A radiographic evaluation of facet sagittal angle in cervical spinal cord injury without major fracture or dislocation.

STUDY DESIGN: A retrospective radiographic study with a minimum 2-year follow-up. OBJECTIVE: To evaluate the relationships between the cervical articular facets' morphology and the incidence of traumatic cervical spinal cord injury (CSCI) without major fracture or dislocation. SETTING: Spinal Injuries Center, Japan. METHODS: This study included 113 patients with traumatic CSCI without major fracture or dislocation. Eighty-four healthy volunteers without neurological deficits or cervical cord pathology on magnetic resonance imaging (MRI) were defined as control subjects. We used a plain sagittal radiograph to measure the facet sagittal angles (FSA) at four cervical segments in all the CSCI patients and controls. We defined the FSA as the angle between the inferior margin of the superior cervical spinal body and the inferior articular process of the superior vertebra. RESULTS: Most frequent incidence of CSCI was seen at C3-4 segment (54%). With respect to CSCI at C3-4 segment, 55.7% of the subjects showed smallest FSA at C3-4 segment. CONCLUSION: Most of the traumatic CSCI at C3-4 segment showed raised cervical articular facets at C3-4 segment. On the basis of our results, we hypothesized that the raised cervical articular facets might have an important role in the etiology of traumatic CSCI. The cervical spinal cord at the C3-4 segment might receive the highest load during acute hyperextension of the cervical spine because of the C3-4 articular facets' morphology.

Subacute T1-low intensity area reflects neurological prognosis for patients with cervical spinal cord injury without major bone injury.

STUDY DESIGN: A retrospective imaging and clinical study. OBJECTIVES: To evaluate the relationship between magnetic resonance imaging (MRI) features and neurological prognosis in patients with traumatic cervical spinal cord injury (CSCI) without major bone injury. METHODS: A total of 72 patients with CSCI without major bone injury were treated conservatively in our hospital. MRI was performed for all patients at admission and 1 month following injury. We measured the antero-posterior and cranio-caudal diameter of intramedullary intensity changed area with T1-weighted images at the injured segment. Neurological evaluations were performed using the American Spinal Injury Association (ASIA) motor score and the modified Frankel grade at the time of admission and discharge. RESULTS: There was a significant relationship between the antero-posterior diameter ratio of the T1-weighted low-intensity area on MRI at the subacute stage and the ASIA motor score. The optimal threshold of the T1-weighted low-intensity diameter ratio for predicting the patient's ability to walk with or without assistance at discharge was determined to be 46%. Moreover, 96.8% of the patients with <50% T1-weighted low-intensity area recovered to walk with or without a cane at discharge. CONCLUSION: The T1-low intensity area may be an important predictive factor for the neurological recovery of CSCI without major bone injury.

The potential for functional recovery of upper extremity function following cervical spinal cord injury without major bone injury.

STUDY DESIGN: This was a retrospective observational study. OBJECTIVES: The objectives were to describe the prognosis of upper extremity function following cervical spinal cord injury (CSCI), and to identify prognostic factors for functional recovery. SETTING: Spinal Injuries Center, Japan. METHODS: Sixty patients with C3-4 CSCI without major bone injury participated in the study. Patients were treated nonsurgically and evaluated using the American Spinal Injury Association (ASIA) scales for the upper and lower extremities, their residual cervical motor functions, the modified Frankel grade and an upper extremity function scale. We compared the findings for the upper extremity function scale at 6 months with those for the residual cervical motor functions and modified Frankel grade obtained 3 days after injury. RESULTS: Most patients with CSCI who could flex their hip and knee from a supine position (95%) or who showed some active elbow extension (86%) 3 days after their injury could use a spoon at 6 months. We compared patients who used their fingers at 6 months to those who could not, and observed significant differences in age and ASIA scores for the upper and lower extremities obtained 3 days after injury. A strong correlation was observed between the initial motor scores and the extent of functional recovery at 6 months. CONCLUSION: Hip and knee flexion from the supine position and elbow extension 3 days after injury significantly predicted a positive prognosis for upper extremity function. Younger age and higher ASIA motor scores obtained 3 days after injury were factors associated with neurological recovery.

Outcome of decompression surgery for cervical spinal cord injury without bone and disc injury in patients with spinal cord compression: a multicenter prospective study.

STUDY DESIGN: A multicenter prospective study comparing the neurological outcome of patients treated by surgical intervention versus conservative treatment for cervical spinal cord injury (CSCI) without bone and disc injury. OBJECTIVE: To evaluate the neurological outcome of decompression surgery for CSCI without bone and disc injury in patients with spinal cord compression with incomplete paralysis (AIS B, C). SETTING: The Japan LHWO Spinal Injuries Center and the other 10 labor accident hospitals in Japan. METHODS: Thirty-four patients with AIS B, C and cervical spinal cord compression were classified into either a surgical treatment group or a conservative treatment group. The 34 patients enrolled were equally divided between the groups. Patients with AIS B, C and mild spinal compression were enrolled into another group. RESULTS: The neurological outcome of surgical treatment and conservative treatment for AIS B, C with spinal cord compression was found to be closely similar. In addition, the neurological outcome was also similar to that observed after conservative treatment for AIS B, C in patients presenting with mild spinal cord compression. CONCLUSIONS: Surgical treatment was not found to be superior to conservative treatment for CSCI patients without bone and disc injury suffering from spinal cord compression in the acute phase.

Epidermal growth factor receptor gene mutation, amplification and protein expression in malignant pleural mesothelioma.

Epidermal growth factor receptor (EGFR) is overexpressed in a variety of epithelial malignancies. In lung cancer cases, EGFR gene mutation at the kinase domain and EGFR gene amplification are reported to be predictors of the response to EGFR tyrosine kinase inhibitors. In malignant pleural mesothelioma (MPM), the role of EGFR is less clear. We studied EGFR gene mutation, amplification and protein expression in 25 Japanese patients with MPM. None had previously reported EGFR mutations detected by the TaqMan PCR assay. Using immunohistochemistry, 8/25 (32%) cases were positive for the EGFR protein. The cases of sarcomatous type and desmoplastic type were all negative. Fluorescence in situ hybridization analysis revealed three low polysomy cases and one high polysomy case. The low polysomy cases included one biphasic type and two epithelial types, and the high polysomy case was epithelial type. These four cases expressed EGFR protein. In MPM, EGFR seems to play a role in a limited subset of patients. To identify possible candidates for EGFR tyrosine kinase in inhibitor therapy, the information on the EGFR gene status may be valuable.

The role of substance P release in the lung with esophageal acid.

To investigate whether tachykinins are released in the airways by stimulating the esophagus, airway plasma extravasation induced by intraesophageal hydrochloric acid (HCl) in the presence or absence of the neutral endopeptidase (NEP) inhibitor phosphoramidon and the neurokinin-1-receptor antagonist FK888 was studied in anesthetized guinea pigs. Airway plasma extravasation also was studied in the presence of the NEP inhibitor in guinea pigs pretreated with capsaicin or bilateral vagotomy. Propranolol and atropine were used in all animals to block adrenergic and cholinergic nerve effects. Airway plasma leakage was evaluated by measuring extravasated Evans blue dye. One normal HCl infusion into the esophagus significantly increased plasma extravasation in the trachea. Phosphoramidon significantly potentiated plasma extravasation induced by HCl infusion into the esophagus in the trachea and main bronchi, and FK888 significantly inhibited extravasation in a dose-related manner. In capsaicin-treated animals, airway plasma extravasation was completely inhibited even in the presence of phosphoramidon. Tracheal plasma extravasation potentiated by phosphoramidon was significantly inhibited in the bilaterally vagotomized animals. These results suggest that locally acting substances are released by intraesophageal HCl stimulation that cause airway plasma extravasation. These substances are generated through activation of neural pathways, including some that traffic through the vagus nerves that link the esophagus or airways.

Dyspnoea and hyperventilation induced by synthetic progesterone chlorpromadinone acetate for the treatment of prostatic hypertrophy.

We describe a 74-year-old patient with dyspnoea and tachypnoea induced by chlorpromadinone acetate, a synthetic progesterone used to treat prostatic hyperplasia. The dyspnoea, tachypnoea and hypocapnia improved after discontinuing the chlorpromadinone acetate. It is important to recognize that synthetic progesterones can cause dyspnoea and hyperventilation.

Effect of intermittent cyclical treatment with etidronate disodium (HEBP) and calcium plus alphacalcidol in postmenopausal osteoporosis.

We evaluated intermittent cyclical treatment with etidronate disodium (HEBP) and calcium plus alphacalcidol in postmenopausal osteoporosis, with special reference to bone mineral density (BMD) and prevention of spinal fracture. The patients were 40 women, over 50 years of age, with lumbo-dorsal pain and low BMD (less than 0.70 g/cm(2)), measured by dual-energy X-ray absorptiometry (DXA). The patients were randomly assigned to two groups. The first group (HEBP) received 200 mg of HEBP per day for 2 weeks, followed by 2 g calcium lactate and 0.5 microg alphacalcidol per day for the next 10 weeks. This 12-week cycle was repeated eight times for 2 years. The second group (Ca. D) received 2 g calcium lactate and 0.5 microg alphacalcidol per day for 2 years. Lumbar BMD was measured before the treatment and every 6 months during the treatment until 24 months, and changes were evaluated. The number of fractured vertebrae was counted on X-ray films before treatment and at the final assessment. After 6 months of treatment, a significant and continuous increase in BMD was observed in the HEBP group. Moreover, the percentage of patients with new vertebral compression fractures in the HEBP group was one-tenth of that in the Ca. D group. These results suggest that intermittent cyclical treatment with HEBP and calcium plus alphacalcidol may be effective for increasing BMD and preventing fractures in postmenopausal osteoporosis.

Assessment of lung volumes in pulmonary emphysema using multidetector helical CT: comparison with pulmonary function tests.

The purpose of this study is to evaluate the usefulness of multidetector helical CT (MDCT) with three-dimensional (3D) postprocessing for assessing the lung volume at inspiration and expiration of the pulmonary emphysema and for comparing it with pulmonary function tests. Percentage lung volume at the threshold of -930, -900, -810, -790, and -770 at expiration showed good correlation with FEV1, FEV1/FVC, and DLCO/Va. Excellent correlation was observed between percentage lung volume at the threshold of -900 and FEV1/FVC. CT densitometry at expiration showed better correlation than that at inspiration with pulmonary function tests. MDCT with 3D technique is useful for assessing the severity of pulmonary emphysema.

[Prevalence of asthma in adults in Menda town rural-mountain area in Japan].

Several reports have suggested that the prevalence of asthma in adults is currently increasing. However, recent prevalence of asthma has not reported in Japan, especially in rural-mountain areas. To investigate the prevalence of asthma in adults in Japan, we conducted clinical epidemiological research on 5066 inhabitants of Menda town, in a rural-mountain area of Japan. The study population comprised 98.7% of adults in the town, including senior high school students whose age were more than 15 years old. The prevalence of asthma among adults was 3.6%. The ratio of prevalence in males to prevalence in females was 1.44. Peaks prevalences were observed in the age ranges of 15-19 and > 70 years old in males, and 15-19, 40-49 and > 70 years old in females.

Open carpal tunnel decompression in long-term haemodialysis patients [corrected].

This retrospective study assessed the treatment of 91 cases of carpal tunnel syndrome in long-term haemodialysis patients. One group of patients underwent an enlargement reconstruction of the flexor retinaculum with synovectomy and the other group was treated with a conventional carpal tunnel release. There were no major changes or differences between the outcomes of the two groups. However, there was an earlier functional recovery of grip strength and a lower recurrence rate in the enlargement plasty with synovectomy group.

Isolation of a lactose-binding protein with monocyte/macrophage chemotactic activity. Biological and physicochemical characteristics.

BACKGROUND: We established a T cell line, STO-5, which constitutively produced monocyte/macrophage chemotactic activity via human T cell lymphoma-leukemia-virus-induced transformation of normal human T cells. METHODS: We isolated and purified a lactose-binding protein, MCF-pl5-L (MW of about 50 kD, pl of about 5) from a conditioned medium of STO-5. By using highly purified MCF-pl5-L, its biological and physicochemical properties were elucidated in comparison with C5a and MCP-1. RESULTS: MCF-pl5-L exhibited an evident dose-dependent monocyte chemotactic activity (MCA). MCF-pl5-L had no or little affinity for heparin unlike chemokines such as MCP-1. We further found that MCF-pl5-L exhibited potent chemotactic activity not only for monocytes but also for alveolar macrophages. In contrast, C5a and MCP-1 failed to show evident chemotactic activity for alveolar macrophages though they did show MCA. MCF-pl5-L failed to exhibit evident eosinophil and neutrophil chemotactic activities, indicating its chemotactic activity is selective for monocytes/macrophages. Regarding the biological functions of MCF-pl5-L other than MCA and chemotactic activity for alveolar macrophages, we found that MCF-pl5-L but not C5a and MCP-1 could prolong the life span of alveolar macrophages, probably by inhibiting apoptosis of macrophages, and stimulate the production of TNF-alpha from macrophages. CONCLUSIONS: These results suggest that MCF-pl5-L plays a role as an immune modulator for monocytes/macrophages in the site.

Human bronchial intraepithelial T lymphocytes as a distinct T-cell subset: their long-term survival in SCID-Hu chimeras.

Intestinal intraepithelial T lymphocytes (i-IELs) show features different from those of conventional T cells and play specific roles in the mucosal immunity. To investigate whether human bronchial intraepithelial T lymphocytes (IELs) are a distinct entity, we examined T cells in human bronchial xenografts transplanted on mice with severe combined immune deficiency (SCID). We transplanted human bronchi subcutaneously into mice with SCID, resected the xenografts after various incubation periods (7-174 d), and examined them for CD3(+), CD4(+), CD8(+), and CD45(+) cells by immunohistochemistry. The number of CD3(+) cells in the lamina propria decreased significantly in the first month (from 308.7 +/- 60.2 to 70.9 +/- 49. 4/mm(2); P < 0.05), and xenografts more than 5 mo of age had scant T cells in the lamina propria (5.2 +/- 2.0/mm(2)). However, there was no significant difference between the number of CD3(+) IELs in freshly isolated bronchi and in xenografts maintained for more than 5 mo. In freshly isolated bronchi, the number of CD4(+) IELs was significantly lower than that of CD8(+) cells (2.35 +/- 0.62 versus 4.56 +/- 1.32/mm basement membrane; P < 0.01). After transplantation, the mean CD4-to-CD8 ratio of all xenografts was significantly higher than that of freshly isolated bronchi (5.2 +/- 0.9 versus 0.6 +/- 0.2; P < 0.005). The IELs were positive for CD45, which is specific for human leukocytes, and they were eliminated by irradiation before the transplantation. Almost all IELs (99.5%) in the xenografts expressed alphabeta T-cell receptor, and 35.8% of IELs expressed alpha(e)beta7 integrin. Bronchial epithelial cells in the xenografts expressed interleukin (IL)-7, stem cell factor, intercellular adhesion molecule (ICAM)-1, and human leukocyte antigen-DR (HLA-DR). We conclude that in the SCID-Hu chimera model, human bronchial IELs survive for more than 5 mo, unlike the T cells in the lamina propria, and we suggest that human bronchial IELs may be stimulated by bronchial epithelial cells expressing IL-7, stem cell factor, ICAM-1, and HLA-DR.

The role of cysteinyl leukotrienes in the pathogenesis of asthma: clinical study of leukotriene antagonist pranlukast for 1 year in moderate and severe asthma.

Clinical studies have shown that pranlukast (Ono Pharmaceutical Co., Osaka, Japan) is effective for mild and moderate asthma. However, it is not well known that pranlukast is also effective on moderate and severe persistent asthma in the long term. We studied the effect of pranlukast on moderate and severe asthmatics by evaluating the change of peak expiratory flow (PEF) and therapeutic scores for 1 year before and during pranlukast therapy. We gave pranlukast 225 mg twice daily orally to 25 patients who were receiving more than 400 micrograms/day beclomethasone inhalation and beta 2 stimulant inhalation with or without oral corticosteroid. Pranlukast increased PEF more than 10 L/min in 14 patients in the first 4 weeks. In these 14 patients, 10 patients continued to monitor PEF and kept asthma diaries for 1 year. We compared the data for 1 year before and during the pranlukast therapy. During the pranlukast therapy, PEF significantly increased, puffs of beta 2 stimulant inhalation significantly decreased. The incidence of oral corticosteroid rescue therapy reduced, and the mean daily dose of oral corticosteroid decreased; however, they were not statistically significant. During treatment with pranlukast, no side effect was observed. From these results, we suggest that pranlukast is effective for more than half of the moderate and severe persistent asthmatics, and that the effectiveness continues for more than 1 year.

Surgical treatments for orthopaedic complications in long-term haemodialysis patients--a review of 546 cases over the last 8 years.

We reviewed 546 operative cases in haemodialysis patients during the past 8 years between June 1990 and May 1998. The average age of the 257 male and the 289 female patients was 57.1 years. The average period of haemodialysis was 14 years and 4 months. We discussed the etiology, pathological focus, frequency, symptoms, problems and operative indications. Carpal tunnel syndrome occurred most frequently, occupying 289 cases. Short-term postoperative results were positive in the initial case within 6 months after the occurrence of the first symptoms. Because no effective method preventing recurrence existed, synovectomy was used as much as possible in the initial operation. Surgical treatment was used for amyloid arthropathy in 15 shoulders. It was effective in cases resistant to any conservative treatment. For the knee joint, the arthroscopic synovectomy was performed in 8 cases, and total knee replacement in 6 cases. The results of the total knee replacement cases were good. However, recurrences were observed in 40% of the synovectomy cases. In the hip joint, the curettage and bone grafting were performed in 7 hips of 6 patients. All bone grafts were consolidated and there was no case of postoperative pathological fracture. In some cases with destructive spondyloarthropathy, the vertebrae involved spontaneously fused without severe kyphotic deformity. A case with mild pain and without neurological deficit can be treated conservatively. A case with severe pain, instability, and myelopathy indicates operative measures must be taken. Attention must be paid for a possible collapse of the grafted bone after the cervical level two anterior fusion. Haemodialysis patients are vulnerable to infection. This diagnosis is difficult to distinguish due to the weakened state of the immune system. Rigorous attention is required to prevent and detect infection in cases using artificial joints or instrumentation. The treatment of bone and joint disturbances from dialysis-related amyloidosis has become surgical due to the advancement of dialysis control. However, it remains one of the more conservative treatments. Determining the cause and establishing a method of treatment are desired as early as possible.

Allergen exposure induces the expression of endothelial adhesion molecules in passively sensitized human bronchus: time course and the role of cytokines.

To study the mechanisms contributing to the recruitment of a selective leukocyte subset in allergic inflammation involving the airways as may occur in asthma, we examined whether allergic exposure induces the expression of cell adhesion molecules (CAMs) on the bronchial endothelium of passively sensitized human bronchi. Human bronchial tissue obtained from patients undergoing lung cancer surgery was passively sensitized with serum from patients with atopic asthma who were sensitive to house dust mite. We incubated the tissues for 30, 120, 240, and 480 min in the presence or absence of the dust mite allergen. The tissues were stained immunohistochemically for intercellular adhesion molecule 1 (ICAM-1), E-selectin, and vascular cell adhesion molecule 1 (VCAM-1). ICAM-1 was constitutively expressed in both the epithelium and endothelium in all tissues but after allergen stimulation significantly increased at 240 and 480 min. E-selectin expression also existed constitutively and increased significantly at 120 and 240 min with allergen exposure. The constitutive expression of VCAM-1 was less than that of ICAM-1 and E-selectin. Following allergen exposure, VCAM-1 expression increased significantly at 30, 120, 240, and 480 min, and at 480 min reached an almost 3.5-fold increase from baseline expression. The TNF-alpha level in the supernatants significantly increased at 120 min after allergen stimulation, and the interleukin (IL)-1beta level increased in 4 of 15 samples. We also examined the induction of CAMs by TNF-alpha, IL-1beta, and IL-4 on human bronchial tissue. TNF-alpha and IL-1beta increased the expression of ICAM-1, E-selectin, and VCAM-1, whereas IL-4 induced only that of VCAM-1. In addition, neutralizing antibody against TNF-alpha and IL-1beta partially blocked the upregulation of CAMs on passively sensitized bronchial tissue after allergen exposure. Thus, both an IgE-dependent allergic response and selected cytokines are able to upregulate endothelial CAMs in human bronchial tissue. These observations provide further evidence that leukocyte infiltration into the site of allergic inflammation as occurs in atopic asthma is in part regulated by the expression of ICAM-1, VCAM-1, and E-selectin.

Novel phosphodiesterase 4 inhibitor T-440 reverses and prevents human bronchial contraction induced by allergen.

To study the roles of phosphodiesterase (PDE) 4 in the human airways, we examined the effect of the novel PDE4 inhibitor T-440 in the isolated human bronchus. T-440 inhibited PDE4 extracted from human bronchial smooth muscle. IC50 values for the effect of T-440, rolipram (a PDE4 inhibitor) and theophylline on PDE4 activity of the bronchial tissues were 0.08 microM, 2 microM and > 100 microM, respectively. T-440 (10(-6) M to 10(-5) M) and aminophylline (3.3 x 10(-5) M) significantly reversed the 10(-5) M histamine-induced contraction, the efficacy of 10(-6) M T-440 being almost the same as that of 3.3 x 10(-5) M aminophylline. T-440 (10(-6) M to 10(-5) M) and aminophylline (3.3 x 10(-5) M) significantly reversed the 10(-4) M ACh-induced contraction. But their reversal effects on the ACh-induced contraction were weaker than those on the histamine-induced contraction. T-440 (10(-5) M) significantly reversed the contraction induced by allergen in passively sensitized bronchi. The efficacy of the reversal effect of T-440 (10(-5) M) was significantly higher than that of aminophylline (10(-5) M). T-440 and aminophylline significantly relaxed the basal tension, but pretreatment with T-440 or aminophylline did not significantly prevent histamine- or ACh-induced contraction. In contrast, both T-440 (10(-5) M) and aminophylline (3.3 x 10(-5) M) prevented the contraction induced by allergen, which suggests that PDE4 inhibitor inhibits the release of chemical mediators probably from bronchial mast cells in the allergic response. T-440 (10(-6) M to 10(-5) M) caused the accumulation of cAMP at the concentration that relaxed histamine-induced contraction. Thus selective PDE4 inhibitor is a candidate for the treatment of asthma.

Bronchial hyperreactivity in patients with familial amyloidotic polyneuropathy and autonomic neuropathy.

To investigate the role of autonomic regulation on airway reactivity, we performed bronchial inhalation tests of methacholine (MCh) and histamine (Hist) in Japanese patients with familial amyloidotic polyneuropathy (FAP) and autonomic neuropathy. First we examined the FEV1 and Raw in seven patients with FAP and in six normal subjects, then we administered aerosols of increasing concentrations of MCh (0.075 to 25 mg/ml) at about 5-min intervals via a nebulizer controlled by a dosimeter. We measured the FEV1 until either the concentration of MCh producing a 20% reduction from the basal value (PD20) or the maximal concentration was reached. Five of the seven patients with FAP showed bronchial hyperreactivity to MCh, and PD20 to MCh was significantly lower than that of the normal subjects (p < 0.01). Furthermore the PD20 tended to correlate inversely with the severity of autonomic neuropathy (p = 0.052). The bronchial hyperreactivity to MCh was completely blocked by pretreatment inhalation of ipratropium bromide, suggesting the muscarinic receptor-mediated mechanism. Of these five patients with hyperreactivity to MCh, three with low PD20 to MCh (< 50 units) did not respond to Hist, but two with high PD20 (> 50 units) to MCh did, suggesting different mechanisms of hyperreactivity to MCh and Hist in FAP. The PD20 to Hist significantly correlated inversely to the PD20 to MCh (p < 0.05). Histochemical examination revealed marked amyloid deposition in the vagus nerves and tracheal wall in an autopsied patient with FAP and severe autonomic symptoms. These data suggest that patients with FAP and advanced autonomic neuropathy have bronchial hyperreactivity to MCh and/or Hist, probably because of denervation supersensitivity resulting from amyloid deposition in the peripheral autonomic nerves of the airways.

Esophageal stimulation by hydrochloric acid causes neurogenic inflammation in the airways in guinea pigs.

To investigate whether tachykinins are released in the airways in response to stimulation of the esophagus, we studied the airway plasma extravasation induced by intraesophageal HCl in the presence or absence of neutral endopeptidase inhibitor phosphoramidon and NK1-receptor antagonist FK-888 in anesthetized guinea pigs. The airway plasma leakage was evaluated by measuring extravasated Evans blue dye in the animals pretreated with propranolol and atropine. Infusion of 1 N HCl into the esophagus significantly increased plasma extravasation in the trachea. Phosphoramidon significantly potentiated plasma extravasation in the trachea and main bronchi, whereas FK-888 significantly inhibited that extravasation in a dose-related manner. In the capsaicin-treated animals, airway plasma extravasation was completely inhibited even in the presence of phosphoramidon. Tracheal plasma extravasation potentiated by phosphoramidon was significantly inhibited in the bilateral vagotomized animals. These results suggest that 1) tachykinin-like substances are released to cause plasma extravasation in the airways as a result of intraesophageal HCl stimulation and 2) there are neural pathways communicating between the esophagus and airways, including the vagus nerve.

Evidence that allergen-induced contraction of guinea pig bronchi is mediated in part by the release of tachykinins.

To study the role of tachykinins in allergic responses in the airways of guinea pigs sensitized to ovalbumin (OVA), we examined the bronchial contractile response to allergen in the presence or absence of the tachykinin antagonist FK224 in vitro. Because neutral endopeptidase (NEP) effectively cleaves tachykinins, we incubated bronchial tissues with the NEP inhibitor phosphoramidon (10(-5) M) to maintain the activity of endogenously released tachykinins. Then we added 10(-5)% (10 microns/ml) OVA in the presence or absence of FK224 (10(-5) M). FK224 significantly inhibited OVA-induced contraction plateaued and began to relax, we added 10(-5) M phosphoramidon. In the tissue without FK224, phosphoramidon blocked the relaxation and enhanced the contraction. In contrast, in the tissues treated with FK224, phosphoramidon did not enhance the OVA-induced contraction. The enhancement of the contraction induced by phosphoramidon was not inhibited by the sodium channel blocker tetrodotoxin. These results suggest that (1) allergic response causes release of tachykinin-like substances to induce bronchial contraction in part, (2) these responses are blocked by tachykinin antagonist FK224 and (3) nerve conduction is not necessary for the release of tachykinin-like substances induced by allergic response in the guinea pig bronchus.