Nanopore sequencing in distinguishing between wild-type and vaccine strains of Varicella-Zoster virus

BACKGROUND

The introduction of varicella vaccines into routine pediatric immunization programs has led to a considerable reduction in varicella incidence. However, there have been reports of varicella, herpes zoster, and meningitis caused by the vaccine strain of varicella-zoster virus (VZV), raising concerns. Establishing the relationship between the wild-type and vaccine strains in VZV infections among previously vaccinated individuals is crucial. Differences in the single nucleotide polymorphisms (SNPs) among vaccine strains can be utilized to identify the strain. In this study, we employed nanopore sequencing to identify VZV strains and analyzed clinical samples.

METHODS

We retrospectively examined vesicle and cerebrospinal fluid samples from patients with VZV infections. One sample each of the wild-type and vaccine strains, previously identified using allelic discrimination real-time PCR and direct sequencing, served as controls. Ten samples with undetermined VZV strains were included. After DNA extraction, a long PCR targeting the VZV ORF62 region was executed. Nanopore sequencing identified SNPs, allowing discrimination between the vaccine and wild-type strains.

RESULTS

Nanopore sequencing confirmed SNPs at previously reported sites (105,705, 106,262, 107,136, and 107,252), aiding in distinguishing between wild-type and vaccine strains. Among the ten unknown samples, nine were characterized as wild strains and one as a vaccine strain. Even in samples with low VZV DNA levels, nanopore sequencing was effective in strain identification.

CONCLUSION

This study validates that nanopore sequencing is a reliable method for differentiating between the wild-type and vaccine strains of VZV. Its ability to produce long-read sequences is remarkable, allowing simultaneous confirmation of known SNPs and the detection of new mutations. Nanopore sequencing can serve as a valuable tool for the swift and precise identification of wild-type and vaccine strains and has potential applications in future VZV surveillance.

MicroRNA expression profiling of urine exosomes in children with congenital cytomegalovirus infection

Congenital cytomegalovirus (cCMV) infection can damage the central nervous system in infants; however, its prognosis cannot be predicted from clinical evaluations at the time of birth. Urinary exosomes can be used to analyze neuronal damage in neuronal diseases. To investigate the extent of neuronal damage in patients with cCMV, exosomal miRNA expression in the urine was investigated in cCMV-infected infants and controls. Microarray analysis of miRNA was performed in a cohort of 30 infants, including 11 symptomatic cCMV (ScCMV), 7 asymptomatic cCMV (AScCMV), and one late-onset ScCMV cases, and 11 healthy controls (HC). Hierarchical clustering analysis revealed the distinct expression profile of ScCMV. The patient with late-onset ScCMV was grouped into the ScCMV cluster. Pathway enrichment analysis of the target mRNAs differed significantly between the ScCMV and HC groups; this analysis also revealed that pathways related to brain development were linked to upregulated pathways. Six miRNAs that significantly different between groups (ScCMV vs. HC and ScCMV vs. AScCMV) were selected for digital PCR in another cohort for further validation. Although these six miRNAs seemed insufficient for predicting ScCMV, expression profiles of urine exosomal miRNAs can reveal neurological damage in patients with ScCMV compared to those with AcCMV or healthy infants.

Comparison of plasma proteomic profiles of patients with Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis and infectious mononucleosis

Primary Epstein-Barr virus (EBV) infection occasionally causes EBV-infectious mononucleosis (EBV-IM) and EBV-hemophagocytic lymphohistiocytosis (EBV-HLH). Although EBV-IM is mostly mild and self-limiting, EBV-HLH is a life-threatening disease characterized by excessive immune activation. However, the pathogenesis of EBV-HLH is yet to be fully elucidated. A diagnostic biomarker for EBV-HLH is desirable because early diagnosis and treatment are critical for the effective management of patients. In this study, the proteomic profiling of plasma was performed using liquid chromatography-mass spectrometry to identify proteins specific to EBV-IM and EBV-HLH. Furthermore, pathway analysis was performed for the proteins upregulated in patients with EBV-IM and EBV-HLH. Compared to healthy controls, 63 and 18 proteins were upregulated in patients with EBV-IM and EBV-HLH, respectively. Pathway and process enrichment analyses revealed that the complement system was the most enriched category of upregulated proteins in EBV-IM, whereas proteins related to immune effector processes were the most enriched in EBV-HLH. Among the 18 proteins upregulated in EBV-HLH, seven were exclusive to EBV-HLH. These specific proteins were associated with three pathways, and apolipoprotein E was commonly found in all the pathways. Proteomic analysis may provide new insights into the host response to EBV infection and the pathogenesis of EBV-related diseases.

Next-generation sequencing-based detection of Ureaplasma in the gastric fluid of neonates with respiratory distress and chorioamnionitis

BACKGROUND

Respiratory distress is common in neonates admitted to neonatal intensive care units. Additionally, infectious diseases such as intrauterine infections or vertical transmission are important underlying causes of respiratory failure. However, pathogens often cannot be identified in neonates, and there are many cases in which antibacterial drugs are empirically administered. Next-generation sequencing (NGS) is advantageous in that it can detect trace amounts of bacteria that cannot be detected by culturing or bacteria that are difficult to cultivate. However, there are few reports on the diagnosis of infectious diseases using NGS in the neonatal field, especially those targeting respiratory distress.

OBJECTIVE

The purpose of our study was to investigate the microorganisms associated with neonatal respiratory distress and to determine whether less invasive collection specimens such as plasma and gastric fluid are useful.

METHODS

Neonates were prospectively recruited between January and August 2020 from Nagoya University Hospital. The inclusion criteria were as follows: 1) admission to the neonatal intensive care unit; 2) respiratory distress presentation within 48 h of birth; and 3) suspected infection, collection of blood culture, and administration of antibiotics. Plasma samples and blood cultures were simultaneously collected. Gastric fluid samples were also collected if the patient was not started on enteral nutrition. Information on the patients and their mothers were collected from the medical records. DNA was extracted from 140 µL of plasma and gastric fluid samples. DNA sequencing libraries were prepared, and their quality was analyzed. DNA libraries were sequenced using high-throughput NGS. The NGS data of plasma and gastric fluid samples were analyzed using the metagenomic pipeline PATHDET, which calculated the number of reads assigned to microorganisms and their relative abundance. Putative pathogens were listed.

RESULTS

Overall, 30 plasma samples and 25 gastric fluid samples from 30 neonates were analyzed. Microorganism-derived reads of gastric fluid samples were significantly higher than those of plasma samples. Transient tachypnea of the newborn was the most common cause of respiratory distress with 13 cases (43%), followed by respiratory distress syndrome with 7 cases (23%). There were 8 cases (29%) of chorioamnionitis and 7 cases (25%) of funisitis pathologically diagnosed. All blood cultures were negative, and only two gastric fluid cultures were positive for group B Streptococcus (Patient 15) and Candida albicans (Patient 24). Putative pathogens that met the positive criteria for PATHET were detected in four gastric fluid samples, one of which was group B Streptococcus from Patient 15. In the gastric fluid sample of Patient 24, Candida albicans were detected by NGS but did not meet the positive criteria for PATHDET. Cluster analysis of the plasma samples divided them into two study groups, and the indicator genera of each cluster (Phormidium or Toxoplasma) are shown in Figure 1. Clinical findings did not show any significant differences between the two groups. Cluster analysis of the gastric fluid samples divided them into three study groups, and the indicator genera of each cluster (Ureaplasma, Nostoc, and Streptococcus) are shown in Figure 2. The incidence rate of chorioamnionitis was significantly higher in Ureaplasma group than in the other two groups.

CONCLUSION

Gastric fluid may be useful for assessing neonatal patients with respiratory distress. To the best of our knowledge, this was the first study to reveal that the presence of Ureaplasma in the gastric fluid of neonates with respiratory distress was associated with chorioamnionitis. The early diagnosis of intra-amniotic infections using gastric fluid and its treatment may change the treatment strategy for neonatal respiratory distress. Screening for Ureaplasma in neonates with respiratory distress may reduce the need for empirical antibiotic administration. Further research is required to confirm these findings.

Proteomic Analysis Reveals Novel Plasma Biomarkers for Neurological Complications in Patients With Congenital Cytomegalovirus Infection

BACKGROUND

Congenital cytomegalovirus (cCMV) infection is a leading cause of nonhereditary neurological complications. When considering antiviral treatment, it is important to differentiate between symptomatic and asymptomatic patients. This study aimed to identify candidate plasma biomarkers for neurological complications of cCMV infection using proteomic analysis.

METHODS

This study retrospectively enrolled five patients with symptomatic cCMV infection, four with asymptomatic cCMV infection with isolated sensorineural hearing loss (SNHL), and five with asymptomatic cCMV infection. The plasma samples were collected during neonatal period. The peptides were analyzed using liquid chromatography-mass spectrometry. The concentrations of differentially expressed proteins were validated using an enzyme-linked immunosorbent assay.

RESULTS

A total of 456 proteins were identified and quantified. The levels of 80 proteins were significantly different between patients with and without cCMV-related symptoms including isolated SNHL. The levels of 31 proteins were significantly different between patients with and without neuroimaging abnormalities. The plasma concentrations of Fms-related receptor tyrosine kinase 4 in patients with cCMV-related symptoms were significantly higher than those in patients with asymptomatic cCMV infection. Moreover, plasma peptidylprolyl isomerase A levels were significantly higher in patients with neuroimaging abnormalities than in those without.

CONCLUSIONS

Proteomic analysis of patients with cCMV infection showed that Fms-related receptor tyrosine kinase 4 and peptidylprolyl isomerase A could be novel diagnostic biomarkers for neurological complications of cCMV infection.

Droplet digital PCR development for adenovirus load monitoring in children after hematopoietic stem cell transplantation

Human adenovirus (AdV) reactivation after hematopoietic stem cell transplantation (HSCT) is associated with life-threatening clinical manifestations. Real-time quantitative PCR (qPCR) has been widely used to measure AdV loads. However, qPCR has not been standardized for AdV. Droplet digital polymerase chain reaction (ddPCR) enables the absolute quantification of viral loads that is a novel pathogen detection technology. DdPCR would enable a more accurate AdV DNA detection compared to qPCR. In this study, ddPCR was developed for AdV DNA and compared its performance characteristics with qPCR. Then, AdV DNAemia incidence during the first 12 weeks after allogenic HSCT was retrospectively examined by qPCR and ddPCR in 97 HSCT episodes using the preserved 545 DNA samples. DdPCR showed better reproducibility and sensitivity, as well as equivalent quantifiability compared to qPCR. AdV DNA among HSCT patients was detected in 11 (2.0%) and 49 (9.0%) of 545 samples by qPCR and ddPCR, respectively. AdV DNA levels of >1000 copies/mL were observed in five cases by qPCR and/or ddPCR. However, two developed fulminant hepatitis and died, while other patients remained asymptomatic with subsequently undetectable AdV DNA. In conclusion, ddPCR was more sensitive and reproducible in detecting AdV DNA among pediatric HSCT recipients than qPCR. DdPCR represents the potential to provide a more accurate DNAemia detection, determine cutoff values for treatment initiation, and antiviral efficacy assessment.

542. Nanopore and Illumina sequencing for pathogen metagenomics and host transcriptomics of cerebrospinal fluid in infantile central nervous system infections

Background

Infantile central nervous system infections (CNSIs) can be life-threatening and severe sequelae can be observed in encephalitis and bacterial meningitis. The causative microorganism is unknown in > 40% of patients with aseptic infections. This study aimed to analyze metagenome for detection of pathogen, and transcriptome for host reaction of infection in a single cerebrospinal fluid (CSF) sample using two different next-generation sequencing (NGS) platforms, Illumina and Nanopore.

Methods

Twenty-eight CNSIs patients (< 12 months), treated between June 2012 and April 2020, were enrolled. A total of 49 clinical samples (28 CSF and 21 blood) from 28 patients were collected. Extracted RNA, which was obtained from 23 CSF in sufficient quantities, was sequenced using both Nanopore and Illumina platforms to compare their performances in the detection of pathogens. Human-derived reads subtracted during pathogen detection were used for host transcriptomic analysis from both Nanopore and Illumina sequencing. All the extracted DNA from 28 CSF and 21 blood, was sequenced using Illumina sequencer for the detection of pathogens. Data analysis was performed on the in-house PATHDET pipeline.

A flowchart for pathogen detection and transcriptome analysis

Pathogen detection was performed on the in-house PATHDET pipeline and transcriptome analysis was performed by using the secondary outputs.

Results

RNA sequencing of CSF samples in 23 cases revealed potential viral pathogens in 10 cases: coxsackievirus B5 (4 cases), coxsackievirus B4 (3 cases), coxsackievirus B2 (1 case), echovirus E7 (1 case), and human parechovirus 3 (1 case). DNA sequencing was performed in 28 cases using Illumina sequencing, and Proteus mirabilis (1 case, consistent with the culture test) and human parvovirus B19 (1 case) were detected. The results of Nanopore sequencing and Illumina sequencing were consistent. However, the mapping coverage and depth to the detected pathogen genome of Nanopore sequencing was superior to that of Illumina sequencing. MX1, ISG15, and OAS1 were differentially expressed genes in patients with identified pathogens via metagenomic NGS, both the Nanopore and Illumina sequencing, and were associated with antiviral roles in innate immunity.

A pie chart for patients with central nervous system infections (CNSIs)

Results of next-generation sequencing (NGS) and the detected pathogen candidates using DNA/RNA workflows.

Performance of Nanopore and Illumina sequencing for pathogen genome mapping

The sequencing output, which is 100,000 reads randomly extracted from original sequencing reads, was mapped to the pathogen reference genome to determine (A) mapping coverage and (B) mapping depth.

Volcano plot of all genes analyzed in Nanopore and Illumina sequencing

Volcano plots showing differentially expressed genes in the cerebrospinal fluid between identified-pathogen and unidentified-pathogen samples from (A) Nanopore sequencing and (B) Illumina RNA sequencing.

Conclusion

The use of Nanopore sequencing for metagenomic diagnostics of CSF samples should help to understand both pathogens and host immune responses of CNSI and could shed light on the pathogenesis of these infections.

Disclosures

All Authors: No reported disclosures.

Performance of Nanopore and Illumina metagenomic sequencing for pathogen detection and transcriptome analysis in infantile central nervous system infections

Background

Infantile central nervous system infections (CNSIs) can be life-threatening and cause severe sequelae. However, the causative microorganism remains unknown in >40% of patients with aseptic infections. This study aimed to analyze the metagenome for detection of pathogens and the transcriptome for host immune responses during infection in a single cerebrospinal fluid (CSF) sample using 2 different next-generation sequencing (NGS) platforms, Nanopore and Illumina.

Methods

Twenty-eight CNSIs patients (<12 months) were enrolled, and 49 clinical samples (28 CSF and 21 blood) were collected. The DNA extracted from all 49 samples was sequenced using the Illumina sequencer for the detection of pathogens. Extracted RNA was obtained in sufficient quantities from 23 CSF samples and subjected to sequencing on both Nanopore and Illumina platforms. Human-derived reads subtracted during pathogen detection were used for host transcriptomic analysis from both Nanopore and Illumina sequencing.

Results

RNA metagenomic sequencing using both sequencing platforms revealed putative viral pathogens in 10 cases. DNA sequencing using the Illumina sequencer detected 2 pathogens. The results of Nanopore and Illumina RNA sequencing were consistent; however, the mapping coverage and depth to the detected pathogen genome of Nanopore RNA sequencing were greater than those of Illumina. Host transcriptomic analysis of Nanopore sequencing revealed highly expressed genes related to the antiviral roles of innate immunity from pathogen-identified cases.

Conclusions

The use of Nanopore RNA sequencing for metagenomic diagnostics of CSF samples should help to elucidate both pathogens and host immune responses of CNSI and could shed light on the pathogenesis of these infections.

Post-exposure prophylaxis to prevent varicella in immunocompromised children

Background

Varicella-zoster virus (VZV) infection can cause life-threatening events in immunocompromised patients. Post-exposure prophylaxis (PEP) is required to prevent secondary VZV infection. Limited evidence is available for the use of acyclovir (ACV)/valacyclovir (VCV) as PEP.

Methods

Herein, we retrospectively analyzed immunocompromised paediatric patients with significant exposure to VZV. Patients administered PEP were categorized into four groups: 1) ACV/VCV group; 2) intravenous immunoglobulin (IVIG) group; 3) ACV/VCV/IVIG group; 4) vaccine group.

Results

Among 69 exposure events, 107 patients were administered PEP (91, ACV/VCV; 16, ACV/VCV/IVIG) and 10 patients did not receive PEP (non-PEP group). The index case was diagnosed based on clinical symptoms in 55 cases (79.7%). Fourteen cases (20.3%) were confirmed using direct virological diagnostic procedures. In the PEP group, only 2 patients (2.2%) developed secondary VZV infections. Additionally, 2 patients in the non-PEP group (20.0%) developed secondary VZV infection. The incidence of secondary VZV infection was significantly lower in the PEP group than in the non-PEP group (P=0.036). Among patients administered PEP, no antiviral drug-induced side effects were detected.

Conclusions

Antiviral agents administered as PEP are effective and safe for preventing VZV infections in immunocompromised patients. Rapid virological diagnosis of index cases might allow efficient administration of PEP after significant exposure to VZV infection.

Detection of antiviral drug resistance in patients with congenital cytomegalovirus infection using long-read sequencing: a retrospective observational study

BACKGROUND

Congenital human cytomegalovirus (cCMV) infection can cause sensorineural hearing loss and neurodevelopmental disabilities in children. Ganciclovir and valganciclovir (GCV/VGCV) improve long-term audiologic and neurodevelopmental outcomes for patients with cCMV infection; however, antiviral drug resistance has been documented in some cases. Long-read sequencing can be used for the detection of drug resistance mutations. The objective of this study was to develop full-length analysis of UL97 and UL54, target genes with mutations that confer GCV/VGCV resistance using long-read sequencing, and investigate drug resistance mutation in patients with cCMV infection.

METHODS

Drug resistance mutation analysis was retrospectively performed in 11 patients with cCMV infection treated with GCV/VGCV. UL97 and UL54 genes were amplified using blood DNA. The amplicons were sequenced using a long-read sequencer and aligned with the reference gene. Single nucleotide variants were detected and replaced with the reference sequence. The replaced sequence was submitted to a mutation resistance analyzer, which is an open platform for drug resistance mutations.

RESULTS

Two drug resistance mutations (UL54 V823A and UL97 A594V) were found in one patient. Both mutations emerged after 6 months of therapy, where viral load increased. Mutation rates subsided after cessation of GCV/VGCV treatment.

CONCLUSIONS

Antiviral drug resistance can emerge in patients with cCMV receiving long-term therapy. Full-length analysis of UL97 and UL54 via long-read sequencing enabled the rapid and comprehensive detection of drug resistance mutations.

Endothelial cell-binding antibodies in patients with systemic lupus erythematosus

Abstract The implications of endothelial cell-binding IgG antibodies (EC IgG) in systemic lupus erythematosus (SLE) was evaluated by determining level of EC IgG in sera from 112 SLE patients. The serum EC IgG level was determined by the cyto-ELISA method using human umbilical vein endothelial cells (HUVEC), human microvascular endothelial cells (HMVEC), and aortic endothelial cells (HAEC) as antigens. The levels of EC IgG were significantly higher among patients with SLE than among healthy control subjects (P < 0.001), and 68% (76/112) of SLE patients were shown to be EC IgG-positive. In patients with active lupus nephritis, the level of EC IgG was statistically and significantly elevated compared with those without lupus nephritis (P < 0.05). Negative correlations between EC IgG level and levels of CH50, C3, and lymphocyte count were revealed (P < 0.05, P < 0.005, and P < 0.05, respectively). When clinical course was evaluated, the levels of EC IgG correlated with disease activity. Definitive correlations in antibody levels between HUVEC and HMVEC, and between HUVEC and HAEC were revealed (both P < 0.0001). The results of this study revealed that the EC IgG in patients with SLE was involved in the onset of clinical manifestation, especially in patients with active lupus nephritis.

Soluble CD154 in rheumatoid arthritis: elevated plasma levels in cases with vasculitis

OBJECTIVE

To determine the levels of soluble CD154 (sCD154) in the plasma of patients with rheumatoid arthritis (RA) and rheumatoid vasculitis (RV). and to examine the relationship between the levels of sCD154 in plasma and the clinical variables.

METHODS

Levels of sCD154 were quantified in 39 plasma samples from patients with RA, including 9 patients who were also diagnosed with RV, and compared with those of 20 healthy subjects. An ELISA was established and specificity of the ELISA was tested by control ELISA using isotype-matched IgG and preabsorption assay. The titers of IgM and IgG rheumatoid factor (IgM-RF, IgG-RF) for each patient were determined simultaneously, and values of other laboratory variables were also determined.

RESULTS

Levels of sCD 154 in plasma were higher in patients with RA than in the healthy subjects (p < 0.02). Compared with RA patients without vasculitis, patients with RV had significantly higher levels of sCD154 in their plasma (p < 0.001). Control ELISA and absorption assay of sCD154 indicated that our ELISA system was capable of measuring plasma sCD154 in RA patients. Levels of sCD154 in RA plasma correlated significantly with both IgM-RF and IgG-RF titers (r = 0.64 and 0.61, respectively, both p < 0.001). The levels of sCD154 decreased after commencement of treatment for vasculitis in cases with RV.

CONCLUSION

We identified the presence of sCD154 in RA plasma, with especially high levels in cases with vasculitis. Correlation between sCD154 and RF titers indicates the CD154-CD40 pathway is likely related to pathogenic RF production.

In situ observation of superdislocation motion in pre-strained Ni3Ge single crystals

Dislocation structures and their effect on the superdislocation motion in Ni3Ge single crystals have been studied by two-step deformation. In these tests either octahedral or cube slips were induced by prestraining. A difference in the induced dislocation structure is found to cause a notable change in the second deformation step depending on the combination of the stress axes. In order to understand the orientation sensitive hardening, in-situ deformation experiments have been made on the prestrained specimens in a high voltage electron microscope. Besides observation of the structural change due to dislocation motion, electron irradiation, which decorates antiphase boundary tubes, is utilized to trace the history of the rapid dislocation motion. Based on these observations, the origin of the anomalous strengthening in Ni3Ge is discussed with particular interest in the fine and non-planar dislocation structures induced by cross slips and dislocation-dislocation interactions.

Pentoxifylline induces the shedding of L-selectin on polymorphonuclear cells by stimulation via adenosine receptor as well as by the inhibition of phosphodiesterase

Abstract We investigated the effects of pentoxifylline (PTX) on the expression of L-selectin on polymorphonuclear leukocytes (PMN). PTX induced the down-regulation of L-selectin expression in dose- and time-dependent manner. The measurement of soluble L-selectin in the culture medium by ELISA indicated that the down-regulation of L-selectin expression by PTX was due to the shedding of L-selectin from PMN. The mechanism by which PTX induced the shedding of L-selectin was investigated. The concentration of intracellular cyclic AMP (cAMP) was increased after treatment of PMN with PTX. However, an elevation of cAMP induced by dibutyryl cAMP (dbcAMP) as well as other methylxanthine derivatives (caffeine, aminophylline, and theophylline) did not induce the shedding of L-selectin. Although stimulation of the adenosine receptor with 5'-N-ethylcarboxamidoadenosine (NECA) or 5'-(N-cyclopropyl)-carboxamido-adenosine (CPCA) adenosine receptor agonists did not induce the shedding of L-selectin, shedding of L-selectin was demonstrated when PMN was incubated simultaneously with rolipram, a phosphodiesterase (PDE) inhibitor, and CPCA. Moreover, shedding of L-selectin induced by PTX was attenuated by aminophylline, an adenosine receptor antagonist. These results indicated that PTX induces the shedding of L-selectin on PMN by stimulation via the adenosine receptor as well as inhibition of PDE.

Effect of immune complexes in serum from patients with rheumatoid vasculitis on the expression of cell adhesion molecules on polymorphonuclear cells

OBJECTIVE

Immune complexes (IC) are frequently detected in patients with rheumatoid vasculitis (RV). To explore the pathogenic role of IC in the development of vasculitis among patients with rheumatoid arthritis (RA), we examined the effect of IC on the expression of cell adhesion molecules (CAM) on polymorphonuclear cells (PMN).

METHODS

PMN from healthy volunteers were incubated with the sera from 26 patients with RA including 9 patients with RV, and the expression of CAM on the PMN was assessed by flow cytometry.

RESULTS

We found that 67% (6/9) of the serum samples from RV patients and 18% (3/17) of the samples from RA patients without RV revealed up-regulated CD11b expression. On the other hand, 89% (8/9) of the samples from RV patients and 12% (2/17) of the samples from RA patients without RV revealed up-regulated CD18 expression. However, the expression of CD11a was not affected. Up-regulation of CD11b and CD18 on PMN was also induced by the immunoglobulin G (IgG) fraction of the sera of RV patients. Moreover, L-selectin expression on PMN was down-regulated by the sera or IgG of some patients with RV. These changes in CAM expression on PMN induced by IgG of RV patients were not observed when PMN were incubated with the IgG of RV patients from which the IC formed by IgG had been removed.

CONCLUSION

These results suggest that IC formed by IgG in patients with RA are involved in the development of vasculitis by affecting the expression of CAM on PMN.

Cholangiolocellular carcinoma of the liver: CT and MR findings

The authors report two cases of surgically proved cholangiolocellular carcinoma of the liver. Marked contrast enhancement was observed at the periphery of the tumor on CTs and MRIs obtained during the hepatic arterial and portal venous phases, with concentric filling on the delayed images. On T1-weighted and T2-weighted MRIs, the tumor was, respectively, hypointense and hyperintense, with a central hypointense area. Therefore, helical CT and MRI features of these cholangiolocellular carcinomas were thought to be similar to those of cholangiocarcinoma.

Fas ligand-mediated exocrinopathy resembling Sjögren's syndrome in mice transgenic for IL-10

Although IL-10 has been implicated in the pathogenesis of several autoimmune diseases, the mechanisms by which this cytokine mediates inflammatory lesions remain to be elucidated. Exocrine gland destruction is an important early step in the development of Sjögren's syndrome. To better understand the role of IL-10 in Sjögren's syndrome, we made transgenic mice in which the mouse IL-10 gene was regulated by the human salivary amylase promoter. Transgenic expression of IL-10 induced apoptosis of glandular tissue destruction and lymphocyte infiltration consisting primarily of Fas-ligand (FasL)+ CD4+ T cells, as well as in vitro up-regulation of FasL expression on T cells. These data suggest that overexpression of IL-10 in the glands and their subsequent Fas/FasL-mediated bystander tissue destruction is a causal factor in the development of this disease.

Isolation and mapping of a polymorphic CA repeat sequence at the human interleukin 6 locus

A polymorphic dinucleotide (CA) sequence was isolated from a genomic clone containing the human interleukin 6 (interferon beta-2) gene and was mapped to 7p21. This polymorphism will be useful in the genetic study of disorders affecting the inflammation process, calcium metabolism, and hematologic malignancies.

Monoclonal anti-cardiolipin antibodies from New Zealand Black x New Zealand White F1 mice react to thrombomodulin

The reactivity with and affinity for thrombomodulin (TM) of monoclonal anti-cardiolipin Abs (MoaCL), derived from a New Zealand Black x New Zealand White F1 (NZB/W F1) mouse, were studied to investigate the pathogenicity of anti-cardiolipin Abs (aCL). Four of eighteen MoaCL were found to react with rabbit TM when examined using ELISA. These four MoaCL also reacted with synthetic peptide that included the epidermal growth factor-like domain of human TM, a binding site for thrombin. The reaction with TM of these four MoaCL was inhibited by bovine thrombin. When the affinity for TM of the MoaCL was determined, the dissociation constants (Kd) ranged from 4.8 x 10(-9) to 4.7 x 10(-8) M. By contrast, examination of the affinity for cardiolipin (CL) gave values from 8.3 x 10(-6) to 7.4 x 10(-5) M. Thus, these MoaCL reacted to TM with a higher affinity than to CL. Moreover, these MoaCL also bound to TM on HUVEC and down-regulated the expression level of TM on the surface of HUVEC due to internalization of TM. The binding of thrombin to TM is known to initiate rapid protein C activation, and complexes of activated protein C and protein S show anticoagulatory activity. Thus, the present studies suggest that certain pathogenic aCL cross-react with TM and induce down-regulation of TM on endothelial cells, followed by induction of thrombosis.

K+ channel-opening action contributes to the preventive effects of nicorandil on U46619-induced vasoconstriction of canine large coronary arteries in vivo

The antispasmogenic effects of nicorandil on epicardial coronary artery vasoconstriction were compared with those of a K+ channel opener, cromakalim, and a nitrovasodilator, nitroglycerin, in open-chest dogs. Intracoronary administration of U46619 (0.5-1.0 micrograms), a stable thromboxane A2 analogue, reduced the external diameter of the left circumflex coronary artery with no marked alternations in systemic hemodynamics. This U46619-induced vasoconstriction of large epicardial coronary arteries was dose-dependently prevented by the intracoronary infusion of nicorandil (1-10 micrograms/kg/min), cromakalim (0.03 micrograms/kg/min) and nitroglycerin (1 micrograms/kg/min). After pretreatment with glibenclamide (3 mg/kg, i.v.), and ATP-sensitive K+ channel blocker, these effects of nicorandil and cromakalim were inhibited significantly, whereas the response to nitroglycerin remained unchanged. Nicorandil (3 micrograms/kg/min), cromakalim (0.03 micrograms/kg/min) and nitroglycerin (1 micrograms/kg/min) increased coronary blood flow. However, the inhibitory effects of each drug on the U46619-induced vasoconstriction were not influenced by the partial occlusion of the left circumflex coronary artery, which kept coronary blood flow constant. This indicates a direct antispasmogenic effect of K+ channel openers, which is independent of that mediated by the response to flow. Furthermore, our results suggest that, by this effect, nicorandil protects large coronary arteries from U46619-induced vasoconstriction.

A comparative study of whole-blood platelet aggregation in laboratory animals: its species differences and comparison with turbidimetric method

We undertook a systematic comparison of whole-blood platelet aggregation concerning species difference of commonly used laboratory animals (rabbits, guinea pigs, rats and dogs), agonist difference (collagen, ADP and platelet activating factor [PAF] and technical difference against a traditional method of turbidimetry. Collagen-induced aggregation with whole-blood aggregometry was less variable among species tested and was similar to the results obtained by turbidimetry, which measures platelet aggregation in citrated plasma. In contrast, whole-blood aggregometry in responses to ADP and PAF showed marked species difference, being different from turbidimetry. Our results provide species difference among laboratory animals and suggest that the modulations of platelet aggregation by other blood elements probably differ in each species and with stimulating agonists.

Flush induced by fluoroquinolones in canine skin

The flush induced by two fluoroquinolone antibacterial agents, balofloxacin and ofloxacin, was studied in beagle dogs. Intradermal injection of the fluoroquinolones at concentrations above 10(-5) M produced a localized flushed area. The flush responses to fluoroquinolones were inhibited by co-administration with H2-antagonist(s) (ranitidine or cimetidine), but not with H1-antagonist(s) (mepyramine or chlorpheniramine). Similar inhibitory effects of these H2-antagonists were observed for the response to histamine. The flush responses to fluoroquinolones were inhibited by a local pretreatment with compound 48/80 administered to deplete the local stores of mast cell-bound histamine. When the fluoroquinolones were orally administered at a dose of 400 mg/kg, the concentration of histamine in plasma was increased, being accompanied by systemic erythema. These results indicate that the flush induced by fluoroquinolones is mediated by histamine release from canine cutaneous mast cells and H2-receptor stimulation.

Pressor response induced by the hippocampal administration of neostigmine is suppressed by M1 muscarinic antagonist

We investigated the roles played by three muscarinic receptors (M1, M2, and M3) in the pressor response with bradycardia that followed the injection of neostigmine (5 x 10(-8) mol) into the hippocampus of anesthetized rats. These changes were blocked by the co-administration of methylatropine (5 x 10(-8) mol). The intrahippocampal injection of pirenzepine (M1 antagonist) (5 x 10(-9) - 5 x 10(-7) mol) suppressed the neostigmine-induced pressor response dose-dependently. However injection of gallamine (M2 antagonist) (5 x 10(-8) - 5 x 10(-7) mol) and of 4-DAMP (M1 and M3 antagonist) (5 x 10(-8) - 5 x 10(-7) mol) did not suppress this hypertensive response. These findings suggest that the neostigmine-induced pressor response with bradycardia is mediated through the M1 muscarinic receptor subtype.

Gastrointestinal motor inhibition by exogenous human, salmon, and eel calcitonin in conscious dogs

Effects of synthetic eel (E-), salmon (S-), and human (H-) calcitonin (CT) on gastrointestinal motility were studied in conscious beagle dogs, which had been implanted with strain gauge force transducers. Intramuscular administration of E-, S-, or H-CT interrupted gastric migrating motor complexes, digestive pattern, and gastric emptying. The order of potency was E-CT = S-CT > H-CT. Motor inhibition induced by CT occurred independently of plasma immunoreactive motilin levels or hypocalcemia. In addition, E-CT and S-CT induced vomiting without a retrograde giant contraction (RGC) during the postprandial state. Apomorphine or CuSO4 initiated RGC prior to vomiting. RGC induced by apomorphine was inhibited by pretreatment with E-CT as well as hexamethonium, atropine, or surgical vagotomy. E-CT showed no inhibitory effect on nicotine stimulated contraction of isolated guinea-pig ileum. These results suggest that peripherally administered CT inhibits canine gastrointestinal motility at the central nervous system level by lowering vagal activity.

Effects of ginsenosides on impaired performance induced in the rat by scopolamine in a radial-arm maze

The effects of ginsenosides Rg1, Rd and Rb1 on impaired performance induced in the rat by scopolamine were examined in a radial-arm maze. Scopolamine caused a reduction in the number of initial correct responses in the maze. A single IP injection of Rg1, but not Rd or Rb1, prevented the reduction. The inhibition of the reduction in initial correct responses was associated with a bell-shaped dose-response curve for Rg1. A lesion in the medial septum caused spatial learning deficits. Rg1 did not overcome these deficits. It is suggested that cholinergic neurons in the medial septum are involved in the ameliorative effect of Rg1 on impaired performance induced by scopolamine.

Effects of ionic and nonionic contrast media on cardiohemodynamics and quality of radiographic image during canine angiography

Cardiovascular responses and radiographic image quality during cerebral angiography, aortofemoral angiography and left ventriculography with nonionic ioxilan, iohexol or iopamidol were compared with those of ionic sodium meglumine diatrizoate in pentobarbital anesthetized dogs. Injection of all contrast media caused cardiovascular changes to a greater or lesser degree, e.g., hypotension, bradycardia, tachycardia, a decrease in left ventricular pressure (LVP) and its first derivative (dP/dt), and prolongation of the P-Q and Q-T intervals. Ionic diatrizoate had a greater effect on cardiovascular parameters than nonionic contrast media during angiography in all areas. Moreover, diatrizoate produced cardiac arrhythmias and prominent changes in blood rheology concerned with blood viscosity and deformability of the erythrocyte. The cause of various effects of contrast media seemed to lie mainly in osmolality, viscosity and partially ionic additives. The radiographic image quality of all of the contrast media used was similar, but nonionic ioxilan and iohexol with lower iodine content and low osmolality gave better radio opacity than ionic diatrizoate in cerebral angiography. These results suggested that nonionic contrast media should be recommended as a diagnostic tool for both animals and human patients in poor health.

Postprandial change in canine blood viscosity

1. Postprandial variation in blood viscosity was studied in beagle dogs. 2. Blood viscosity increased following feeding. This change was caused by haematocrit elevation, which resulted mainly from splenic contraction. 3. Haemoconcentration, plasma viscosity and erythrocyte deformability did not contribute to the postprandial increment in blood viscosity.

Are diabetic hearts more resistant to ischemia/reperfusion injury?

The present study was designed to investigate the cardiac impairment during ischemia/reperfusion injury in rats with streptozotocin-induced diabetes vs controls. Male rats were divided into three groups: controls, one-week diabetic rats (1wDM) and four-week diabetic rats (4wDM). In the isolated working heart, left ventricular developed pressure (LVDP), left ventricular end-diastolic pressure (LVEDP), and maximum positive and negative dP/dt were measured before ischemia and after 20 min of global ischemia followed by 30 min reperfusion. In the pre-ischemic state, hearts of 4wDM showed a significant (p < 0.05) depression of the maximum positive and negative dP/dt compared with those of controls and 1wDM. There were no significant differences in LVDP and LVEDP among the three groups. The incidence of reperfusion-induced ventricular fibrillation (VF) was 75% for controls, 15% for 1wDM rats, and 27% for 4wDM rats. In hearts without reperfusion-induced VF, there were no differences in the three groups, between the pre- and post-ischemic values in LVDP, LVEDP, and maximum positive and negative dP/dt. These findings suggest that diabetic hearts exhibit no susceptibility to ischemia/reperfusion injury.

Stimulation of muscarinic cholinoceptive neurons in the hippocampus evokes a pressor response with bradycardia

The injection of neostigmine into the hippocampus of anesthetized rats increased the mean arterial blood pressure (17% of baseline after 60 min injection) and decreased the heart rate (24% of baseline after 60 min injection). These changes were blocked by the co-administration of methylatropine into the hippocampus. Intrahippocampal injection of neostigmine stimulated the secretion of epinephrine and norepinephrine. Adrenodemedullation did not suppress the increase in blood pressure and the decrease in heart rate. It is concluded that the stimulation of muscarinic cholinoceptive neurons in the hippocampus evokes a hypertensive response via an increase in sympathetic drive to the heart and peripheral vasculature, with bradycardia possibly mediated via the parasympathetic system.

Circadian changes in arginine vasopressin level in the suprachiasmatic nuclei in the rat

Arginine vasopressin (AVP) neurons were preferentially localized in the dorsomedial part of the suprachiasmatic nucleus (SCN). To know the role of AVP neurons in the SCN, male rats were kept under a normal light-dark cycle (L-D), or under constant darkness (D-D) for 20 days. In L-D condition, AVP levels in the SCN showed the circadian change. In D-D condition, the patterns in AVP levels showed a free-running rhythm, and an about 12-h shift per 20 days. This result suggests that the activity of AVP neurons may be closely associated with the endogenous circadian rhythm of the SCN.

Changes in arginine vasotocin content in the pituitary of the Medaka (Oryzias latipes) during osmotic stress

Changes in the arginine vasotocin (AVT) neurons of the medaka, Oryzias latipes, during osmotic stress were studied by means of immunohistochemistry and radioimmunoassay. AVT neurons were identified by their immunoreactivity to anti-arginine vasopressin serum, which crossreacts with AVT. When freshwater (FW)-adapted fish were transferred to seawater (SW), the number of immunoreactive magnocellular neurons decreased, while the cell nuclear size increased. AVT content in the pituitary significantly decreased 2 hr or 1 day after transfer to SW, but returned to approximately the initial level 1 week after transfer. However, when SW-adapted fish were transferred to FW, the number of immunoreactive magnocellular neurons increased from 1 hr after readaptation to FW, but the cell nuclear size failed to show significant changes. AVT content in the pituitary significantly increased 1 or 2 hr after transfer. These results seem to indicate that AVT secretion in the medaka was temporarily accelerated by exposure to SW and inhibited immediately after transfer to FW.

Subtypes of muscarinic receptors in pancreatic exocrine secretion in anesthetized dog

Characterization of muscarinic receptor subtypes on the dog pancreas in situ was examined by using specific muscarinic receptor antagonists to study pancreatic exocrine secretion. Bethanechol caused an increase in pancreatic exocrine secretion, with a high concentration of protein and little effect on bicarbonate concentration. Thus bethanechol may mainly affect the muscarinic receptors of the acinar cells. Bethanechol-stimulated secretion was inhibited by pirenzepine (a specific M1 muscarinic antagonist), 4-diphenylacetoxy-N-methylpiperidine methobromide (4-DAMP, a specific M3 muscarinic antagonist), and atropine (a mixed muscarinic receptor antagonist). However, [11-[[2-(diethylamino)methyl]-1-piperidinyl]acetyl]-5, 11- dihydro-6H-pyrido[2,3-b][1,4]benzo-diazepine-6-one (AF-DX 116, a specific cardioselective M2 antagonist) did not have any effects on bethanechol-stimulated secretion. Increased protein secretion in pancreatic juice stimulated by bethanechol was significantly inhibited by 4-DAMP and atropine and was suppressed by pirenzepine, but was not modified by AF-DX 116. Bicarbonate concentration was not modified by these antagonists. 4-DAMP, atropine, and pirenzepine caused a progressive parallel rightward shift in the dose-response curve of pancreatic secretion for bethanechol. Schild analysis of the data indicated a pA2 value of 8.7 for 4-DAMP, 7.9 for atropine, and 6.2 for pirenzepine, respectively. Thus 4-DAMP has 7.5 times and 440 times greater potency than atropine and pirenzepine to inhibit bethanechol-stimulated secretion. The slope of the Schild regression line was not different from 1. These results suggest that inhibitions of bethanechol-stimulated pancreatic secretion are competitive for 4-DAMP, atropine, and pirenzepine and that bethanechol-stimulated pancreatic secretion is mediated by M3 muscarinic receptors in dogs.

Alpha-adrenoceptor antagonistic effects and antihypertensive activity of SGB-1534 in conscious normotensive and deoxycorticosterone acetate (DOCA)-salt hypertensive dogs: comparison with prazosin

In conscious normotensive and deoxycorticosterone acetate (DOCA)-salt hypertensive dogs, alpha-adrenoceptor antagonistic and antihypertensive actions of SGB-1534, given orally, were compared with those of prazosin. SGB-1534 and prazosin did not markedly influence systemic blood pressure (SBP) and heart rate (HR) in normotensive dogs. These alpha 1-adrenoceptor antagonists inhibited SBP and HR increases induced by i.v. adrenaline in a dose-dependent manner. In DOCA-salt hypertensive dogs, persistent hypotension, accompanied by a reflex tachycardia, occurred after oral administration of SGB-1534 and prazosin. The hypotensive activity of SGB-1534 was much more potent in magnitude and duration than that of prazosin. In isolated canine mesenteric and femoral arteries, SGB-1534, compared to prazosin, elicited a more potent inhibition on the contractile response to a relatively selective alpha 1-adrenoceptor agonist, phenylephrine. It appears that the antihypertensive activity of SGB-1534, like prazosin, is nearly in parallel with its alpha 1-adrenoceptor antagonistic effect.

Effects of DN-9693, a synthesized phosphodiesterase inhibitor, on pancreatic exocrine secretion in dogs

The effects of DN-9693, a synthesized phosphodiesterase inhibitor, on the secretion of pancreatic juice were investigated in preparations of the isolated and blood-perfused dog pancreas. DN-9693 injected intraarterially caused a dose-dependent increase in the secretion of pancreatic juice and decrease in the perfusion pressure. The threshold doses to increase the pancreatic secretion and to decrease the perfusion pressure were about 100 micrograms and 1 microgram, to decrease the perfusion pressure were about 100 micrograms and 1 micrograms, respectively. Thus, the secretory response was less effective than the vascular response. The secretory activity of DN-9693 (0.3 mg) was approximately equal to that of 0.03 mg of 3-isobutyl-1-methylxanthine, 0.5 mg of papaverine, 5 mg of theophylline, 0.08 0.5 mg of papaverine, 5 mg of theophylline, 0.08 units of secretin and 0.2 units of cholecystokinin. The concentration of bicarbonate in the pancreatic juice induced by DN-9693 was increased, but protein concentration was not. DN-9693-induced pancreatic secretion was not modified by pretreatments with phentolamine, propranolol, atropine, sulpiride and cimetidine. Secretin-induced pancreatic secretion was significantly potentiated by infusion of DN-9693 (10 micrograms/min), but cholecystokinin-induced one was not. From these results, it is concluded that DN-9693 may produce an increase in pancreatic secretion by acting directly on the pancreatic exocrine gland of the dog, which might be mediated through an increase of intracellular cyclic AMP concentration by inhibiting phosphodiesterase activity.

Central alpha 2 adrenoceptor-mediated pancreatic exocrine response to yohimbine in anesthetized dog

Effects of yohimbine on the secretion of pancreatic juice in anesthetized dogs were investigated. Intravenous yohimbine (0.1-1 mg/kg) caused dose-dependent increases in the secretion of pancreatic juice and vasodilation. However, intra-arterial yohimbine (0.3-1 mg) did not cause any secretory responses. The secretory activity of 0.3 mg/kg of yohimbine was approximately equal to that of 0.04 U/kg of secretin and 40 mg/kg of 2-deoxy-D-glucose (2-DG). Secretory responses to yohimbine were inhibited by pretreatment with clonidine or atropine and abolished by vagotomy. The concentration of protein in the pancreatic juice induced by yohimbine was increased, but the bicarbonate concentration was scarcely changed. These results indicate that yohimbine stimulates, at least in part, pancreatic exocrine secretion by acting on the central alpha 2 adrenoceptor in the dog.

Effects of three purine-related compounds on pancreatic exocrine secretion in the dog

The effects of adenosine, adenosine 5'-triphosphate (ATP) and inosine on pancreatic exocrine secretion were investigated in the vascularly isolated and self-haemoperfused dog pancreas. Drugs were injected close-arterially (i.a.) in a single bolus. These three purine-related compounds per se did not affect resting rate of pancreatic secretion and the concentrations of protein and bicarbonate in the resting juice. Graded doses of adenosine (0.1-1.0 mg, i.a.) and ATP (0.1-1.0 mg i.a.) administered 1 min prior to secretin (0.025 clinical units, i.a.) increased a secretin-stimulated secretory volume dose-dependently, and the effects of adenosine and ATP were reversed by pretreatments with theophylline (0.3 mg, i.a.). Inosine (1.0 mg, i.a.) affected neither secretin- nor dopamine-stimulated (3 micrograms, i.a.) pancreatic secretion. Adenosine and ATP did not affect dopamine-stimulated pancreatic secretion. These results suggest that adenosine and ATP (or terminal phosphate hydrolyzed derivatives) enhance secretin-stimulated pancreatic exocrine secretion through 'P1' purine receptors in the exocrine cells, without conversion to inosine.

Blocking effects of verapamil on pancreatic exocrine secretion induced by dopamine in the dog

The effects of verapamil on the dopamine-induced pancreatic exocrine secretion were investigated in the isolated and blood-perfused canine pancreas at a constant flow rate in situ. All drugs were given intra-arterially. Dose-related increases in the volume of pancreatic secretion induced by dopamine (1-10 micrograms) were reduced by infusion of 50 and 100 micrograms/min of verapamil, but were not affected by diltiazem (100 micrograms/min) and dilazep (100 micrograms/min) infusions. Protein concentration in pancreatic juice induced by dopamine was decreased significantly by the infusion of verapamil, diltiazem and dilazep, but bicarbonate concentration was not. These results suggest that verapamil reduced the dopamine-induced pancreatic secretion by virtue of its dopamine antagonist activity and inhibited protein secretion by virtue of its calcium channel blocking action.

Adenosine potentiates secretin-stimulated pancreatic exocrine secretion in the dog

Pretreatment with graded doses of adenosine (0.1-1.0 mg), injected close-arterially (i.a.) to the vascularly isolated and self-hemoperfused dog pancreas, increased secretin (0.025 units i.a.)-stimulated secretory volume dose dependently and this effect of adenosine was reversed by further pretreatment with theophylline (0.3 mg i.a.). Adenosine itself did not affect the rate of resting secretion and the concentrations of protein and bicarbonate of the resting pancreatic juice. Adenosine decreased the concentration of protein and increased that of bicarbonate in the pancreatic juice stimulated by secretin. Adenosine, however, did not affect dopamine (3 micrograms i.a.)-stimulated pancreatic secretion. Adenosine (0.1-1.0 mg i.a.)-induced vasodilation was also reversed by the pretreatment with theophylline (0.3 mg i.a.). These results suggest the existence of adenosine 'R' receptors in the exocrine cells and the vasculature of the dog pancreas.

Metoclopramide enhances bethanechol-induced pancreatic exocrine secretion of the dog

The effects of metoclopramide on pancreatic exocrine secretion were investigated in the pentobarbitone-anaesthetized dog. All drugs were injected into the femoral vein. Metoclopramide (10-1000 micrograms/kg) did not change the resting rate of pancreatic secretion. Pancreatic secretion, induced by bethanechol (3 micrograms/kg), was dose-dependently enhanced by simultaneous injections of metoclopramide (10 and 30 micrograms/kg), but the protein and bicarbonate concentrations of the pancreatic juice were not affected. Secretions induced by secretin (0.1 units/kg) and dopamine (3 micrograms/kg) were not modified by metoclopramide at up to 30 micrograms/kg. A larger dose of metoclopramide (1000 micrograms/kg) suppressed dopamine-induced secretion to a lesser extent than the same dose of sulpiride. From these results, it is concluded that metoclopramide enhances secretory responses to cholinergic stimulations by peripherally sensitizing the muscarinic receptor-mediated exocrine process and this drug is a weaker antagonist of the dopamine D2 receptors than sulpiride.

Effects of synthesized phosphodiesterase inhibitors, DM 9278 and HWA 285, on pancreatic exocrine secretion of the dog

The effects of synthesized phosphodiesterase inhibitors, DM 9278 and HWA 285, on pancreatic exocrine secretion were investigated in isolated and blood-perfused canine pancreas. Close-arterial injections of DM 9278 (10-300 micrograms) and HWA 285 (300-3000 micrograms) caused dose-dependent increases in the flow rate of pancreatic juice and perfusion blood flow. Bicarbonate concentration in the pancreatic juice stimulated by DM 9278 (300 micrograms) or HWA 285 (3000 micrograms) was significantly higher than that in the resting pancreatic juice, although neither of the compounds affected protein concentrations in the pancreatic juice. In the secretory volume, 100 micrograms of DM 9278 corresponded roughly to 1000 micrograms of HWA 285, 0.1 units of secretin or 0.3 units of pancreozymin. These secretory and vascular effects were not modified by pretreatment with atropine or sulpiride. This study suggests that both DM 9278 and HWA 285 act directly on ductular cells of the pancreas and induce secretion of water and electrolytes.

Effects of isosorbide dinitrate on pancreatic exocrine secretion in the dog

The effects of isosorbide dinitrate (ISDN) on pancreatic exocrine secretion were investigated after intravenous administration in the whole animal and after close-arterial administration on the isolated and blood-perfused dog pancreas preparations. ISDN (10-100 micrograms/kg), injected into the femoral vein, caused a dose-dependent increase in flow rate of pancreatic juice and in protein concentration of the pancreatic juice. Close-arterial injections of ISDN (100-1000 micrograms) produced a dose-dependent increase in perfusion blood flow, flow rate of pancreatic juice and protein concentration of the pancreatic juice without affecting its bicarbonate concentration. These vascular and secretory effects were not modified by pretreatment with atropine. From these data, it is suggested that ISDN induces pancreatic enzyme secretion by acting directly on the acinar cells of the pancreas.

Effects of an indazole derivative, FKK, a novel bronchodilator, on the cardiovascular system in dogs

The cardiovascular effects of FKK (2,3-dihydro-7-methyl-9-phenyl-1H-pyrazolo [1,2-a]indazolium bromide) were compared with those of aminophylline and isoproterenol in anesthetized dogs. The doses of the three drugs used were sufficient to cause significant tracheal dilation in the anesthetized dogs. FKK (0.1-3.0 mg/kg, i.v.) slightly increased respiratory frequency, left ventricular (LV) dp/dt max and myocardial contractile force. A slight increase followed by a decrease was observed in systemic blood pressure and LV systolic pressure. The drug caused direct vasodilation in the coronary, mesenteric and femoral vasculatures, but had no effect on the renal vasculature. Similar results were obtained with aminophylline (0.3-30.0 mg/kg, i.v.) and isoproterenol (0.003-0.3 microgram/kg, i.v.), but their effects on the measured cardiac parameters were much more potent and long-lasting than those of FKK, when compared in doses producing a bronchodilation in similar magnitude. It is particularly pertinent that FKK (30 mg/kg, i.d., enough to cause marked bronchodilation), unlike aminophylline (30 mg/kg, i.d.), did not significantly influence the cardiovascular system.