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K Munakata

Publications and source records attributed to K Munakata.

At least 19 recordsLinked to original sources
PubMed2002

Histologic criteria for the diagnosis of allied diseases of Hirschsprung's disease in adults.

A few reports in the literature have discussed the histologic criteria for the diagnosis of allied diseases of Hirschsprung's disease in adults, and studies report that intestinal neuronal dysplasia (IND) in adults may develop from IND in infants. The aim of this study was to examine the differences between the histological findings of IND in infants and those in adults, and to assess whether allied diseases of Hirschsprung's disease (HD) in adults should be considered as congenital or acquired diseases. For these purposes, we studied nine adult patients with severe constipation, and an adult patient with acute intestinal obstruction. We routinely examined the patients using barium enema, anorectal manometry and rectal mucosal biopsy. However, in patients suspected of allied diseases, we carried out full-thickness rectal biopsies. In seven operated cases, we also examined resected intestines. The tissue samples were examined using AChE-staining, NADPH-diaphorase staining, HE-staining, and silver impregnation. Histologically, we diagnosed two males as having HD, two males as having IND, five patients (two males and three females) as having hypoganglionosis, and one female as having a degeneration of the intramural plexus. The following conclusions were drawn: 1) Inflammations such as ulcerative colitis or ischemic colitis may cause IND TYPE B in adults whose histological findings are similar to those generally seen in infants; 2) It is suggested that IND is closely related to hypoganglionosis; 3) In hypoganglionosis, a patient with findings of elevated AChE-positive nerve fibers in the mucosa and AChE-positive nerve fibers in an arterial wall may belong to a subtype of IND; 4) Most of the allied diseases of HD in adults may occur as an acquired disease, not as a congenital disease.

Adult↗
PubMed2001

Resting ultrasonic tissue characterization and dobutamine stress echocardiography for prediction of functional recovery in chronic left ventricular ischemic dysfunction.

This study was designed to assess the diagnostic accuracy of the percentage of resting systolic wall thickening (WT), dobutamine stress echocardiography (DSE), resting cyclic variation of integrated backscatter (IBS-CV), and low-dose dobutamine stress IBS-CV (DSE-IB) for the prediction of regional function recovery (RFR) in patients with chronic left ventricular (LV) ischemic dysfunction. The study also evaluated whether or not global LV function affected the diagnostic accuracy. All studies were conducted before percutaneous transluminal coronary angioplasty (PTCA) and RFR was assessed after PTCA (mean interval, 10 months) in 30 patients with chronic LV ischemic dysfunction. Patients were divided into 2 groups according to the LV ejection fraction (LVEF): group A, LVEF<40%, n=14; group B, LVEF> or =40%, n=16. Of a total of 480 segments, 37 initially demonstrating akinetic wall motion before PTCA were analyzed. The wall motion of 24 of the 37 segments improved on visual analysis after PTCA. In the prediction of RFR, resting WT, DSE, resting IBS-CV and DSE-IB had sensitivities of 79%, 79%, 92% and 62%, and specificities of 54%, 84%, 83% and 69%, respectively. In particular, the resting IBS-CV in group A, as well as DSE, was an excellent predictor of RFR (sensitivity, 100%; specificity, 86%; vs sensitivity, 82%; specificity, 78%; respectively). Therefore, both resting IBS-CV and DSE are useful predictors for RFR in patients with chronic LV ischemic dysfunction.

Aged↗
PubMed2000

Simultaneous assessment of Tc-99m-sestamibi and I-123-BMIPP myocardial distribution in patients with myocardial infarction: evaluation of left ventricular function with ECG-gated myocardial SPECT.

123I-labeled 15-(p-iodophenyl)-3R,S-methyl pentadecanoic acid (BMIPP) is a branched-chain free fatty acid that is used to evaluate various cardiac diseases. The aim of the present study was to investigate the relationship between myocardial perfusion (99mTc-sestamibi) and BMIPP uptake, and to correlate perfusion and metabolic alterations with regional left ventricular dysfunction in patients with myocardial infarction (MI). ECG-gated dual-isotope myocardial SPECT was performed on 130 patients with MI with sestamibi (555 MBq) and BMIPP (148 MBq). The patients were classified into 3 groups according to PTCA therapy and the interval between the onset of infarction and RI injection (OR time). Group A (n = 56) included patients whose OR time was less than one month and who had undergone successful PTCA, Group B (n = 36) had OR times of less than one month and had conservative medical therapy, and Group C (n = 38) had OR times of over one month. The severity scores of the dual-isotope images were calculated from the defect scores in 9 segments. From the ECG-gated SPECT data with sestamibi, the left ventricular ejection fraction (LVEF; %) and regional wall motion were determined automatically using the QGS program LVEF obtained from gated SPECT correlated well with the severity scores for sestamibi and BMIPP (r = -0.68 and -0.76, respectively). The delta severity scores (BMIPP scores - sestamibi scores) of Group A were significantly higher than those of the other two groups (3.6 +/- 3.0 vs. 1.5 +/- 1.7 and 1.0 +/- 1.4, p < 0.001 ). The rate of dysfunctional segments with normal sestamihi distribution was significantly higher in Group A than in Group C (20.7% vs. 6.7%, p < 0.001). ECG-gated dual-isotope SPECT is useful since myocardial perfusion, fatty acid metabolism and left ventricular function can be analyzed during a single examination, so that this procedure has the potential to provide comprehensive information when evaluating patients with ischemic heart disease.

Adult↗
PubMed2000

A role of angiotensin-converting enzyme gene polymorphism in left ventricular remodeling after myocardial infarction.

BACKGROUND: Left ventricular remodeling (LVR) process is one of the important secondary sequele after acute myocardial infarction (AMI). However, little is known about the relationship between LVR and angiotensin converting enzyme (ACE) gene polymorphism as well as endothelial nitric oxide synthase (ecNOS) gene polymorphism. METHODS: Coronary angiography and left ventriculography were performed within 24 hours and 30+/-7 days after AMI onset. All consecutive 24 patients (57+/-6 years) had acute anterior MI with one vessel disease of left anterior descending artery and successful revascularization therapy during acute phase. Patients were divided into three groups according to the change of end-diastolic volume index (EDVI)(Delta EDVI = EDVI 1 month-EDVI within 24 hrs); LVR(+) (Delta EDVI>7.0 ml/m(2), n = 5), LVR (-)(Delta EDVI<-7.0 ml/m(2), n = 13), and LVR (+/-)(-7.0<Delta EDVI<7.0 ml/m(2), n = 6) groups. The polymorphisms of ACE and ecNOS gene were determined with PCR method after an extraction of genomic DNA from peripheral leukocytes. RESULTS: There were no significant difference among three groups as to baseline characteristics, including coronary risk factors, medications, serum CPKmax and patency of infarct-related artery. The incidence of DD genotype of ACE gene is significantly higher in LVR (+) than in the other two groups (0.60; 0; 0, respectively, chi(2) = 13.150, p<0.01). The incidence of D allele of ACE gene is also significantly higher in LVR (+) than in the other two groups (0.70; 0.17; 0.19, respectively, chi(2) = 10.221, p<0.01). Delta EDVI of DD genotype was significantly greater than in the other two groups (DD genotype = 30.1+/-18.1; ID genotype = -13.0+/-27.4; II genotype = -8.2+/-11.5 ml/m(2), respectively, p<0.05). There was no significant difference in ecNOS gene polymorphism among three groups. By stepwise regression analysis, the significant independent predictors of Delta EDVI were EDVI within 24 hrs and DD genotype (F = 16.88 and 8.641, respectively, p = 0.0024). CONCLUSION: These results showed that left ventricular dilatation is related to DD genotype of ACE gene after successful reperfusion therapy of anterior AMI. Thus, renin-angiotensin system may play an important role in left ventricular remodeling after AMI.

Aged↗
PubMed1999

Augmentation of vecuronium-induced neuromuscular block during sevoflurane anaesthesia: comparison with balanced anaesthesia using propofol or midazolam.

We have quantified the potentiating effects of 1.7% sevoflurane (n = 12) on vecuronium-induced neuromuscular block and compared the results with those obtained during balanced anaesthesia with propofol (n = 12) or midazolam (n = 12) in 36 patients. Neuromuscular function was monitored using an accelerograph and the train-of-four responses of the adductor pollicis muscle to ulnar nerve stimulation. Vecuronium 0.1 mg kg-1 was administered as an intubating dose, and maintenance doses of 0.02 mg kg-1 were administered on three occasions when T1/T0 had recovered to 25%. Thereafter, spontaneous recovery was monitored until complete. Times to 25% recovery of T1/T0 (DUR25) after an intubating dose of vecuronium did not differ between groups (mean 44.2 (SD 18.7) min for sevoflurane, 38.3 (7.5) min for propofol and 35.5 (9.5) min for midazolam). DUR25 values after each maintenance dose were 29.8 (9.5) min, 30.3 (10.4) min and 31.6 (10.7) min during sevoflurane anaesthesia, and were significantly longer than values for propofol (21.7 (6.0) min, 21.5 (5.8) min and 21.9 (5.8) min) and midazolam (20.0 (5.9) min, 19.3 (7.7) min and 19.8 (8.0) min) (P < 0.05) in each case). Recovery index25-75% and interval from T1/T0 = 25% to T4/T1 = 0.7 after the final dose of vecuronium were significantly prolonged by sevoflurane (28.3 (13.2) min and 42.7 (16.4) min) compared with propofol (17.6 (6.1) min and 26.6 (9.8) min) or midazolam (16.3 (9.4) min and 26.0 (10.2) min) (P < 0.05 in each case).

Adult↗
PubMed1999

Meiotically and mitotically stable inheritance of DNA hypomethylation induced by ddm1 mutation of Arabidopsis thaliana.

In contrast to mammalian epigenetic phenomena, where resetting of gene expression generally occurs in each generation, epigenetic states of plant genes are often stably transmitted through generations. The Arabidopsis mutation ddm1 causes a 70% reduction in genomic 5-methylcytosine level. We have previously shown that the ddm1 mutation results in an accumulation of a variety of developmental abnormalities by slowly inducing heritable changes in other loci. Each of the examined ddm1-induced developmental abnormalities is stably transmitted even when segregated from the potentiating ddm1 mutation. Here, the inheritance of DNA hypomethylation induced by ddm1 was examined in outcross progeny by HPLC and Southern analyses. The results indicate that (i) DDM1 gene function is not necessary during the gametophyte stage, (ii) ddm1 mutation is completely recessive, and (iii) remethylation of sequences hypomethylated by the ddm1 mutation is extremely slow or nonexistent even in wild-type DDM1 backgrounds. The stable transmission of DNA methylation status may be related to the meiotic heritability of the ddm1-induced developmental abnormalities.

Arabidopsis↗
PubMed1999

Left ventricular function at rest and during bicycle exercise in normal subjects: assessment by ECG-gated myocardial perfusion SPET with 99Tcm-tetrofosmin.

99Tcm-labelled myocardial perfusion tracers allow simultaneous assessment of myocardial perfusion and left ventricular function using ECG-gated SPET. The aim of this study was to evaluate left ventricular performance during exercise by means of ECG-gated myocardial perfusion SPET. After the administration of 99Tcm-tetrofosmin (555-740 MBq), eight healthy volunteers aged 27-49 years underwent ECG-gated myocardial perfusion SPET at rest and during supine submaximal exercise (75 and 125 W), for 3 min each. Using ECG-gated SPET data, left ventricular end-diastolic volume (LVEDV) demonstrated a biphasic response during exercise (from 106.4 +/- 17.5 to 119.9 +/- 19.9 to 108.1 +/- 19.2 ml). In contrast, left ventricular end-systolic volume decreased gradually and significantly during exercise (from 47.1 +/- 11.9 to 41.5 +/- 8.9 to 36.1 +/- 10.1 ml; P < 0.05), and left ventricular ejection fraction continued to increase at higher workloads (from 56.1 +/- 6.0 to 63.0 +/- 2.7 to 67.0 +/- 4.3; P < 0.01) despite a fall in LVEDV. There was a progressive increase in cardiac output during exercise, which reached a peak of 7.2 +/- 0.9 l.min-1. We conclude that ECG-gated myocardial perfusion SPET can assess left ventricular function during exercise and may provide useful information for the evaluation of patients with ischaemic heart disease.

Adult↗
PubMed1999

Correlation between atrial natriuretic peptide and baroreflex sensitivity in patients with congestive heart failure.

The aim of this study was to investigate the relationship between baroreflex sensitivity (BRS) and humoral factors in patients with congestive heart failure (CHF). BRS was assessed by the phenylephrine method in 16 patients with CHF and in 13 healthy controls. The CHF group was subdivided into 2 groups according to BRS (group A: <6 ms/mmHg, n=9; group B: > or =6 ms/mmHg, n=7). BRS was markedly depressed in CHF than in the controls (4.8+/-2.0 vs 8.3+/-3.6 ms/mmHg, p<0.01), and lower in group A than group B (3.3+/-1.3 vs 6.7+/-0.6 ms/mmHg, p<0.01). The plasma human atrial natriuretic peptide (h-ANP) level in group A was significantly higher than in group B (54.6+/-27.6 vs 18.0+/-7.4 pg/ml, p<0.01), and a significant inverse correlation was observed between plasma h-ANP and BRS (r=-0.635, p<0.01). However, there were no significant differences between the 2 groups in plasma catecholamine concentration, plasma renin activity and cardiac function by echocardiogram. These findings suggest that the elevation of endogenous ANP may also serve to compensate for impaired BRS in patients with CHF, in addition to its principal actions, such as diuresis and vasodilation.

Aged↗
PubMed1999

The role of alcohol dehydrogenase 2 and aldehyde dehydrogenase 2 genotypes in alcohol-induced vasospastic angina.

Alcohol ingestion often provokes attacks in patients with vasospastic angina. Type 2 aldehyde dehydrogenase (ALDH2) deficiency, which is based on a single point mutation (Glu487Lys) of the ALDH2 gene, is common in the Japanese population, but rare among the Caucasian population. We investigated how the genotype of ALDH2 affects the characteristics of alcohol-induced vasospastic angina. Ninety-one patients with vasospastic angina who had ingested alcohol daily or occasionally were studied. Patients had been diagnosed as vasospastic angina by a provocation test with an intracoronary injection of ergonovine or acetylcholine during coronary angiography. The Glu487Lys mutation was detected by allele specific PCR. We interviewed the patients to obtain information concerning the relationship between alcohol ingestion and anginal attacks. Alcohol ingestion induced attacks in 16 of 66 patients without the Glu487Lys mutation, 8 of 22 in heterozygotes, and 1 of 3 in mutant homozygotes. The intervals between alcohol ingestion and the onset of anginal attacks were shorter in homozygotes (0.17 hours) and heterozygotes (1.5+/-0.6 hours) for ALDH2*2 than in normal homozygotes for ALDH2*1 (5.4+/-0.6 hours). The amount of ethanol which induced attacks was significantly greater in normal homozygotes than in homozygotes (11 ml) and heterozygotes (42.5+/-7.1 ml) for ALDH2*2 (96.1+/-13.4 ml in normal patients). The frequency of anginal attacks induced by alcohol ingestion did not differ between ALDH deficient and normal homozygotes. In ALDH deficient patients, however, anginal attacks were induced by a smaller amount of alcohol immediately after its ingestion. Thus, the ALDH2 genotype modifies the characteristics of the anginal attacks as a co-factor for the induction of vasospastic angina after alcohol ingestion.

Alcohol Dehydrogenase↗
PubMed1999

[Myocardial distribution of iodine-123-iodophenyl-9-methyl-pentadecanoic acid (9MPA) in patients with acute myocardial infarction: comparison with regional wall motion obtained from technetium-99m-sestamibi gated SPECT].

123I-iodophenyl-9-methyl-pentadecanoic acid (9MPA) is a modified long-chain (15 carbons) fatty acid with a methyl branch on its 9 carbon location. Myocardial SPECT images (two sets, 10 min each) were obtained starting 10 min (early phase) and 50 min (delay phase) after the injection of 160 MBq 123I-9MPA at rest in 10 patients with acute myocardial infarction. The segmental myocardial uptake (% uptake) and clearance (% washout) from early to delay image were calculated by the SPECT data. ECG-gated myocardial SPECT with 99mTc-sestamibi was also performed and segmental left ventricular (LV) wall motion was evaluated using QGS (quantitative gated SPECT) program. The % uptake of LV segments with hypokinetic or akinetic wall motion were significantly lower than those with normokinesis (p < 0.01) for both early and delay phases. The % washout of hypokinetic segments were significantly lower than those of normokinetic regions (p < 0.01), while the % washout of akinetic segments were significantly higher than those of severely hypokinetic segments (p < 0.05). Thus, 123I-9MPA myocardial distribution and clearance thought to be associated with left ventricular regional wall motion.

Fatty Acids↗
PubMed1999

[Assessment of left ventricular contraction abnormalities with myocardial infarction using gated technetium-99m sestamibi SPECT: comparison of wall thickening and regional ejection fraction analysis for the detection of coronary artery stenosis].

ECG-gated myocardial Technetium-99m sestamibi SPECT is a useful technique to measure myocardial perfusion and function simultaneously. In this study, wall thickening (WT) and regional ejection fraction (rEF) using ECG-gated SPECT have been studied to determine which parameter would be more sensitive to detect coronary artery stenosis in patients with acute myocardial infarction (AMI). Forty-five patients (36 men, 9 women, mean age 63 +/- 9 years old) with AMI were examined. CAG was performed for all patients. ECG-gated SPECT was performed 60 min after the intravenous injection of 555 MBq 99mTc-sestamibi at rest. Commercially available software (QGS) was used to produce WT and rEF polar maps from acquired SPECT data. The WT and rEF polar maps were evaluated visually and quantitatively. WT indicated higher sensitivity (80.3% vs. 59.1%, p < 0.05) and accuracy (86.7% vs. 74.8%, p < 0.05) than rEF for detecting overall coronary artery stenosis on visual interpretation. On quantitative analysis, WT had higher specificity (91.3% vs. 75.4%, p < 0.05) and accuracy (85.9% vs. 72.6%, p < 0.05) than rEF for detecting overall coronary artery stenosis, and showed a higher specificity (93.8% vs. 59.4%, p < 0.01) and accuracy (88.9% vs. 62.2%, p < 0.01) for detecting LCX stenosis. Moreover, sensitivity of WT for detecting coronary artery stenosis without infarction was higher than that of rEF significantly in quantitative analysis (75.0% vs. 31.3%, p < 0.05). These results suggested that WT was superior to rEF for detecting the coronary artery stenosis in patients with and without myocardial infarction. We concluded that WT is more sensitive indicator to determine localization of regional left ventricular dysfunction in AMI than rEF.

Aged↗
PubMed1999

A role of peptidergic nerves in the internal anal sphincter of Hirschsprung's disease.

BACKGROUND: It is not clear what contribution the internal anal sphincter makes to the impaired motility observed in patients with Hirschsprung's disease (HD). Neuropeptides have recently been shown to be neurotransmitters in the nonadrenergic, noncholinergic inhibitory and excitatory nerves in the human gut. To clarify the physiologic significance of vasoactive intestinal polypeptide and substance P in the internal anal sphincter of HD (aganglionosis), we investigated the enteric nerve responses on lesional and normal internal anal sphincter muscle strips above the dentate line. METHODS: The lesional and normal internal anal sphincter muscle strips above the dentate line were derived from patient with HD (9 cases) and patients who underwent rectal amputation for low rectal cancers (8 cases). A mechanographic technique was used to evaluate in vitro muscle responses to these peptides of adrenergic and cholinergic nerves before and after treatment with various autonomic nerve blockers. RESULTS: Nonadrenergic, noncholinergic inhibitory nerves were found to act on the normal internal anal sphincter but had no effect on the enteric nerves in aganglionosis. Peptidergic (vasoactive intestinal polypeptide and substance P) nerves were found to act on normal colon, but no effect was observed in the aganglionic internal anal sphincter. CONCLUSIONS: These findings suggest that peptidergic nerves play an important role in the impaired motility observed in the internal anal sphincter with HD.

Aged↗
PubMed1998

Rapid data acquisition protocol in ECG-gated myocardial perfusion SPECT with Tc-99m-tetrofosmin.

Into 25 patients with heart disorders, 99mTc-tetrofosmin 555-740 MBq was injected intravenously at rest. After 40 minutes, ECG-gated myocardial perfusion SPECT was performed with a two detector gamma camera VERTEX (ADAC), setting up two detectors to form a 90-degree angle. Sixteen frames per R-R interval were acquired during a 180 degree rotation from the RAO 45 degrees to the LPO 45 degrees. A pair of data sets with standard (SDA) and rapid data acquisition (RDA) protocols was collected. In an SDA protocol, SPECT imaging was performed for 50 sec per step in 5 degree angular steps (total acquisition time; 15 minutes). An RDA protocol was conducted with 12 sec per step, 6 degree angular steps (acquisition time, 3 minutes). LVEF (%) and LVEDV (ml) quantitated automatically with a QGS program showed excellent correlations between two protocols with correlation coefficients of 0.980 (p < 0.01) and 0.983 (p < 0.01), respectively. Subsequently visual assessment of regional wall motion based on a four-point grading system was carried out with a 3-D cine LV display. High complete agreement was gained with 158 (90.3%) out of total 175 segments, so that assessment of the global and regional LV function with the RDA protocol demonstrated high reliability and feasibility.

Electrocardiography↗
PubMed1998

Role of non-adrenergic non-cholinergic inhibitory nerves in the colon of patients with ulcerative colitis.

The cause of impaired colonic motility in patients with ulcerative colitis (UC) is unknown. The non-adrenergic non-cholinergic (NANC) inhibitory nervous system is one of the most important factors in the enteric nervous system of human gut. To assess the physiological significance of NANC inhibitory nerves in the colon of patients with UC, we investigated the enteric nerve responses of colonic tissues from patients with this disease. Colonic tissues were obtained from the lesional sigmoid colons of six patients with UC. Normal sigmoid colonic tissues obtained from ten patients with colonic cancer were used as controls. A mechanographic technique was used to evaluate in-vitro muscle responses to the electrical field stimulation (EFS) of adrenergic and cholinergic nerves before and after treatment with various autonomic nerve blockers. NANC inhibitory nerves were found to act on both normal colon and the lesional colon of patients with UC, but colon with UC was more strongly innervated by NANC inhibitory nerves than was the normal colon. These findings suggest that NANC inhibitory nerves play an important role in the impaired motility observed in the colon of patients with UC.

Adult↗
PubMed1998

[Therapeutic effect of cefluprenam on polymicrobial urinary tract infection associated with Enterococcus faecalis, using the infectious urolithiasis model in rats].

We examined the therapeutic effect of cefluprenam (CFLP) on the polymicrobial urinary tract infection associated with infectious stones as compared to that of ceftazidime (CAZ), using the experimental polymicrobial urinary tract infection caused by Proteus mirabilis (P. mirabilis), Pseudomonas aeruginosa (P. aeruginosa) and Enterococcus faecalis (E. faecalis). In order to form bladder stones in rats, a sterile zinc ring was implanted as a foreign body, followed by inoculating P. mirabilis E05106 transurethrelly. Thereafter, P. aeruginosa E030033 and E. faecalis 966 were inoculated according to the same way. CFLP or CAZ was administered intravenously twice a day for 5 days. The therapeutic effect was evaluated by the eradication of these bacteria from the urine, the kidney and stones, inhibition of growth of stones, and also a value of BUN. The urinary excretion rates of CFLP and CAZ was also determined (20 mg/kg). In result, CFLP significantly more effective in the eradication of P. mirabilitis, P. aeruginosa and E. faecalis from the urine, the kidney and stones than the control than the control (p < 0.05). Furthermore, CFLP significantly more effective in the eradication of P. aeruginosa from the urine and also E. facalis from the urine and stones (p < 0.05). Meanwhile, CAZ significantly more effective in the eradication of P. mirabilis from the urine, the kidney and stones and also P. aeraginosa from the kidney and stones than the control. However, CAZ did not show eradicative effect on E. faecalis. The urinary excretion rates of CFLP and CAZ at rats were 59.3% and 59.4%, respectively, within 8 hrs after administration, showing a similar excretion pattern. CFLP exhibited the prominent therapeutic effect on polymicrobial urinary tract infection associated with infectious stones caused by P. mirabilis, P. aeruginosa and E. faecalls. On the basis of these results, it has been strongly suggested that CFLP is highly beneficial in the management of intractable polymicrobial urinary tract infectious in clinic.

Animals↗
PubMed1997

Relationship between nitric oxide and non-adrenergic non-cholinergic inhibitory nerves in human lower esophageal sphincter.

Nitric oxide (NO) has recently been shown to be a neurotransmitter in the non-adrenergic non-cholinergic (NANC) inhibitory nerves in the gastrointestinal tract. To clarify the the role of NO in the human lower esophageal sphincter (LES), enteric nerve responses in lower esophageal tissue specimens obtained from patients with esophageal cancer (n = 7) and patients with gastric cancer (n = 6) were investigated. A mechanographic technique was used to evaluate in vitro LES muscle responses to electrical field stimulation (EFS) of adrenergic and cholinergic nerves before and after treatment with various autonomic nerve blockers, including NG-nitro-L-arginine (L-NNA) and L-arginine. Findings were: (1) Cholinergic nerves were those mainly involved in the regulation of enteric- nerve responses to EFS in the steady state, and NANC inhibitory nerves acted on the LES; (2) L-NNA concentration-dependently inhibited the relaxation in response to EFS in the LES; and (3) this inhibitory effect in the LES was reversed by L-arginine. These findings suggest that cholinergic and NANC inhibitory nerves play important roles in regulating contraction and relaxation of the human LES, and that NO plays an important role as a neurotransmitter in NANC inhibitory nerves of the human LES.

Electric Stimulation↗