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Y Kondo

Publications and source records attributed to Y Kondo.

At least 415 records · Page 23Linked to original sources
PubMed1995

Amiloride-sensitive Na+/H+ antiporter in basolateral membrane of hamster ascending thin limb of Henle's loop.

The mechanisms of intracellular pH (pHi) regulation were investigated in the in vitro microperfused hamster ascending thin limb (ATL) of Henle's loop with the fluorescent pH indicator, 2',7'-bis(carboxyethyl)-5(6)-carboxyfluorescein. pHi of ATL cells was 7.05 +/- 0.02 (n = 30) when microperfused with a CO2/HCO(3-)-buffered solution. In HEPES-buffered solution, pHi was 7.10 +/- 0.02 (n = 16), which was significantly higher than the value in CO2/HCO(3-)-buffered solution (P < 0.05, n = 16). In HEPES-buffered solution, elimination of Na+ and addition of 1 mM amiloride to basolateral solution decreased the pHi by 0.12 +/- 0.03 (n = 6) and 0.11 +/- 0.02 (n = 5) at 1 min, respectively. The same manipulations in the luminal solution had no effect on pHi. One millimolar of N-ethylmaleimide (NEM) added to either side of ATL caused no significant change in pHi. Elimination of K+ on either side of ATL did not alter pHi. After adding 20 mM NH4Cl to basolateral solution, pHi instantaneously increased from 7.17 +/- 0.01 to 7.51 +/- 0.03 (n = 3), and then returned to steady-state level of 7.21 +/- 0.05 (n = 15) in 3 min. Removal of NH4Cl from basolateral solution then caused a rapid fall in pHi to 6.31 +/- 0.05 (n = 15), followed by spontaneous recovery at a rate of 0.43 +/- 0.06 unit/min (n = 15).(ABSTRACT TRUNCATED AT 250 WORDS)

Amiloride↗
PubMed1995

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)

Animals↗
PubMed1995

Role of calcium in insulin-stimulated NaC1 transport in medullary thick ascending limb.

It has been reported that insulin stimulates directly NaCl transport in the rabbit medullary thick ascending limb (MTAL) [O. Ito, Y. Kondo, N. Takahashi, K. Kudo, Y. Imai, K. Omata, and K. Abe. Am. J. Physiol. 267 (Renal Fluid Electrolyte Physiol. 36): F265-F270, 1994]. In the present investigation, we evaluated the role of Ca2+ in insulin-stimulated NaCl transport in rabbit MTAL by in vitro microperfusion methods. In control experiments, insulin increases transepithelial voltage (Vte) and net lumen-to-bath Cl-flux (JCl). The effects of insulin on Vte and JCl in a Ca2+ -free solution containing ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N' -tetraacetic acid did not differ from those in a Ca2+ -containing control solution. Direct measurements of cytosolic free Ca2+ ([Ca2+]i) with fura 2 fluorescence showed that insulin caused no detectable change in [Ca2+]i in MTAL cells. Chelation of intracellular Ca2+ with the acetoxymethyl ester of 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid inhibited the actions of insulin in Vte and JCl without affecting basal values. We examined further whether calmodulin is also involved in insulin-stimulated NaCl transport in MTAL using two dissimilar inhibitors of calmodulin, trifluoperazine (TFP) and N-(6-aminohexyl)-5-chloro-1-naphthalene-sulfonamide (W-7). TFP and W-7 inhibited the action of insulin in a dose-dependent manner, with maximal inhibition of both agents of > 90%. The half-maximal inhibition by TFP and W-7 was approximately 50 and 100 microM, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

M1 receptors in blood pressure-controlled ischemic spontaneously hypertensive rats.

BACKGROUND AND PURPOSE: Hypertension is a primary aggravating factor in cerebral infarction. An acute rise in blood pressure (BP) at the time of a stroke may be harmful to the brain in a hypertensive subject because both cerebral vascular structure and function are altered by hypertension. Muscarinic M1 receptors are concerned with memory and learning. We aimed to evaluate the effect of controlling BP in hypertensive subjects at the time of stroke with a biochemical index of brain damage. METHODS: We gave a single dose of either the antihypertensive alpha-blocker phentolamine (2 mg/kg IP) or the calcium antagonist nicardipine (2 mg/kg IP) at the start of bilateral carotid artery occlusion to spontaneously hypertensive rats undergoing 3 hours of transient ischemia; we measured the time course of mean BP (MBP) and changes in the M1 receptor and its mRNA in three brain regions 2 weeks after the transient ischemia. RESULTS: Administration of phentolamine or nicardipine not only significantly suppressed the ischemia-induced rise of MBP, it actually decreased MBP during ischemia. In an ischemic control group, M1 receptor binding decreased in the frontal cortex and M1 receptor mRNA increased in the hippocampus 2 weeks after the ischemia. In contrast, both phentolamine- and nicardipine-treated ischemic rats showed no changes in either index compared with sham-operated controls. CONCLUSIONS: Controlling BP during an ischemic insult attenuates ischemia-induced damage of M1 receptors in the brain of spontaneously hypertensive rats. These results suggest that a rapid intensive increase of BP at the time of a stroke may exacerbate brain damage in hypertensive individuals.

Animals↗
PubMed1995

Vasopressin stimulates Cl- transport in ascending thin limb of Henle's loop in hamster.

The effect of arginine vasopressin (AVP) on NaCl transport was investigated in the isolated microperfused hamster ascending thin limb of Henle's loop by measuring transepithelial voltage (Vt) and transmural 22Na+ and 36Cl- fluxes. In the presence of a transmural NaCl concentration gradient (100 mM higher in the lumen), Vt was 8.4 +/- 0.4 mV. Addition of 1 nM AVP to the basolateral solution increased Vt to 9.6 +/- 0.4 mV, which corresponds to an increase in the Cl- to Na+ permselectivity ratio (PCl/PNa) from 2.8 +/- 0.2 to 3.4 +/- 0.2. AVP at physiological concentrations increased Vt in a dose-dependent manner with an ED50 of 5 pM. AVP increased the Cl- efflux coefficient from 99.6 +/- 6.3 to 131.4 +/- 10.6 x 10(-7) cm2/s without affecting the Na+ efflux coefficient. 5-Nitro-2-(3-phenyl-propylamino)-benzoate (0.2 mM), a Cl- channel inhibitor, in the perfusate decreased the basal Cl- efflux coefficient and inhibited the AVP-induced increase in this parameter. The AVP-induced increase in Vt was not affected by [d(CH2)5(1),O-Me-Tyr2,Arg8] vasopressin, a V1 receptor antagonist, but was abolished by [d(CH2)5,D-Ile2,Ile4,Arg8] vasopressin, a V2 receptor antagonist. The selective V2 agonist dDAVP in 1 nM also increased Vt from 8.6 +/- 0.7 to 9.5 +/- 0.6 mV. Dibutyryl cAMP and forskolin both increased Vt, whereas H89, an inhibitor of cAMP-dependent protein kinase, abolished the AVP-induced increase in Vt. These results demonstrate that AVP stimulates Cl- transport in the ascending thin limb of Henle's loop by activating Cl- channels via a signal transduction cascade comprising V2 receptors, adenylate cyclase, and cAMP-dependent protein kinase. The ascending thin limb of Henle's loop thus participates in the formation of concentrated urine as one of the target renal tubular segments of AVP.

Adenylyl Cyclases↗
PubMed1995

Thyrotropin-induced hydrogen peroxide production in FRTL-5 thyroid cells is mediated not by adenosine 3',5'-monophosphate, but by Ca2+ signaling followed by phospholipase-A2 activation and potentiated by an adenosine derivative.

The production of hydrogen peroxide (H2O2) as an essential process for iodide organification is a key reaction in TSH-induced thyroid hormone synthesis. Here we characterize the signal transduction pathway involved in TSH-induced H2O2 production in FRTL-5 thyroid cells. At higher than 1 nM TSH, N6-(L-2-phenylisopropyl)adenosine (PIA), an adenosine receptor agonist having, by itself, no influence on H2O2 generation, potentiated this TSH action, whereas the TSH increase and PIA addition reduced cAMP accumulation. RO 20-1724, a phosphodiesterase inhibitor, amplified the TSH-induced cAMP accumulation, but did not change H2O2 generation in the whole range of TSH used. Ca(2+)-mobilizing agonists, GTP and ATP, also induced H2O2 production without stimulating cAMP accumulation. Chelation of intracellular Ca2+ markedly inhibited the TSH action, but intracellular Ca2+ increases by either thapsigargin or ionomycin mimicking it. All of the findings show the participation of Ca2+, but not cAMP, in the action of TSH. Desensitization of protein kinase-C (PKC) did not influence the receptor-mediated H2O2 production, suggesting the reduced importance of PKC activation compared to Ca2+ signaling to the reaction. A rise in intracellular Ca2+ independent of receptor activation also induced H2O2 production as well as arachidonate release, and both were potentiated by PIA. In addition, inhibitors of phospholipase-A2 and the arachidonate metabolic pathway depressed H2O2 generation, suggesting the participation of an arachidonate cascade in the Ca(2+)-dependent H2O2 production. Lipoxygenase inhibitors depressed the Ca2+ action without influencing arachidonate release, suggesting the involvement of a lipoxygenase product(s) of arachidonate in the Ca(2+)-signaling mechanism. In conclusion, in FRTL-5 cells, TSH-induced H2O2 production is mediated not by cAMP, but by the phospholipase-C/Ca2+ cascade, possibly followed by the Ca(2+)-dependent phospholipase-A2/arachidonate cascade. PIA amplifies TSH-induced H2O2 production at the steps of phospholipase-C and phospholipase-A2 activation in a pertussis toxin-sensitive manner.

Adenosine↗
PubMed1995

Cooperation of thyrotropin, but not basic fibroblast growth factor, with an adenosine receptor agonist in Ca2+ mobilization from thapsigargin-sensitive pools in single FRTL-5 thyroid cells.

TSH-induced intracellular Ca2+ concentration ([Ca2+]i) changes in single FRTL-5 thyroid cells were analyzed by digital video imaging of fura-2-loaded cells. More than 80% of the cells responded to as little as 30 nM TSH, resulting in a [Ca2+]i rise in the presence and absence of extracellular Ca2+. One micromolar concentration of N6-(L-2-phenylisopropyl)adenosine (PIA) caused no appreciable [Ca2+]i increase in more than 300 cells examined, but induced the [Ca2+]i elevation in more than 90% of the cells that had previously been treated with TSH. Pertussis toxin treatment abolished the PIA, but not the TSH, action, whereas thapsigargin-induced Ca2+ depletion of the inositol 1,4,5-trisphosphate-sensitive pool inhibited the actions of both TSH and PIA. The time courses of Ca2+ response considerably differentiated among single cells, but showed similarity among different areas in each cell. These results suggest that PIA induces Ca2+ release from the same thapsigargin-sensitive pool as that targeted by TSH. The lack of PIA stimulation of basic fibroblast growth factor-induced phospholipase-C gamma activation as well as the rise in [Ca2+]i suggests that the cooperative PIA action occurs specifically on phospholipase-C beta.

Animals↗
PubMed1995

[A study on the relationship between sensitivity to CDDP and inducibility of metallothionein and glutathione of genitourinary tumors].

BACKGROUND: In this paper we demonstrate the relationship between the antitumor activity of cis-diamminedichloroplatinum (II) (CDDP) and inducibility of metallothionein (MT) and glutathione (GSH) of genitourinary tumors. METHODS: The chemosensitivity test was performed in athymic mice bearing tumors derived from the human tumor cell lines: ACHN (renal cell carcinoma), NMB-1 (urinary bladder transitional cell carcinoma), and NMT-1 (testicular embryonal cell carcinoma). A single dose of CDDP (25 mumol/kg body weight), was administered i.p. to athymic tumor bearing mice. Concentrations of platinum, MT, and GSH were measured in organ and tumor homogenates 24 h after CDDP administration. RESULTS: We observed that tumors derived from NMB-1 and NMT-1 were very sensitive to CDDP, but ACHN derived tumors were resistant to CDDP. Measurement of platinum concentrations in tumor tissues revealed no correlation to the observed chemosensitivities of the tumors. Furthermore, 24 h after CDDP administration, the levels of MT and GSH in NMB-1 and NMT-1 derived tumors were lower them or equal to those of control mice. In contrast, mice bearing tumors derived from ACHN exhibited a 1.7-fold and a 2.1-fold increase in MT and GSH, respectively, as compared to control mice. CONCLUSION: These findings suggest that the inducibility of MT and GSH in tumor tissues following CDDP administration may be a contributing factor in the development of CDDP resistance in renal cell carcinoma.

Animals↗
PubMed1995

Cholecystokinin alterations and effects of levodopa administration in the MPTP-treated mouse brain.

To clarify the effects of levodopa administration on MPTP-induced alterations in neuropeptides, we examined the effects of repeated levodopa injections (200 mg/kg i.p.) for 2 weeks starting 4 weeks after 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) treatment (30 mg/kg i.p. twice/day for 5 days) on cholecystokinin-octapeptide (CCK-8), substance P (SP) and thyrotropin-releasing hormone (TRH) concentrations at 6 weeks after the MPTP treatment. In the striatum, CCK-8 significantly but slightly decreased in the MPTP-treated mice, coinciding with the MPTP-induced marked reduction of dopamine (DA). This considerable reduction of striatal CCK-8 may result from the selectivity of MPTP since the mesolimbic DA neurons coexisting with CCK-8 are intact with the MPTP treatment. Furthermore, this MPTP-induced decrease in CCK-8 persisted with repeated levodopa administration; therefore, the ineffectiveness of the levodopa treatment may have been be due to the degeneration of the nigrostriatal DA neurons. SP and TRH contents showed little or no change with levodopa treatment in the MPTP-treated mouse brain. The CCK-8 level decreased in the thalamus+midbrain, hippocampus and hindbrain of the MPTP+levodopa-treated group, although there were no changes in the MPTP-treated controls. These results suggest that DAergic neurons, except those in the nigrostriatum, strongly interact with the CCK neurons in these brain regions.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1995

[Electrolyte metabolism in renal tubules].

Obese, diabetic and hypertensive populations have an increased prevalence of hyperinsulinemia and insulin resistance with respect to glucose metabolism. Insulin is thought to contribute to hypertension by sodium retention in the kidney. Here we describe the direct effect of insulin on renal tubular transport. The ascending thin limb of Henle's loop (ATL) plays an important role in concentrating urine. However, it is still controversial whether Na+ reabsorption in this nephron segment is an active process or a passive one. Moreover hormonal regulation of Cl- transport in the ATL is completely unknown. Therefore we also describe the mechanism of Na+ transport and hormonal regulation of Cl- transport in the ATL.

Animals↗
PubMed1995

Clinical effectiveness of lansoprazole in patients with gastric ulcers: evaluation of quality of ulcer healing based on endoscopic ultrasonographic findings.

The effects of lansoprazole (30 mg/day) in 18 patients with gastric ulcers and the quality of ulcer healing were studied using endoscopy (including dye endoscopy) and endoscopic ultrasonography (EUS). The results showed an 8-week endoscopic healing rate of 94.4% and an S2-stage shift rate of 11.1%. In dye endoscopic findings of 11 S1-stage patients, S1b healing with regenerated mucosa close to S2 was seen in 63.6%. In a study of EUS findings, E0 with few relapses and high quality of healing accounted for 44.4%. When E0 rates were compared with the scarring images seen in endoscopic findings, the rates were 100% for S2, 66.7% for S1b, and 33.3% for S1a. These results indicate that a high degree of ulcer healing was achieved with lansoprazole, as good contraction of the ulcer tissue and early maturation of regenerated epithelium were observed.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed1995

Immediate hypersensitive reactions to buckwheat ingestion and cross allergenicity between buckwheat and rice antigens in subjects with high levels of IgE antibodies to buckwheat.

BACKGROUND: Immediate hypersensitive reactions induced by buckwheat ingestion are considered to be IgE-mediated. Some subjects, however, develop no immediate adverse reactions after buckwheat ingestion despite high levels of buckwheat-specific antigens IgE. The mechanism is unknown. OBJECTIVE: To investigate the mechanisms. METHODS: RAST for buckwheat and rice and RAST inhibition between these antigens were performed using sera from 23 buckwheat-sensitive subjects and 30 buckwheat-tolerant subjects who had IgE antibodies for both buckwheat and rice. RESULTS: RAST values for buckwheat and rice were significantly correlated with each other (P < .01) in the buckwheat-tolerant group, but not in the buckwheat-sensitive group. This suggests the IgE antibodies from the subjects without any overt symptoms after buckwheat ingestion recognize the cross-reactive epitope between buckwheat and rice, whereas the IgE antibodies from those with immediate reactions to buckwheat ingestion do not. RAST inhibition assays were performed to evaluate this. RAST inhibition of heterogeneous combination of inhibitor and disc antigen such as rice and buckwheat was significantly smaller than that of homologous combination of rice and rice or buckwheat and buckwheat in the group with immediate symptoms after buckwheat ingestion. There was no significant difference in RAST inhibition between homologous and heterogeneous combinations in the group without the symptoms. CONCLUSIONS: There was cross-reactivity with IgE antibodies between buckwheat and rice and IgE antibodies from the buckwheat-tolerant subjects with high levels of IgE antibodies from the buckwheat might recognize the epitopes on buckwheat antigens which cross-react with rice antigens, whereas IgE antibodies from the buckwheat-sensitive subjects might bind to buckwheat-specific epitopes.

Adolescent↗
PubMed1995

[Adeno-tonsillectomy after cardiac transplantation in a child].

A case report of a boy who had a heart transplant at age one, and an adeno-tonsillectomy at age 2 years and 2 months, is presented. The patient showed severe episodic hypoxemia and poor weight gain (below 3 SD) due to upper airway obstruction caused by enlarged adenoids and tonsils. He was very active and no signs of congestive heart failure were noted. General anesthesia was induced with thiopental and maintained with a balanced anesthesia of nitrous oxide, oxygen, fentanyl, and vecuronium bromide. The heart rate did not increase with endotracheal intubation nor adenoidectomy but heart rate and blood pressure did increase slowly by the time the tonsillectomy was performed. Arrhythmia did not appear throughout the procedure and anesthesia was uneventful. A nasal endotracheal tube was kept in place for 4 days until surgical edema subsided. Respiratory inductive plethysmography performed before surgery and 2 days after extubation showed improvement of upper airway obstruction. The patient's blood concentration of cyclosporine fell briefly below the optimal level perioperatively due to unavailability of intravenous preparation in Japan. Various aspects of non-cardiac anesthesia for children who have experienced cardiac transplants are discussed.

Anesthesia, General↗
PubMed1995

[Biodistribution of radiolabeled F(ab')2 fragment of monoclonal antibody Nd2 and gamma-interferon enhancement on tumor localization in nude mice with human pancreatic tumor xenografts].

Nd2 is a murine monoclonal antibody of subclass IgG1 directed against purified mucin of human pancreatic cancer cell line SW1990. A previous biodistribution and radioimmunoimaging study of Nd2 demonstrated that the tumor accumulation rate of Nd2 was excellent and that apparently positive images of xenografts could be obtained using indium-111-labeled Nd2. In this study, I first investigated the biodistribution of F(ab')2 fragment on Nd2 on SW1990 bearing nude mice. I then tested the effects of intraperitoneally administered IFN-gamma on the rate of accumulation of Nd2 in the xenografts. F(ab') fragment of Nd2 showed more rapid maximal accumulation in the tumor and more urinary excretion in earlier period than whole Nd2. F(ab')2 fragment in the blood was lower in response more urinary excretion and tissue to blood ratio was therefore much higher than that of whole Nd2 at 12 hours and 1 day after administration. The biodistribution study to determine the effects of IFN-gamma on SW1990 bearing nude mice demonstrated that the accumulation rate of Nd2 in the tumor receiving intraperitoneal administration of IFN-gamma was significantly higher than that of control group. The results of these studies suggest that F(ab')2 fragment of Nd2 is useful in some respects in clinical use and that supplementary use of IFN-gamma may improve the rate of accumulation in the tumor.

Animals↗
PubMed1995

[Hypotonous maculopathy following trabeculectomy with mitomycin C].

We retrospectively studied incidence, prognosis and predictive factors of hypotonous maculopathy following trabeculectomy with adjunctive mitomycin C. The subjects were 208 cases (208 eyes) with various types of glaucoma with clear media, who were followed up for at least three months postoperatively. The follow up periods ranged from 3 to 44 months with a mean of 21.1 months. The incidence of the maculopahy was 9.1% (19/208). The postoperative intraocular pressures (IOPs) varied between 1 and 6 mmHg in the presence of maculopathy. The maculopathy disappeared in 14 eyes (74%) spontaneously or following ocular hypertensive therapy including application of trichloracetic acid and subconjunctival injection of autologous blood. The final visual acuity deteriorated two lines or more in 8 eyes (42%). A discriminant analysis showed that age, history of intraocular surgery, preoperative maximum IOP, and mean deviation are the predictive factors for maculopathy. As compared with the hypotonous eyes without maculopathy, those with maculopathy tended to be younger and to have less severe visual field changes.

Adolescent↗
PubMed1995

Two cases of early gallbladder cancer incidentally discovered by laparoscopic cholecystectomy.

In case 1, a 68-year-old woman with asymptomatic gallstones underwent laparoscopic cholecystectomy after radical mastectomy for breast cancer. Histological examination revealed gallbladder carcinoma with involvement confined to the mucosa and positive margin at the cystic duct. We resected the remnant cystic duct with open laparotomy. In case 2, a 63-year-old woman with a diagnosis of early rectal cancer underwent laparoscopic cholecystectomy for silent gallstones following transanal resection of the rectal tumor. Pathologic analysis illustrated a gallbladder carcinoma with wide mucosal spread and minimal invasion into the subserosal layer. No additional treatment was warranted. As laparoscopic cholecystectomy has become widely used, an increase in the number of resected cases of early gallbladder cancer can be expected, especially among asymptomatic gallstone patients. Additional treatment should be determined through meticulous microscopic investigation of the specimen, with special attention to the depth of invasion and the range of mucosal spread.

Adenocarcinoma↗
PubMed1995

New aerodynamic aspects of nasal patency.

In considering possible aerodynamic indicators of subjective nasal stuffiness, we measured nasal resistance, acceleration change of nasal airflow, and alteration of differential pressure and compared those with the degree of severity of sensation of nasal obstruction in 75 patients. The acceleration change of airflow and alteration of differential pressure are presented as an equation: y = ax2 + bx + c, in which "a" represents the approximate shape of the curve. Nasal resistance, on either inspiration or expiration, and coefficient "a" of acceleration change the rapid phase from inspiration to expiration correlated well with subjective nasal patency, while coefficient "a" of acceleration change the rapid phase from expiration to inspiration and alteration of differential pressure either the rapid phase from inspiration to expiration or from expiration to inspiration did not correlate well with perception of nasal blockage. It seems that measurement of respiratory acceleration of airflow of quiet nasal breathing is a useful indicator of subjective nasal patency.

Acceleration↗