiveness were examined in amyloid ß protein (Aß)-injected mice. Intellicage tests showed that both yokukansan and donepezil ameliorated Aß-induced learning disturbance, but the ameliorating effect of donepezil was not enhanced by concomitant administration of yokukansan. On the other hand, a social interaction test showed that Aß-induced aggressiveness was ameliorated by yokukansan, but not by donepezil. Co-administration of both drugs also ameliorated aggressiveness, as did yokukansan alone. In vitro binding assays revealed that yokukansan did not bind to choline receptors or transporters. In vitro enzyme assays revealed that yokukansan did not affect choline acetyltransferase activity or inhibit acetylcholinesterase activity, as did donepezil. These results suggest that yokukansan might ameliorate aggressiveness without interfering with the pharmacological efficacy (antidementia effect) of donepezil and also that concomitant administration of yokukansan might be useful for amelioration of aggressiveness, which was not lessened by donepezil. The difference in the efficacies of both drugs may be due to a difference in their pharmacological mechanisms.

Electron-microscopic examination of effects of yokukansan, a traditional Japanese medicine, on degeneration of cerebral cells in thiamine-deficient rats.

We previously demonstrated that yokukansan ameliorated not only learning disturbance but also behavioral and psychological symptoms of dementia-like behaviors (anxiety, aggressiveness) and neurological symptoms (opisthotonus) induced in rats by dietary thiamine deficiency (TD). In the present study, the effects of yokukansan on degeneration of cerebral cells were further examined electron-microscopically during pre-symptomatic and symptomatic stages in TD rats. In the pre-symptomatic TD stage, which appeared as increase in aggressive behaviors on the 21st and 28th days of TD diet-feeding, severe edematous degeneration of astrocytes was detected by electron microscopy, although the changes were not observed by light microscopy. In the symptomatic TD stage (the 34th day) characterized by development of neurological symptoms, severe sponge-like degeneration and multiple hemorrhages in the parenchyma were obvious by light microscopy. The electron-microscopic examination showed degeneration in neurons, oligodendroglias, and myelin sheaths in addition to astrocytes. TD rats, which exhibited multiple hemorrhages light microscopically, showed severe edematous changes and hypertrophy of the foot processes of astrocytes surrounding blood vessels. Administration of yokukansan ameliorated not only the TD-induced aggressive behavior and neurological symptoms but also degeneration of the cerebral cells. These results suggest that the inhibitory effect of yokukansan on degeneration in various brain cells might be closely related to the amelioration of aggression and neurological symptoms in TD rats.

[Two cases of bilateral upper extremity pareses during laparoscopic colectomy].

We herein report on two cases of bilateral upper extremity pareses developing after laparoscopic colectomy. The first case is a 42-year-old man undergoing laparoscopic colectomy under general and epidural anesthesia. During the operation, he was in a combined lithotomy and Trendelenburg position with his arms abducted to 80 degrees and flexed slightly on padded armboards. Postoperatively, he complained of numbness of bilateral forearms. A diagnosis of hypoperfusion caused by arm band was made. His symptoms subsided in three days by physical training. The second case is a 36-year-old woman who developed injury in the brachial plexus after laparoscopic colectomy. We suspect that the nerve injury was caused by the overstretching of her neck with her head under general anesthesia in Trendelenburg position.

Increase of Akkermansia muciniphila by a Diet Containing Japanese Traditional Medicine Bofutsushosan in a Mouse Model of Non-Alcoholic Fatty Liver Disease.

Non-alcoholic fatty liver disease (NAFLD) is considered a worldwide healthcare problem that mirrors the increased prevalence of obesity. Gut microbiota plays a crucial role in the progression and treatment of NAFLD. Bofutsushosan (BTS), a pharmaceutical-grade Japanese traditional medicine, has long been prescribed in Japan for obesity and obesity-related syndrome. Although BTS has been reported to exert an anti-obesity effect in obese patients as well as various obesity-model animals, its effect on gut microbiota is unknown. Here, the effects of BTS on obesity, liver damage, and the gut microbiome in genetically obese mice, ob/ob, were studied. Seven-week-old ob/ob mice were fed a standard diet with (BTS group) or without (CONT group) 5% BTS for 4 weeks. By comparison to the CONT group, the BTS group showed reduced body weight gain and hyperlipidemia as well as improved liver function. Moreover, gut microbiota in the CONT and BTS group formed a significantly different cluster. Specifically, the genera Akkermansia, Bacteroides and an unknown genus of the family Enterobacteriaceae expanded dramatically in the BTS group. Noteworthy, the population of Akkermansia muciniphila, which is reported to elicit an anti-obesity effect and improve various metabolic abnormalities, was markedly increased (93-fold) compared with the CONT group. These results imply that BTS may be a promising agent for treating NAFLD.

Effects of yokukansan, a traditional Japanese medicine, on memory disturbance and behavioral and psychological symptoms of dementia in thiamine-deficient rats.

Effects of yokukansan (TJ-54) on memory disturbance and behavioral and psychological symptoms of dementia (BPSD) were investigated in thiamine-deficient (TD) rats which were produced by feeding a TD diet for 37 d. Daily oral administration of TJ-54 (0.5, 1.0 g/kg) ameliorated the memory disturbance, anxiety-like behavior, the increase in aggressive behaviors, the decrease in social behaviors, and several neurological symptoms including opisthotonus observed in TD rats, in a dose-dependent manner. In addition, histopathological examinations showed that TJ-54 inhibited the degeneration of neuronal and astroglial cells in the brain stem, hippocampus and cortex in TD rats. Microdialysis experiments showed that TJ-54 inhibited extracellular glutamate rise in the ventral posterior medial thalamus in TD rats. These results suggest that TJ-54 possesses the preventive or progress inhibitive effect against the development of memory disturbance and BPSD-like behaviors induced by the degeneration of neuronal and astroglial cells resulting from TD. TJ-54 may inhibit glutamate-mediated excitotoxicity as one of mechanisms.

Magnified endoscopic observation using narrow-band imaging of periampullary adenoma in a patient with familial adenomatous polyposis.

BACKGROUND: Adenoma of the major papilla carries a relatively high risk of malignant transformation to carcinoma, the leading cause of death in patients with familiar adenomatous polyposis (FAP) after colectomy. CASE REPORT: A 35-year-old man had undergone prophylactic colectomy for FAP 3 years earlier. On the forward-viewing and side-viewing endoscopy done for surveillance, the overlying mucosa of the major papilla showed even granularity. On magnifying duodenoscopy using a narrow-band system (NBI), which uses modified optical filters and yields clear images of fine surface structures on the mucosal layer, a compact formation of round pits was seen in the affected ampulla. The microvascular architecture on NBI magnification showed no abnormalities, such as dilated, tortuous or network-like vessels, suggestive of malignancy. On endoscopic retrograde pancreaticocholangiography there was no intraductal growth, and endoscopic ultrasonography showed confinement to the mucosal layer. The ampullary lesion was completely resected using endoscopic snare papillectomy. Histopathological examination of the removed specimen showed tubular adenoma without malignant foci. The patient's post-treatment course was uneventful and without complications, and no local recurrence was noted on repeat endoscopy. CONCLUSIONS: Thus, endoscopic surveillance and removal of ampullary adenomas appear to be justified.

Influence of aging on the behavioral phenotypes of C57BL/6J mice after social defeat.

Depression and anxiety are common psychiatric disorders that can occur throughout an individual's lifetime. Numerous pathways underlying the onset of these diseases have been identified in rodents using a social defeat stress protocol, whereby socially defeated individuals exhibit depression- and/or anxiety-like phenotypes that typically manifest as social avoidance behavior. However, most studies in this field have been conducted using young adult mice; therefore, information about social defeat stress-related behavioral phenotypes in older mice is limited. In this study, we exposed groups of young adult (8-16 weeks old) and aged (24 months old) C57BL/6J mice to mild social defeat stress by challenging them with aggressive CD1 mice while restricting the intensity of aggression to protect the animals from severe injuries. We then identified stress-induced behavioral changes and compared their expression between the age groups and with a non-defeated (non-stressed) control group. We found that the stressed mice in both age groups exhibited similar reduced social interactions that were indicative of increased social avoidance behavior. Moreover, unlike the young stressed and control groups, only the aged stressed group showed a reduced preference for sucrose, which was correlated with social avoidance behavior. Also, the aged stressed mice exhibited an attenuated defeat-induced increase in water intake. These findings reveal that aging alters behavioral phenotypes after social defeat and that the hedonic behavior of aged mice is more vulnerable to social defeat compared with younger mice.

Importance of the interferon-alpha system in murine large intestine indicated by microarray analysis of commensal bacteria-induced immunological changes.

BACKGROUND: Although microbiota play a critical role in the normal development and function of host immune systems, the underlying mechanisms, especially those involved in the large intestine (LI), remain unknown. In the present study, we performed transcriptome analysis of the LI of germ-free (GF) and specific pathogen-free (SPF) mice of the IQI strain, an inbred strain established from ICR mice. RESULTS: GeneChip analysis, quantitative real-time RT-PCR, and reconfirmation using bacteria-inoculated GF mice revealed differences in the expression levels of several immune-related genes, such as cryptdin-related sequences (CRS), certain subsets of type 1 interferon (IFN)-related genes, class Ib MHC molecules, and certain complements. LI expressed no authentic cryptdins but predominantly expressed CRS2, 4, and 7. The mRNA levels of IFN-related genes, including Irf7, Isgf3g, Ifit1 and Stat1, were lower in SPF- and flora-reconstituted mice. When an oral IFN-alpha inducer tilorone analog, R11567DA, was administered to SPF mice, IFN-alpha was induced rapidly in the LI at 4 h, whereas no IFN-alpha protein was detected in the small intestine (SI) or blood. In situ hybridization and immunohistochemistry suggested that the IFN-alpha production originated from Paneth cells in the SI, and portions of lamina proprial CD11b- or mPDCA1-positive cells in the LI. CONCLUSION: The present study suggests that microbial colonization, while inducing the expression of anti-microbial peptides, results in the down-regulation of certain genes responsible for immune responses, especially for type I IFN synthesis. This may reflect the adaptation process of the immune system in the LI to prevent excessive inflammation with respect to continuous microbial exposure. Further, the repertoire of anti-microbial peptides and the extraordinary role of interferon producing cells in the LI have been found to be distinct from those in the SI.

Down-regulation of a hepatic transporter multidrug resistance-associated protein 2 is involved in alteration of pharmacokinetics of glycyrrhizin and its metabolites in a rat model of chronic liver injury.

Glycyrrhizin (GL) has been used to treat chronic hepatitis in Japan and Europe. It is thought to induce pseudoaldosteronism via inhibition of type 2 11beta-hydroxysteroid dehydrogenase (11beta-HSD2) by glycyrrhetinic acid (GA), a major metabolite of GL. A previous clinical study suggested that 3-monoglucuronyl-glycyrrhetinic acid (3MGA), another metabolite of GL, might play a more important role in the pathogenesis of pseudoaldosteronism. The present study evaluates the pharmacokinetics of GL and its metabolites in rats with chronic liver injury induced by a choline-deficient l-amino acid-defined (CDAA) diet to clarify the relationship between 3MGA and pseudoaldosteronism. In rats fed a CDAA diet, plasma concentrations and urinary eliminations of GL and 3MGA were markedly higher than in the rats fed the control diet; the plasma concentration of GA was unaffected when GL was orally administered. Immunohistochemical analysis revealed the suppression of levels of multidrug resistance-associated protein (Mrp) 2 and its localization in the hepatic tissue of rats fed a CDAA diet. When 3MGA was i.v. injected in rats fed a CDAA diet or injected in Mrp2-dysfunctional Eisai hyperbilirubinemic rats, plasma concentrations of 3MGA were higher, and biliary excretion of 3MGA was lower than in each control group. The results suggested that 3MGA would be excreted to bile via hepatic Mrp2 and that its dysfunction would reduce 3MGA clearance. 3MGA accumulated by liver fibrosis resulted in the increased excretion through renal tubule and might be strongly related to the pathogenesis of pseudoaldosteronism because 11beta-HSD2 is expressed in renal tubular epithelial cells.

Histamine induces nasal obstruction via calcitonin gene-related peptide in sensitized guinea pigs.

The purpose of this study was to characterize the late phase nasal obstruction that is induced by a nasal histamine challenge in sensitized guinea pigs. The volume of the nasal cavity was measured using an acoustic rhinometer. A nasal histamine challenge to unsensitized animals induced nasal obstruction at 30 minutes after the challenge while a challenge to sensitized animals induced nasal obstruction not only at 30 minutes but also at 4-6 hours. Histamine (measured by high-performance liquid chromatography), cysteinyl leukotriene (enzyme-linked immunosorbent assay (ELISA)), prostaglandin D2 (ELISA), eosinophils and basophilic cells of sensitized guinea pigs were not changed in the late phase after histamine challenge. Administration of pyrilamine, a histamine H1 receptor antagonist, and calcitonin gene-related peptide (CGRP) (8-37), a CGRP-1 receptor antagonist, significantly improved histamine-induced nasal obstruction at 30 minutes and in the late phase, respectively. These results suggest that a nasal histamine challenge induces nasal obstruction not only immediately through the histamine H1 receptors but also in a late phase via CGRP.

[Current status of portable disposable infusers].

Portable disposable infusers are widely used for treatment of various types of pain including postoperative pain and cancer pain, because they are simple to use, of lightweight, and inexpensive. In Japan, nine series of infusers are available from eight manufacturers. Volumes and flow rates of various infusers used for pain therapy widely vary from 40 to 500 ml and from 0.5 to 15 ml x hr(-1), respectively. Several infusers have flow selectors and/or patient-controlled analgesia circuits. Such a wide variety enables us to select optimal infusers for individual patients and thus to offer adequate pain control to those patients suffering from severe pain.

Diabetic complications in a new animal model (TSOD mouse) of spontaneous NIDDM with obesity.

The TSOD mouse has been established as an inbred strain with spontaneous development of diabetes mellitus as the first clinical signs of diabetes. Polydipsia and polyuria are observed at about 2 months old only in male mice, after which hyperglycemia and hyperinsulinemia are detected. Following these symptoms obesity gradually develops until about 12 months old. In histopathological examination of the pancreas, severe hypertrophy of pancreatic islets was observed due to proliferation and swelling of B cells. In the kidney, thickening of the basement membrane in glomeruli and an increase of the mesangial area were observed at 18 months old. Motor neuropathy in TSOD mice began to appear at 14 months old and most male mice at 17 months old showed weakness of front and hind paws caused by neuron degeneration in the peripheral nerve. In sensory neuropathy, the threshold in the tail pressure test decreased significantly at 12 months old. Light microscopic and electron microscopic examination of sciatic nerves showed a decrease in the density of nerve fibers by the endoneural fibrosis and loss of these fibers. Degenerative changes of myelinated fibers, separation of myelin sheaths with intralamellar edema and remyelination were frequently observed. In the severely affected nerve fibers, the lamellar structure was completely destroyed and macrophages migrated around the myelin sheath or invaded the intramyelin space. Considering these findings similar to non-insulin dependent diabetes mellitus (NIDDM) in humans, the TSOD mouse should be a useful model for the pathogenic study of diabetic complications, especially of peripheral neuropathy.