Rapid and semiquantitative analysis of HSP72 and HSC73 heat shock mRNAs by mimic RT-PCR

The amounts of mRNAs for 72 kDa (HSP72) and 73 kDa (HSC73) heat shock proteins were measured semiquantitatively with competitive polymerase chain reaction (PCR) techniques after reverse transcription (RT) using a heterologous DNA fragment (PCR mimic) as an internal standard. The changes of signal intensities of PCR products were well correlated with the amount of mRNA in rat brain measured as optical densities of Northern blot. Thus, an analysis with mimic RT-PCR technique provides a rapid, semiquantitative, and safe method to detect changes of HSP72 and HSC73 mRNAs after brain ischemia.

Amygdala N-methyl-D-aspartate receptors participate in the induction of long-term potentiation in the dentate gyrus in vivo

We investigated the effects of injection of N-methyl-D-aspartate (NMDA) receptor antagonists, 2-amino-5-phosphonovalerate (APV) and 7-chlorokynurenate (7-Cl-Kyn), into the basolateral amygdala (BLA) on long-term potentiation (LTP) in the medial perforant path-dentate gyrus granule cell synapses of anesthetized rats. Injection of APV or 7-Cl-Kyn into the ipsilateral BLA did not affect the baseline synaptic responses, but significantly attenuated the dentate gyrus LTP induced by tetanic stimulation. Injection of APV into the contralateral BLA did not affect the induction of LTP. When APV was injected after tetanic stimulation, it did not affect the maintenance phase of LTP. These results suggest that NMDA receptors in the ipsilateral BLA partly participate in the induction of LTP in the dentate gyrus in vivo.

CT scanning of bronchioloalveolar carcinoma: specific appearances

We reviewed CT scans in 38 cases with pathologically proved bronchioloalveolar carcinoma. CT revealed three CT patterns: solitary, pneumonic and diffuse forms. The solitary pattern (22 patients) had a high percentage of air bronchograms (95%), pleural indentation (77%) and spiculation (68%). The pneumonia-like pattern (16 lesions in 10 patients) had air bronchograms in all cases (100%), low attenuation (88%) and protrusion of interlobar fissures (63%). The diffuse form (six patients) had 2 or 3 mm diffuse small nodules scattered throughout the entire lung. CT of bronchioloalveolar carcinoma revealed many findings and was useful in recognizing the tumor distribution and extent. We conclude that CT is helpful for the diagnosis and evaluation of bronchioloalveolar carcinoma.

Fluid and protein secretion by the submandibular glands of weanling rats in response to cholinergic and peptidergic agonists at various doses

Fluid and protein secretion by the submandibular glands of 25-day-old rats were examined and compared in response to three cholinergic and four peptidergic sialogogues at various doses. All cholinergic and peptidergic agonists used were potent sialogogues for the submandibular glands of the weanling rats over the wide range of doses used. The cholinergic agonists, bethanechol and methacholine and the peptidergic agonists, substance P, substance PTyr8 and eledoisin-related peptide used intravenously, acted similarly to each other on the submandibular glands of the rats, late in the natural weaning period, but carbachol and physalaemin had slightly different effects. Of the peptidergic agonists, physalaemin was the most potent sialogogue among four tachykinins tested at the low dose. The types of protein secreted by the submandibular glands of the weanling rats in response to all sialogogues used here were typical of the beta-type. These results indicate that all agonists used could mainly stimulate the acinar cells of the submandibular glands of the weanling rats which have already fully developed functionally at this time.

Cytosolic Ca2+ dynamics in hamster ascending thin limb of Henle's loop

Intracellular calcium plays an important role in the regulation of Cl- reabsorption in the ascending thin limb of Henle's loop (ATL). To elucidate the cytosolic Ca2+ dynamics in the ATL, intracellular Ca2+ concentration activity ([Ca2+]i) was measured in the in vitro microperfused hamster ATL using fura 2. Basal [Ca2+]i was 89.1 +/- 7.3 nM (n = 9 tubules). Removal of Ca2+ from the peritubular solution decreased [Ca2+]i from 89.1 +/- 7.3 to 64.1 +/- 7.1 nM in 2 min (n = 9, P < 0.05), whereas [Ca2+]i did not change after removal of Ca2+ from the luminal solution. Addition of 1 mM NaCN to the bath increased [Ca2+]i. This effect was completely abolished by the elimination of ambient Ca2+. Trifluoperazine and N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7) in the bath reversibly increased [Ca2+]i, whereas addition of 1 mM ouabain to the bath decreased [Ca2+]i. Rates of changes in [Ca2+]i after removal and replacement of basolateral Ca2+ were not affected by removal of Na+, K+, or Cl- from the bath, whereas nicardipine decreased these parameters. Increasing bath K+ from 5 to 100 mM decreased [Ca2+]i from 69.3 +/- 5.8 to 50.8 +/- 5.0 nM in 1 min (n = 6, P < 0.05). Subsequent reduction of K+ from 100 to 5 mM increased [Ca2+]i to 174.0 +/- 30.8 nM in 1 min, followed by a gradual decrease in [Ca2+]i to a steady-state level of 74.2 +/- 8.0 nM in 2 min. Changes in basolateral K+ concentration did not affect [Ca2+]i in the absence of ambient Ca2+.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential effects of microtubule inhibitors on axonal branching and elongation of cultured rat hippocampal neurons

We investigated the effects of microtubule inhibitors, taxol and colchicine, on the axonal branching and elongation in cultured rat hippocampal neurons. Taxol (50 nM) did not affect the morphology of neurons cultured under the control conditions, but significantly reduced the axonal branching stimulated by basic fibroblast growth factor. The axonal elongation stimulated by astrocyte-conditioned medium was not affected by the same concentration of taxol. Colchicine (10 nM) showed similar effects as taxol. These results suggest that microtubules play more important roles in axonal branching than in axonal elongation.

Establishment of a new human cell line, LI90, exhibiting characteristics of hepatic Ito (fat-storing) cells

BACKGROUND

Thus far, human hepatic Ito (fat-storing) cell lines have not been established. Therefore, functional characteristics of Ito cells have not been fully investigated.

EXPERIMENTAL DESIGN

We established a new cell line, LI90, that exhibited characteristics compatible with those of Ito cells from a human hepatic mesenchymal tumor. LI90 cells were examined with phase-contrast microscopy, immunohistochemistry, and cytogenetics, and their vitamin A-storing activity was analyzed. To obtain a marker specific for Ito cells for immunohistochemical analyses, we raised mAb against LI90 cells and clarified the molecular nature of the Ag recognized with the new Ab using an expression cloning approach.

RESULTS

LI90 cells showed polygonal shape and had well developed alpha-smooth muscle actin filaments in their cytoplasm. In an overconfluent culture condition, LI90 cells aggregated to form a typical hills-and-valleys structure, LI90 cells produced various connective tissue components, such as collagen types I, III, IV, V, and VI, laminin, and fibronectin. In culture media containing vitamin A, LI90 cells formed many fat droplets in their cytoplasm, and fluorescence characteristic of vitamin A was observed in the droplets. By immunizing mice with LI90 cells, three separate mAb specifically reacting with Ito cells in human liver sections were established, and the Ag recognized with all three Ab were identified as extracellular matrix tenascin.

CONCLUSIONS

The above-described morphologic and functional characteristics, including vitamin A-storage and biosynthesis of tenascin, are compatible with those of Ito cells. Therefore, LI90 cells will be useful for in vitro studies of functions of human Ito cells.

Effect of dexamethasone on plasma free dopamine: dopaminergic modulation in hypertensive patients

To investigate the peripheral dopaminergic modulation in the pathogenesis of human hypertension, we examined the responses of plasma free dopamine (DA) to dexamethasone (Dx) administration, which is suggested to activate dopaminergic activity. We administered Dx 2 mg intravenously to patients with primary aldosteronism (PA), essential hypertension (EH), and normotensive controls (NT). Plasma free DA was increased significantly in all groups and the responses were more remarkable in PA than in EH and NT. Plasma epinephrine (E) showed a gradual increase while plasma norepinephrine (NE) tended to decrease in all groups. The responses of both plasma DA and E were completely blocked by 250 mg of alpha-methyl-p-tyrosine, a tyrosine hydroxylase (TH) inhibitor, suggesting that Dx may stimulate peripheral dopaminergic activity by increasing catecholamine synthesizing enzyme (probably TH) activities. These data suggest that DA itself plays an inherent role in the sympathoadrenal regulation rather than only as a precursor of NE and that dopaminergic hyperresponses may be involved in the pathophysiology of PA.

Apoptosis of mouse pancreatic acinar cells after duct ligation

It has been established that pancreatic exocrine acinar cells disappear after pancreatic duct obstruction. This study aimed to examine the relationship between the disappearance of the acinar cells and apoptosis after pancreatic duct ligation of the splenic lobe in dd-mice, six weeks of age. In some mice, the ligature was removed after two or three days. In addition to general light and electron microscopic examinations on the pancreatic tissues, paraffin sections stained with the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) method were observed to detect nuclear DNA fragmentation. Pancreatic acinar cells underwent apoptosis initiated with nuclear DNA damages three days after duct ligation and were completely deleted by seven days. Due to the elevation of the intraluminal pressure, the acinar cells showed interrupted secretion of their zymogen granules and disorganization of their rough endoplasmic reticulum, causing the cessation of granule formation before apoptosis started. These cytoplasmic changes prior to apoptosis are reversible, as observed after removal of the ligation. Apoptosis of the acinar cells was indentified by TUNEL-labeling of the nuclei, the condensation and margination of nuclear chromatin, and round fragmentation of cell bodies, all irreversible changes. Apoptosis of acinar cells seemed to stimulate the proliferation of duct cells, which comprised the main cell components in the exocrine pancreas after the disappearance of acinar cells.

Effects of isotonic saline loading on renal tubular and neurogenic dopamine release in conscious rabbits

1. This study was designed to investigate the effects of isotonic saline loading on renal tubular and neurogenic dopamine (DA) in conscious rabbits. 2. Isotonic saline loading did not affect mean arterial pressure, heart rate or renal blood flow but markedly increased urine volume, sodium excretion and DA excretion. 3. Renal DA spillover was not affected by venous emptying, while renal noradrenaline (NA) spillover tended to decrease during saline loading. The ratio of % renal DA spillover to % renal NA spillover increased to 2.3 +/- 0.6 (P < 0.05) 3 h after saline loading. 4. Isotonic saline loading increased renal tubular DA production but had little effect on neurogenic DA release.

Renal dopamine spillover rate using 3H-dopamine radiotracer technique as an index of renal dopaminergic nerve activity

Renal and total dopamine (DA) spillover rates at rest were measured in 25 conscious rabbits with chronically implanted renal vein catheters. Renal DA spillover rate was calculated from veno-arterial difference in plasma free DA concentrations across the kidney corrected by the fractional extraction of infused 3H-DA. Plasma free DA concentrations were 11.0 +/- 2.7 pg/ml in the artery and 14.3 +/- 3.6 in the renal vein. Renal and total DA spillover rates were 0.51 +/- 0.08, 2.61 +/- 0.30 ng/min, respectively, both of which were significantly (p < 0.001) lower than the respective norepinephrine (NE) spillover rates (renal: 16.3 +/- 1.4, total: 39.6 +/- 1.7). The fractional extraction of 3H-DA across the kidney (55 +/- 3%) and the total DA clearance (285 +/- 31 ml/min) were both significantly (p < 0.05) higher than that of 3H-NE (45 +/- 3) and the total NE clearance (198 +/- 9), respectively. The ratio of renal to the total spillover rate of DA (0.23 +/- 0.05) was significantly (p < 0.05) lower than that of NE (0.41 +/- 0.04). These results demonstrate that DA is released into plasma within the kidney and suggest that the measurement of renal DA spillover rate using 3H-DA radiotracer technique is useful to detect resting renal dopaminergic nerve activity.

Genomic structure of the mouse A-type lamin gene locus encoding somatic and germ cell-specific lamins

Mouse A-type lamin genes were isolated. Structural analyses revealed that all the three known mouse A-type lamins (A, C and C2) were coded in a single genomic locus in a 22 kilobase DNA segment. The three lamins were coded in 12, 10 and 10 exons for A, C and C2, respectively, and shared 8 exons among them. Primer extension analyses identified possible transcription start sites for both A/C and C2 genes suggesting that the locus is under the control of two separate promoters, that is a somatic cell-acting promoter (for A and C) and a testis-specific promoter (for C2) which resides in the first intron of the A/C gene. Sequence characteristics of the possible promoter regions are discussed. Divergence of the two somatic cell-type lamins (A and C) is formally accounted for by differential selection of poly(A) sites together with lamin A-specific splicing.

Molecular cloning of a fish gene encoding a novel seven-transmembrane receptor related distantly to catecholamine, histamine, and serotonin receptors

A genomic DNA fragment encoding a G protein-coupled seven-transmembrane receptor was isolated from Medaka fish, Oryzias latipes. The encoded protein is similar in sequence to other receptors including catecholamine, histamine and serotonin receptors. However, the similarity is much lower than those among members of these receptor subfamilies, thus suggesting this seven-transmembrane receptor to be an orphan receptor whose ligand has not yet been identified. Genomic Southern blot analysis suggested that the fish genome contains additional receptor genes related to the isolated gene, indicating that this novel receptor, possibly with its related receptors, might constitute a novel subfamily of the seven-transmembrane receptor superfamily.

[Antegrade or retrograde blood cardioplegic method: comparison of postsurgical right ventricular function and conduction disturbances]

This study was undertaken to compare postsurgical right ventricular function and the occurrence of conduction disturbances after employing cold blood antegrade or retrograde cardioplegia during open heart surgery. Thirty-four patients were divided into AC (antegrade) and RC (retrograde) groups for the difference of route for delivery of cardioplegic solutions. Preoperative evaluation of cardiac and respiratory function revealed to be equal characteristics between the groups. Postoperatively, A-aDO2 and respiratory index (RI) as functional parameters of oxygenation capacity, LVSWI, RVSWI, dosage of dopamine and conduction disturbances were monitored at 0, 3, 6, 12 hours after termination of cardiopulmonary bypass and at extubation period. Although the recovery of respiratory function and left ventricular function were similar in both groups, temporal suppression of right ventricular function was indicated in RC group during early period after surgery, and then recovered to the same values of AC group within 3 hours. In RC group, several type of conduction disturbances were detected in 28 per cent of patients. But none of the persistent conduction disturbances were remained in all patients. We suggest retrograde coronary sinus perfusion may emerge as a valuable alternative to antegrade methods for delivery of cardioplegia.

Long-term effects of radioiodine on thyrotrophin receptor antibodies in Graves' disease

OBJECTIVE

Graves' disease is recognized as an organ-specific autoimmune disorder caused by the presence of TSH receptor antibodies. The long-term effects of 131I treatment for Graves' disease on TSH receptor antibodies have not previously been studied. We have measured the TSH-binding inhibitory immunoglobulin (TBII) index and thyroid stimulating antibody (TSAb) activity in patients with Graves' disease following treatment with 131I.

DESIGN

A retrospective study.

PATIENTS

Two hundred and twenty-five patients with Graves' disease who were treated with 131I 1-13 years earlier were studied (1 year: 27 patients; 2-5 years: 42 patients; 6-9 years: 79 patients; 10-13 years: 77 patients).

MEASUREMENTS

The TBII index was measured as the percentage 125I-TSH bound to pig thyroid membranes and TSAb activity as the amount of cAMP produced by cultured FRTL-5 cells.

RESULTS

TBII was detected in 78% of patients prior to 131I administration. Following 131I administration, the incidence of positive TBII was 85% at the end of the first year decreasing to 40, 19, and 17% at 2-5, 6-9 and 10-13 years, respectively. The frequency of a positive TSAb was 74% at the end of the first year, and also decreased to 49, 27 and 29% at 2-5, 6-9 and 10-13 years, respectively. At more than 2 years after 131I therapy, the frequencies of hyperthyroidism in TBII and TSAb positive patients were 42% (19/45) and 30% (19/63), respectively, which were significantly higher than those in TBII and TSAb negative patients (8%: 12/153 and 8%:11/131, respectively). The frequency of hyperthyroidism after 131I treatment in patients with negative TBII before treatment (7%:2/29) was significantly lower than that (29%:30/102) in patients with positive TBII before treatment.

CONCLUSIONS

These results indicate that (1) the TBII index and TSAb activity decreased over a period of more than 2 years after 131I therapy for Graves' disease, and (2) the TBII index before treatment may influence the long-term outcome of 131I therapy.

Adrenomedullin in human brain, adrenal glands and tumor tissues of pheochromocytoma, ganglioneuroblastoma and neuroblastoma

Adrenomedullin is a potent vasodilator peptide that was isolated from human pheochromocytoma. But the presence of adrenomedullin in the brain has not been clarified. We studied the presence of adrenomedullin in the human brain obtained at autopsy from 6 subjects by radioimmunoassay, as well as in the human adrenal glands and tumor tissues of pheochromocytoma, ganglioneuroblastoma and neuroblastoma. Immunoreactive adrenomedullin was detected in every region of human brain examined (0.26-1.4 pmol/g wet weight) with the highest concentrations found in thalamus (1.40 +/- 0.39 pmol/g wet weight, mean +/- SEM) and hypothalamus (1.28 +/- 0.48 pmol/g wet weight). Reverse phase high performance liquid chromatography showed that the immunoreactive adrenomedullin in the human brain was eluted in the position of synthetic human adrenomedullin 1-52. High concentrations of immunoreactive adrenomedullin were found in human adrenal glands (12.6 +/- 1.0 pmol/g wet weight, n = 7), pheochromocytoma (4.5 +/- 1.5 pmol/g wet weight, n = 11), ganglioneuroblastoma (2.0 +/- 1.3 pmol/g wet weight, n = 4) and neuroblastoma (0.55 +/- 0.21 pmol/g wet weight, n = 3). The present study has shown that adrenomedullin is present in the human brain in high concentrations, suggesting that adrenomedullin acts as a neurotransmitter, neuromodulator or neurohormone in man.

[Effect of 5-FU on the utilization of purine and pyrimidine by human gastric cancer cells (KATO III)]

Effect of utilization of purine and pyrimidine in the culture medium by human gastric cancer cells (KATO III) was evaluated. Nucleosides mixture solution (OG-VI), consisting of inosine, guanosine 5' monophosphate (5'GMP), cytidine, uridine and thymidine (4: 4: 4: 3: 1 in molar ratio) was used and their levels in the culture medium was measured by HPLC after 3 day culture. Purine, inosine and 5' GMP, in the medium almost decreased and purine base, xanthine and hypoxanthine levels increased, but changes in pyrimidine level were minimal. 5-FU decreased purine and increased pyrimidine consumption. Addition of nucleosides mixture did not enhance the cellular proliferation, but inhibited growth when given in higher concentrations. Nucleoside mixture solution enhanced growth inhibition by 5-FU and it is a potential biochemical modulator of 5-FU metabolism in human cancer cells.

Variance of age at onset in a Japanese family with amyotrophic lateral sclerosis associated with a novel Cu/Zn superoxide dismutase mutation

Although about 5 to 10% of amyotrophic lateral sclerosis (ALS) cases are familial, the pathophysiology of ALS remains unknown. A new point mutation in exon 4 of the Cu/Zn superoxide dismutase (SOD) gene, resulting in an amino acid substitution of leucine84 by valine (L84V), in a Japanese patient with familial ALS (FALS) was identified. This L84V substitution was not observed in 57 normal Japanese control subjects. The enzymatic activities of Cu/Zn SOD of skin fibroblasts were significantly reduced to 75% of the control level in the affected patient. The progression of the disease with this mutation is very rapid, but the age at onset varies with sex or generation within a family.

The mechanism responsible for hypertension in a patient with Guillain-Barré syndrome

We report a case of hypertension associated with Guillain-Barré syndrome. In this case, the circadian variation of blood pressure was interrupted. Examination of neurohumoral factors revealed a hyperactive sympathetic nervous system and an increase in plasma renin activity. Clonidine, which acts centrally to inhibit sympathetic outflow, did not suppress serum norepinephrine or epinephrine. These observations suggest that autonomous hyperactivity of the efferent pathway of the sympathetic nervous system may cause the sustained hypertension throughout the day in this case.

High-frequency stimulation of the basolateral amygdala facilitates the induction of long-term potentiation in the dentate gyrus in vivo

We investigated the effect of high-frequency stimulation of the basolateral amygdala (BLA) on the induction of long-term potentiation (LTP) in the medial perforant path (PP)-dentate gyrus (DG) synapses of anesthetized rats. A conditioning stimulation (100 pulses at 100 Hz) of the ipsilateral BLA did not change the DG synaptic potential. However, when the BLA conditioning stimulation was applied at the same time as a weak tetanic stimulation of PP (20 pulses at 20 Hz) which alone did not induce LTP, robust DG LTP was induced. Simultaneous application of contralateral BLA stimulation and PP weak tetanus did not induce LTP. Moreover, the ipsilateral BLA stimulation enhanced the magnitude of LTP induced by a moderate tetanic stimulation of PP (30 pulses at 60 Hz), but did not further enhance the LTP induced by a strong tetanic stimulation of PP (100 pulses at 100 Hz). These results suggest that the ipsilateral BLA neurons modulate the induction of DG LTP in vivo.

Participation of CR1 (CD35), CR3 (CD11b/CD18) and CR4 (CD11c/CD18) in membranoproliferative glomerulonephritis type I

Intraglomerular expression of complement receptors (CR) was investigated chronologically in 22 repeatedly biopsied patients with membranoproliferative glomerulonephritis (MPGN) type I by indirect immunoperoxidase staining using MoAbs. Patients were divided into two groups based on whether intraglomerular C3c deposition was decreased at the second biopsy (2nd Bx) (group A, n = 12), or not (group B, n = 10). At the first biopsy (1st Bx), the severity of glomerular injury and the degree of glomerular C3c deposition were compatible between the two groups. Four patterns of CR1 (CD35) expression on podocytes were recognized: normal; generally decreased; focally/segmentally lost; and completely lost. The numbers of CR3 (CD11b/CD18)- and CR4 (CD11c/CD18)-positive cells per glomerular cross-section were counted. At the 1st Bx, no significant difference was found in the number of CR3+ or CR4+ cells between the two groups. At the 2nd Bx, the numbers of both the CR3+ and CR4+ cells were significantly decreased only in group A (P < 0.01). The numbers of CR3+ and CR4+ cells were significantly higher in cases with moderate or marked C3c deposits than in those with no or mild C3c deposits. The intensity of CR1 expression in group B was less than that in group A at both the 1st and 2nd Bx (1st, P < 0.05; 2nd, P < 0.01), and chronological improvement of CR1 expression was observed only in group A. The severity of glomerular injury was increased only in group B (P < 0.01), and was associated with persistent massive proteinuria and hypocomplementaemia. Our results suggest that, in cases with an adverse outcome, a more severe defect of CR1 initially exists and the expression of CR1 is not recoverable chronologically. This irreversible decrease or loss of CR1 may partly contribute to the continuous C3c deposition and intraglomerular infiltration of CR3+ and CR4+ cells.

A simple and rapid method for preliminary evaluation of in vivo efficacy of anti-HIV compounds in mice

In vivo efficacy of anti-HIV compounds is affected by various factors such as bioavailability, metabolism, clearance, and toxicity. Here we report a simple and rapid method that might be useful for preliminary evaluation of in vivo efficacy of anti-HIV compounds. MT-4 cells carrying proviral HTLV-1 were infected with HIV-1 in vitro and injected into the peritoneal cavity of SCID mice or BALB/c mice. Inoculated cells survive for 1-2 days, and support one to two cycles of viral replication which can be monitored by RT activity or p24 content in the supernatants of peritoneal wash fluids. Test compounds were administered either orally or subcutaneously. AZT, DDC and DDI, the nucleoside-type RT inhibitors currently in clinical use, all showed potent anti-HIV-1 activities in this mouse/MT-4 assay. HEPT (E-EBUdM), a non-nucleoside RT inhibitor, also showed potent anti-HIV-1 activity in vivo, whereas TIBO (R82913), another non-nucleoside RT inhibitor, was less active. In protease inhibitors KNI-272 and Ro 31-8959 showed good in vivo activities, while KNI-144, a compound closely related to KNI-272, showed poor in vivo activity. This mouse/MT-4 assay, although having a number of shortcomings as an animal model for HIV-1 infection, may be of some practical utility for preliminary evaluation of in vivo efficacy of potential anti-HIV compounds.

[Precision and problems in interpretation of acoustic rhinometry in cases of nasal mass lesion]

Precision and problems in interpretation of results obtained by acoustic rhinometry (AR) in cases of mass lesion in the nasal cavity were evaluated with two models, a simple tubal model and a model based on the cast of a cadaver's nasal cavity (cadaver model), and with a human subject. A simple tubal model of 2 cm inside diameter was used. Spherical claies with volumes of 1, 2, 3, and 3.5 cm3, located at same point in the tube, were measured by AR, and a high correlation was found between the clay volume calculated by AR and the real volume of the clay (r = 0.996). But the peak of decrease on the acoustic curve caused by clay was seen a bit posterior to the point where it was actually located. In the entire segment posterior to the peak on the acoustic curve, the value of the area was shown to be smaller than the value of the control. And the large the volume of clay, the greater the degree of decrease in this segment. In the study using the cadaver model, a pill (0.3 cm3) was put at nine sites in the nasal cavity, and AR was performed in each case. The results were compared with the control curve. The decrease in the area on the acoustic curve corresponding to the site of pill placement was recognized, as in the simple tubal model study, and a decrease in the area in the posterior segment of the acoustic curve was also observed.(ABSTRACT TRUNCATED AT 250 WORDS)