GABA receptor agonist promotes reformation of the striatonigral pathway by transplant derived from fetal striatal primordia in the lesioned striatum

Striatal lesions are known to cause the anterograde transneuronal degeneration of the substantia nigra pars reticulata (SNr) neurons in consequence to loss of GABAergic inhibitory striatonigral efferents. The present study was undertaken to examine whether long-term intraventricular administration of the GABA agonist muscimol could promote reformation of the striatonigral pathway arising from transplants by rescuing host SNr neurons from transneuronal death in rats with striatal ischemic lesions. Compared to nongrafted rats with striatal lesions, (i) a prominent axonal projection from the transplants to the ipsilateral substantia nigra, (ii) a significant increase in number of survived neurons in the ipsilateral SNr, and (iii) a significant reduction in number of apomorphine-induced turning behaviors were found in grafted animals with muscimol infusion, but not in those without muscimol administration. These findings suggest that preservation of the host target neurons for grafted cells may increase an efficacy of cerebral implants in establishment of the host-graft fiber connections, possibly, leading to functional restoration.

Bioactive constituents of Chinese natural medicines. IV. Rhodiolae radix. (2).: On the histamine release inhibitors from the underground part of Rhodiola sacra (Prain ex Hamet) S. H. Fu (Crassulaceae): chemical structures of rhodiocyanoside D and sacranosides A and B

The methanolic extract of the underground part of Rhodiola sacra (PRAIN ex HAMET) S. H. Fu was found to show inhibitory activity on the histamine release from rat peritoneal exudate cells induced by an antigen-antibody reaction. From the methanolic extract with the inhibitory activity on histamine release, a new cyanoglycoside called rhodiocyanoside D and two new monoterpene glycosides called sacranosides A and B were isolated, together with eight known compounds, rhodiocyanoside A, heterodendrin, lotaustralin, rhodioloside, 2-phenylethyl alpha-L-arabinopyranosyl(1-->6)-beta-D-glucopyranoside, 2-methyl-3-buten-2-yl beta-D-glucopyranoside, kenposide A, and rhodiooctanoside. The structures of new compounds were determined on the basis of chemical and physicochemical evidence, which included the synthesis of sacranoside A from (-)-myrtenol. All major chemical constituents from R. sacra inhibited the histamine release and, among them, lotaustralin and rhodiooctanoside were found to show potent inhibitory activity.

The modified nucleoside 2-methylthio-N6-isopentenyladenosine in tRNA of Shigella flexneri is required for expression of virulence genes

The virulence of the human pathogen Shigella flexneri is dependent on both chromosome- and large-virulence-plasmid-encoded genes. A kanamycin resistance cassette mutation in the miaA gene (miaA::Km Sma), which encodes the tRNA N6-isopentyladenosine (i6A37) synthetase and is involved in the first step of the synthesis of the modified nucleoside 2-methylthio-N6-isopentenyladenosine (ms2i6A), was transferred to the chromosome of S. flexneri 2a by phage P1 transduction. In the wild-type bacterium, ms2i6A37 is present in position 37 (next to and 3' of the anticodon) in a subset of tRNA species-reading codons starting with U (except tRNA(Ser) species SerI and SerV). The miaA::Km Sma mutant of S. flexneri accordingly lacked ms2i6A37 in its tRNA. In addition, the mutant strains showed reduced expression of the virulence-related genes ipaB, ipaC, ipaD, virG, and virF, accounting for sixfold-reduced contact hemolytic activity and a delayed response in the focus plaque assay. A cloned sequence resulting from PCR amplification of the wild-type Shigella chromosome and exhibiting 99% homology with the nucleotide sequence of the Escherichia coli miaA gene complemented the virulence-associated phenotypes as well as the level of the modified nucleoside ms2i6A in the tRNA of the miaA mutants. In the miaA mutant, the level of the virulence-associated protein VirF was reduced 10-fold compared with the wild type. However, the levels of virF mRNA were identical in the mutant and in the wild type. These findings suggest that a posttranscriptional mechanism influenced by the presence of the modified nucleoside ms2i6A in the tRNA is involved in the expression of the virF gene. The role of the miaA gene in the virulence of other Shigella species and in enteroinvasive E. coli was further generalized.

Posteroventral pallidotomy in a patient with parkinsonism caused by hypoxic encephalopathy

We report a patient with a hypokinetic-rigid form of parkinsonism caused by hypoxic encephalopathy, in whom parkinsonian symptoms were markedly alleviated by staged bilateral posteroventral pallidotomy.

Release of opioid peptides, gluten exorphins by the action of pancreatic elastase

The release of opioid peptides, gluten exorphins A, which have been isolated from the pepsin-thermolysin digest of wheat gluten, with gastrointestinal proteases was examined. High levels of gluten exorphin A5 (Gly-Tyr-Tyr-Pro-Thr) immunoreactive materials were detected in the pepsin-pancreatic elastase digest by a competitive ELISA. From this digest, gluten exorphin A5, B5 and B4 were isolated. This means that these peptides are released in the gastrointestinal tracts after ingestion of wheat gluten. The yield of gluten exorphin A5 in the pepsin-elastase digest was larger than that in the pepsin-thermolysin digest. The gluten exorphin A5 sequence is found 15 times in the primary structure of the high molecular weight glutenin. The region from which gluten exorphin A5 was released by the action of pancreatic elastase was identified using synthetic fragment peptides.

Airway inflammation in COPD assessed by sputum levels of interleukin-8

STUDY OBJECTIVE

To assess the characteristics of airway inflammation in patients with COPD.

METHODS

We measured the sputum concentration of interleukin-8 (IL-8), a chemokine involved in the migration and activation of neutrophils and eosinophils. We also measured myeloperoxidase (MPO) as a parameter of neutrophil activity and eosinophil cationic protein (ECP) as a parameter of eosinophil activity. Spontaneous sputum samples were obtained from 33 patients with stable COPD and 30 patients with asthma. Induced sputum samples were obtained from 12 normal control subjects.

RESULTS

The sputum concentration of IL-8 was significantly higher in the patients with COPD than in the patients with asthma or in the control subjects (p<0.0001). Concentrations of MPO and ECP were significantly higher in the patients with COPD than in the control subjects but did not differ significantly between the patients with COPD and those with asthma. In the patients with COPD, the sputum concentration of IL-8 was significantly correlated with the concentration of MPO (r=0.55, p<0.001) and of ECP (r=0.53, p<0.01). The sputum concentration of IL-8 was negatively correlated with FEV1/FVC (r=-0.78, p<0.0001) in the COPD group.

CONCLUSIONS

Results suggest the activation of both neutrophils and eosinophils in the airways of patients with COPD. It appears that IL-8 plays a primary role in this activation. The sputum concentration of IL-8 appeared to be closely associated with the degree of airflow obstruction in patients with COPD and may serve as a marker in evaluating the severity of airway inflammation, which is a risk factor for COPD.

Medicinal foodstuffs. VII. On the saponin constituents with glucose and alcohol absorption-inhibitory activity from a food garnish "Tonburi", the fruit of Japanese Kochia scoparia (L.) Schrad.: structures of scoparianosides A, B, and C

The methanolic extract of a food garnish "Tonburi", the fruit of Japanese kochia scoparia (L.) Schrad. (Chenopodiaceae), was found to inhibit the increase in serum glucose-loaded rats. Through bioassay-guided separation, momordin Ic and its 2'-O-beta-D-glucopyranoside were isolated as the active principles from this medicinal foodstuff together with three new saponins named scoparianosides A, B, and C. The structures of scoparianosides A, B, and C were elucidated on the basis of chemical and physicochemical evidence as 3 beta, 22 alpha-dihydroxyolean-12en-28-oic acid (22 alpha-hydroxyoleanolic acid), 3-O-beta-D-xylopyranosyl (1 --> 3)-beta-D-glucopyranosiduronic acid, 3 beta-hydroxyolean -18-en-28-oic acid (morolic acid), 3-O-beta-D-xylopyranosyl(1 --> 3)-beta-D -glucopyranosiduronic acid, and 3 beta-hydroxyolean-13(18)-en-28-oic acid, 3-O-beta-D-xylopyranoxyl(1 --> 3) -beta-D-glucopyranosiduronic acid. Momordin Ic and its 2'-O-beta-D-glucopyranoside, both of which are the principal saponin constituents of this medicinal foodstuffs, were found to potently inhibit glucose and ethanol absorption in rats.

Specific Binding of the Syringolide Elicitors to a Soluble Protein Fraction from Soybean Leaves

Syringolides are glycolipid elicitors produced by Gram-negative bacteria expressing Pseudomonas syringae avirulence gene D. The syringolides mediate gene-for-gene complementarity, inducing the hypersensitive response only in soybean plants carrying the Rpg4 disease resistance gene. A site(s) for 125I-syringolide 1 was detected in the soluble protein fraction from soybean leaves, but no evidence for ligand-specific binding to the microsomal fraction was obtained. The Kd value for syringolide 1 binding with the soluble fraction was 8.7 nM, and binding was greatly reduced by prior protease treatment or heating. A native gel assay was also used to demonstrate ligand-specific binding of labeled syringolide 1 with a soluble protein(s). Competition studies with 125I-syringolide 1 and several structural derivatives demonstrated a direct correlation between binding affinity to the soluble fraction and elicitor activity. However, differential competition binding studies disclosed no differences in syringolide binding to soluble fractions from Rpg4/Rpg4 or rpg4/rpg4 soybean leaves. Thus, the observed binding site fulfills several criteria expected of an intracellular receptor for the syringolides, but it is most likely not encoded by the Rpg4 gene. Instead, the Rpg4 gene product may function subsequent to elicitor binding, possibly in intracellular signal transduction.

[An autobacteriographic study on distribution and localization of methicillin-resistant Staphylococcus aureus in the immunosuppressed mice]

Cyclophosphamide (CY, 250 mg/kg) was intraperitoneally administered to mice. Four days after, a rifampicin-resistant strain of methicillin-resistant Staphylococcus aureus (MRSA, S. aureus 1-6 RFPr) was intravenously inoculated at the level of 10(7) cfu/mouse. Distribution and localization of the inoculated organism were chronologically investigated by means of whole body autobacteriography. CY (100 mg/kg) was consecutively administered for 4 days following the inoculation. As a result, dense colonies of the organism were detected from many organs and tissues, that is, the liver spleen, gastrointestinal tract, kidneys, urinary bladder and bone (bone marrow) on the day after the inoculation. Following 3 days after the inoculation, the distribution and localization in CY-treated mice remained substantially unchanged and some animals died. It is demonstrated that in an experimental mouse model of MRSA infectious disease under immunosuppressed condition, the inoculated organism can stand still and proliferate not only in the gastrointestinal tract but also in the urinary tract and lymphhemopoietic organs.

Bioactive saponins and glycosides. X. On the constituents of zizyphi spinosi semen, the seeds of Zizyphus jujuba Mill. var. spinosa Hu (1): structures and histamine release-inhibitory effect of jujubosides A1 and C and acetyljujuboside B

New dammarane-type triterpene oligoglycosides, jujubosides A1 and C and acetyljujuboside B1 were isolated from Zizyphi Spinosi Semen, the seeds of Zizyphus jujuba MILL. var. spinosa Hu, together-with three known saponins. The structures of jujubosides A1 and C and acetyljujuboside B were determined on the basis of chemical and physicochemical evidence. Jujubosides A1 and C and acetyljujuboside B were found to inhibit the histamine release from rat peritoneal exudate cells induced by antigen-antibody-reaction.

[A case of Mycobacterium intracellulare infection associated with sinobronchial syndrome]

The patient was 71-year-old male with a history of sinobronchial syndrome since 8 years ago. He has been suffering from cough, sputum and upper abdominal discomfort since January 1994. He was diagnosed as an early gastric cancer by endoscopy, and his chest X-ray film showed an infiltrative shadow in the right upper lung field. A smear of the sputum specimen was positive for acid fast bacilli, which were later identified as Mycobacterium intracellulare. In this case, before the Mycobacterium intracellulare infection, it was confirmed that his mucociliary transport was severely impaired by using aerosol inhalation cine-scintigraphy. This case suggests that an impairment of the local defence mechanisms may play an important role in the pathogenesis of Mycobacterium intracellulare infection.

[A case of primary pulmonary intimal sarcoma of the pulmonary artery]

We report the pulmonary intimal sarcoma of the pulmonary artery which is encountered infrequently. The patient, a 67-year-old man, was admitted with right heart failure. Diagnosis was not established completely by computed tomography of the thorax, pulmonary angiogram and pulmonary scintigram, therefore chronic pulmonary thromboembolism was suspected. Palliative resection was performed with cardiopulmonary bypass and total circulatory arrest. Pathologic examination of the resected tumor revealed pulmonary intimal sarcoma, which originated from the pulmonary artery. The patient died four months postoperatively. The cause of death was determined by autopsy to be recurrent pulmonary intimal sarcoma invading the left atrium and multiple metastasis of the brain, pancreas, adrenal glands and right lung.

Spiral computed tomography with 3-dimensional reconstruction for the diagnosis of tracheobronchial stenosis

We report on the usefulness of spiral computed tomography (CT) with 3-dimensional (3D) reconstruction in the diagnosis of tracheobronchial abnormalities based on three cases of children with congenital tracheobronchial strictures. Images were reconstructed using a curved planar reformat and shaded surface display. The images obtained from our three cases of tracheal stenosis, subglottic stenosis and tracheobronchial strictures were extremely clear. Spiral CT with 3D reconstruction provides excellent anatomic delineation of the tracheobronchial airway, and is safe and less invasive than tracheobronchography.

Inhibitory mechanisms of oleanolic acid 3-O-monodesmosides on glucose absorption in rats

We examined the action mechanism of oleanolic acid 3-O-monodesmoside, momordin Ic (1), and oleanolic acid 3-O-glucuronide (2) for the inhibitory effect on the increase in serum glucose levels in oral glucose-loaded rats. Although 1 and 2 dose-dependently inhibited the increase in serum glucose levels in oral glucose-loaded rats, these compounds showed no significant effects on serum glucose levels in normal rats, intraperitoneal glucose-loaded rats, and alloxane-induced diabetic mice. Furthermore, 1 and 2 were found to suppress gastric emptying in rats, and also to inhibit the glucose uptake in rat small intestine concentration dependently in vitro. These results indicate that 1 and 2 given orally have neither insulin-like activity nor insulin releasing-activity. 1 and 2 apparently inhibited glucose absorption by suppressing the transfer of glucose from the stomach to the small intestine and by inhibiting the glucose transport system at the small intestinal brush border.

[QRS axis shift in deep breathing]

We examined changes in mean QRS axis of electrocardiogram during the deep breathing test in outpatients with hypertension, ischemic heart disease, and/or diabetes mellitus. The mean age of all patients (n = 596; male 327, female 269) was 63.0 years (male 62.7 years, female 63.4 years). The average of the mean QRS axis in all patients was shifted to the right during deep inspiration. The changes in mean QRS axis during deep breathing test were more than 60 degrees in 27 patients (4%) (mean age: 70.0 years), 30-59 degrees in 118 patients (20%) (mean age: 65.5 years), and 0-29 degrees in 451 patients (76%) (mean age: 61.9 years). These results suggest that the changes in mean QRS axis during deep breathing are greater in the aged patients.

[A case report on mitral valve replacement associated with antiphospholipid syndrome in systemic lupus erythematosus]

Mitral valve replacement (MVR) was performed on a 36-year-old woman for mitral valve regurgitation. The patient suffered from antiphospholipid syndrome (APLS) with systemic lupus erythematosus (SLE). The patient required 4 times plasma exchanges to prevent embolization to the cerebral arteries. A decrease in the anticardiolipin beta 2-glycoprotein I complex level was achieved and MVR was performed with a relatively good postoperative course. Anticoagulation therapy had been continued, but one year postoperatively the patient fell down a staircase and suffered acute epidural hematoma. Emergency operation was performed. The patient, however, died due to cerebral hemorrhage.

[Cytokine producing ability of peripheral blood mononuclear cells in the clinical course of pulmonary tuberculosis]

Interferon-gamma (IFN-gamma) and interleukin-10 (IL-10)-producing ability of peripheral blood plastic-dish adherent cells and non-adherent cells obtained from patients with active pulmonary tuberculosis (N = 17) and healthy controls (N = 14) upon stimulation with purified protein derivatives (PPD) were assessed. Adherent cells and non-adherent cells were obtained two times from each patient with active pulmonary tuberculosis without any underlying diseases, on admission before the initiation of administering anti-tuberculous drugs and 2 months later from the negative conversion of Mycobacterium tuberculosis in sputum culture. ELISA was performed to measure IFN-gamma and IL-10 levels in culture media of adherent cells and non-adherent cells stimulated with PPD. IFN-gamma levels produced by non-adherent cells on admission were significantly higher than that of healthy controls (p < 0.001). Elevated IFN-gamma levels on admission was reduced after treatment for tuberculosis (p < 0.03), but still remained higher than that in healthy controls. IL-10 levels of non-adherent cells of patients were lower than those of healthy controls, although the difference was not significant. IL-10 levels produced by non-adherent cells on admission correlated with the time needed for negative conversion of bacilli in sputum culture (p < 0.05). IL-10 level produced by adherent cells from nutritionally normal patients were significantly higher than that of healthy controls (p < 0.05), and elevated IL-10 level was significantly reduced after therapy (p < 0.05). In the normonourished patients, the time needed for negative conversion of the bacilli in sputum culture of patients kept higher level of IL-10 of non-adherent cells (N = 5) was significantly longer than that of patients reduced IL-10 level after therapy. These results suggest that IL-10 produced by monocytes may diminish the TH1 responses of patients with pulmonary tuberculosis.

Bioactive saponins and glycosides. VIII. Notoginseng (1): new dammarane-type triterpene oligoglycosides, notoginsenosides-A, -B, -C, and -D, from the dried root of Panax notoginseng (Burk.) F.H. Chen

The glycosidic fraction from the dried roots of Panax notoginseng (Burk.) F.H. Chen was found to show protective effect on liver injury induced by D-galactosamine and lipopolysaccharide. From the glycosidic fraction with hepatoprotective effect, nine new dammarane-type triterpene oligoglycosides, notoginsenosides-A, -B, -C, -D, -E, -G, -H, -I, and -J and an acetylenic fatty acid glycoside, notoginsenic acid beta-sophoroside, were isolated together with fourteen known dammarane-type triterpene oligoglycosides. The structures of notoginsenosides-A, -B, -C and -D were determined on the basis of chemical and physicochemical evidence, which included the chemical correlation with ginsenoside-Rb1 using photosensitized oxygenation, as follows: notoginsenoside A; 3-O-[beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl] 3 beta, 12 beta,20(S),25-tetrahydroxydammar -23-ene; B; 3-O-[beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-glucopyranosyl (1-->6)-beta-D- glucopyranosyl] 3 beta, 12 beta,20(S)-trihydroxydammar-25-en-24-one, C; 3-O-[beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D -glucopyranosyl (1-->6)-beta-D-glucopyranosyl] 3 beta,12 beta,20(S)- trihydroxy-24 zeta-hydroperoxydammar-25-ene, and D; 3-O-[beta-D-xylopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-xylopyranosyl (1-->6)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl]20(S)-protopanaxadiol, respectively.

Tissue-specific expression of HSV-tk gene can induce efficient antitumor effect and protective immunity to wild-type hepatocellular carcinoma

The efficacy of expression of the herpes simplex virus thymidine kinase (HSV-tk) gene under the transcriptional control of the liver-specific albumin gene promoter, followed by ganciclovir treatment, was investigated both in vitro and in vivo. Murine and rat hepatocellular carcinoma (HCC) cells infected with retroviruses carrying the HSV-tk gene under the control of the murine albumin gene promoter were selectively killed by ganciclovir treatment in vitro, whereas non-HCC cells, such as murine mammary tumor cells and fibroblast cells, which were infected with the same retroviruses, were not. Susceptibility of the retroviral-infected HCC cells to ganciclovir was more than 100-fold higher than that of the retroviral-infected non-HCC cells. When mice bearing a bulky HCC mass consisting of the retroviral-infected HCC cells were treated with systemic ganciclovir administration, complete regression of the tumors was observed without any signs of overt toxicity. Profound antitumor effects on preestablished murine HCCs were observed when wild-type HCC cells were implanted into animals with a small percentage of the retroviral-infected counterparts. When only 5% of the cells were infected with retroviruses carrying the HSV-tk gene, significant inhibition of tumor development was observed with systemic ganciclovir treatment. Importantly, animals that were treated with implantation of mixtures of the retroviral-infected and parental HCC cells, followed by ganciclovir administration, did not exhibit tumor formation and resisted subsequent rechallenge with wild-type HCC cells. Our results indicate the feasibility of combination therapy with the HSV-tk gene and ganciclovir for the treatment of HCC.

Percutaneous transluminal coronary angioplasty for morphologic left anterior descending artery lesion in a patient with dextrocardia. A case report and literature review

A case report of percutaneous transluminal coronary angioplasty (PTCA) to treat coronary atherosclerotic lesions in a patient with dextrocardia associated with situs inversus totalis is presented. The patient was a sixty-two-year-old man who was admitted with a diagnosis of congestive heart failure. Cardiac catheterization was performed. Left ventriculography showed mild hypokinesis in segments 2 and 3 with ejection fraction of 63%. Coronary arteriography revealed 74% stenosis in segment 7 of the left anterior descending (LAD) artery. PTCA for this lesion was performed. Successful dilation was achieved with the residual stenosis in the LAD reduced from 74% to 34%. Performance of PTCA in patients with dextrocardia is extremely rare, and only 8 cases have been reported to date. However, by visualizing the procedure as a mirror image and choosing a guide catheter that permits good engagement, it appears possible to perform it like ordinary PTCA.

[Exercise performance and body composition in patients with chronic obstructive pulmonary disease]

Malnutritions is one cause of exercise intolerance in patients with chronic obstructive pulmonary disease. We studied the relation between exercise limitation and body composition in 20 clinically stable patients with chronic obstructive pulmonary disease. Maximal work capacity was measured during incremental exercise on a cycle ergometer, along with maximal oxygen uptake. Anaerobic threshold was determined by the V-slope method. Bone mineral content, lean mass, and fat mass were assessed by dual-energy X-ray absorptiometry. Bone mineral content and lean mass were significantly lower in moderately malnourished patients (%IBW < 80) than in well-nourished patients (%IBW > or = 90). Fat mass was significantly lower in mildly malnourished patients than in well-nourished patients. Maximal work capacity, maximal oxygen uptake, and anaerobic threshold correlated significantly with lean mass, but not with fat mass. These data suggest that lean mass is one determinant of exercise capacity in patients with chronic obstructive pulmonary disease.

Studies on Alismatis rhizoma. I. Anti-allergic effects of methanol extract and six terpene components from Alismatis rhizoma (dried rhizome of Alisma orientale)

Methanol and aqueous extracts (TMe-ext and TAq-ext) from dried rhizomes of Alisma orientale have been screened for activity in experimental models of type I-IV allergies. In the type III allergic model, TMe-ext at oral doses of 50, 200 mg/kg showed an inhibitory effect on the direct passive Arthus reaction (DPAR) in rats, while TAq-ext did not. Four triterpenes (alisol A, alisol B, alisol A monoacetate and alisol B monoacetate) and two sesquiterpenes (alismol and alismoxide) isolated from TMe-ext also exhibited this inhibitory effect. In a type I allergic model, TMe-ext inhibited 48-h homologous passive cutaneous anaphylaxis (PCA) in rats. In a type II allergic model, it was found that TMe-ext inhibits reversed cutaneous anaphylaxis (RCA) in rats. Furthermore, in a type IV allergic model, TMe-ext had an inhibitory effect on the induction phase in picryl chloride-induced contact dermatitis (PC-CD) in mice. These results indicate that Alismatis Rhizoma not only inhibits antibody-mediated allergic reactions but also influences cell reactions and should be recognized as a material for the treatment of allergic reactions, and the anti-type III allergic components are partially attributable to the terpenes mentioned above.

Postnatal ontogeny of striatal-enriched protein tyrosine phosphatase (STEP) in rat striatum

The present study was undertaken to examine developmental change in expression of striatal-enriched protein tyrosine phosphatase (STEP) in the postnatal striatum of rats. For this purpose, immunohistochemical staining and transimmunoblotting analyses were carried out using a cDNA-generated polyclonal antibody to the STEP with a molecular weight of 46 kDa. Immunostaining showed that in neonatal striatum STEP-immunoreactivity was found in discrete patches composed of many immature cells, which corresponded to the tyrosine hydroxylase-immunopositive "dopamine islands." With development there was an increase in staining intensity and in the number of positively reacting cells. By 4 weeks postnatally, STEP-immunoreactivity was almost homogeneously distributed throughout the striatum, as was seen at the adult stage. Immunoblotting analysis showed that STEP protein expression abruptly increased from 2 to 4 weeks postnatally when it reached the adult level. These findings suggest that STEP is involved in development and maturation of the striatal neurons.