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T Morita

Publications and source records attributed to T Morita.

At least 55 records · Page 3Linked to original sources
PubMed2002

Comparison of insulinotrophic actions of nateglinide with glibenclamide dissociated from absorption in conscious dogs.

Nateglinide is more rapidly absorbed than glibenclamide. Therefore, the different absorption kinetics of both drugs were eliminated by intraportal administration in conscious fasted dogs. The plasma insulin profiles were compared under similar kinetic changes in plasma drug concentrations. After a priming dose of nateglinide (1 mg/kg. 5 min) or glibenclamide (40 microg/kg. 5 min), plasma drug concentrations reached a peak at 4 minutes (nateglinide, 80 +/- 5 micromol/L, n = 6 and glibenclamide, 263 +/- 60 nmol/L, n = 6) followed by a sustained level at approximately 30% of the peak concentration at 30 minutes. Nateglinide led to a rapid and constant reduction in arterial glucose of approximately 30% basal, while glibenclamide promoted a gradual decrease to approximately 50% basal at 120 minutes. An increase in plasma insulin level by nateglinide of 4 times basal (218 +/- 58 pmol/L v 47 +/- 3 pmol/L, P <.05, n = 6) occurred at 6 to 10 minutes followed by sustained release of 1.4 times basal (67 +/- 15 pmol/L, n = 6). The insulin surge was more than doubled (484 +/- 209 pmol/L, n = 6) under a euglycemic clamp. Insulin release by glibenclamide increased gradually reaching 10-fold basal (449 +/- 166 pmol/L, n = 6) at 60 minutes. This was not enhanced during a euglycemic clamp. Lowering the primed doses of nateglinide resulted in a diminished peak plasma insulin concentration. In contrast, glibenclamide caused only a slower increase, but eventually reaching a similar peak. By increasing the continuous infusion of nateglinide, the sustained insulin release was not altered. Glibenclamide, but not nateglinide, evoked prompt and sustained insulin release in the continuing presence of the other. These results are consistent with the concept that nateglinide produces a quick, but very short-lived, interaction with sulfonylurea (SU)-receptors on plasma membrane by free access of the drug from the cell exterior. In contrast, glibenclamide promotes a slow and longer interaction with the receptor by distribution of the drug into the cell inferior. We conclude, therefore, that not only the different kinetics of gastrointestinal (GI) absorption, but also the inherent difference in the interaction with beta cells is attributed to the different insulin release characteristics between nateglinide and glibenclamide in vivo.

ATP-Binding Cassette Transporters↗
PubMed2002

Visualization of inositol 1,4,5-trisphosphate receptor type III with green fluorescent protein in living cells.

Inositol 1,4,5-trisphosphate receptor (IP3R) is an intracellular Ca2+ channel that releases Ca2+ into the cytosol and its subcellular distribution is believed to have significant effects on Ca2+ signalling. We constructed a plasmid vector containing full-length rat type 3 IP3R linked to GFP (GFP-IP3R) for expression in mammalian cells. Western blot analyses revealed that the expressed fusion protein contained both GFP and full-length type 3 IP3R. Fluorescence confocal microscopy showed that the fluorescence of GFP-IP3R3 was distributed to reticular network structures, even after cell permeabilization with saponin. We further visualized intracellular membranes with DiOC6, a vital fluorescent marker for intracellular membranes, and provide evidence that the distribution of GFP-IP3R3 overlaps with the distribution of the endoplasmic reticulum. Our results indicate that GFP-IP3R3 can be used to visualize IP3R in living cells, and pave the way for subsequent mutational and functional studies.

Amino Acid Sequence↗
PubMed2002

Biopsy pathology predicts patients with ulcerative colitis subsequently requiring surgery.

BACKGROUND: The clinical course of patients with ulcerative colitis (UC) is unpredictable, and 17%-38% ultimately require surgery. We hypothesized that mucosal histology may differ between patients requiring surgery and those receiving medication alone. The aim of this study was to elucidate comprehensive criteria consisting of specific histologic features enabling the prediction of failure to medical treatment. METHODS: We studied colorectal biopsy specimens from 67 patients ultimately requiring surgery (UC-S) and 90 receiving medication alone for more than 3 years (UC-M), and conducted multiple logistic regression analysis on 70 histologic features together with endoscopic disease extent and patient age. The analysis constructed an equation finding probability of UC-S (P(UC-S)). Based on a receiver-operating characteristic curve, we selected four cut-off values of P(UC-S), and determined criteria of five categories: highest-risk, higher-risk, unpredictable, lower-risk and lowest-risk of surgery. Sensitivity and specificity of criteria were evaluated in a 2 x 5 table. RESULTS: Statistically significant features predicting UC-S were deep ulceration (X1), frequent crypt abscesses (X2), focal and segmental mononuclear cell infiltration (X3 and X4), paucity of eosinophils (X5: eosinophil infiltration) and wide extent of the disease (X6). The regression equation was as follows: logitP(UC-S) = -16.26 + 3.20X1 + 4.83X2 + 11.65X3 + 5. 10X4 - 5.59X5 + 5.53X6. Higher-risk and lower-risk showed sensitivity exceeding 91.0% and specificity exceeding 98.5% in predicting the outcome. CONCLUSIONS: Our criteria incorporating specific histologic features and endoscopic disease extent reliably predict eventual clinical outcome, and are expected to prove useful in determining the necessity of surgery.

Adult↗
PubMed2002

A scale to measure satisfaction of bereaved family receiving inpatient palliative care.

Although satisfaction is an important outcome of medical care, there are no validated tools to quantify family satisfaction with hospital-based palliative care. In this nationwide postal survey, an instrument to measure informal carer satisfaction with an inpatient palliative care service was validated. A 60-item questionnaire was mailed to 1344 bereaved people who had lost their family members at 50 palliative care units in Japan, and 850 responses were analysed (response rate = 64%). The reliability, construct validity, and convergent validity of the scale were examined after the responses were randomly divided into two groups: a training set used in the development phase (n = 500) and a testing set used in the validation phase (n = 350). The number of scale items was reduced from 50 to 34 through psychometric techniques in the development phase. In the testing sample, the overall Cronbach's coefficient alpha for the final 34-item scale was 0.98. A factor analysis revealed that the scale consisted of seven subcategories: Nursing Care, Facility, Information, Availability, Family Care, Cost, and Symptom Palliation. The total score of the scale was significantly correlated with the degree of global satisfaction of the bereaved (Spearman's rho = 0.78). In conclusion, this 34-item scale, the Satisfaction Scale for Family Members Receiving Inpatient Palliative Care (Sat-Fam-IPC), has acceptable psychometric properties and would be a useful tool to measure carer satisfaction with an inpatient palliative care service.

Bereavement↗
PubMed2002

Family satisfaction with inpatient palliative care in Japan.

Whereas satisfaction is one of the most important outcomes in palliative care settings, there have been no systematic studies investigating the effects of family- and organization-related variables on family satisfaction with care. To clarify factors contributing to family satisfaction with inpatient palliative care services, a cross-sectional mailed survey was performed. A 60-item questionnaire was mailed to 1026 bereaved subjects who had lost family members at one of 37 palliative care units in Japan to evaluate their sociodemographic characteristics and satisfaction levels with care. An institution survey was performed to collect organization-related variables. Caregiver satisfaction was rated on the Satisfaction scale for Family members receiving Inpatient Palliative Care (Sat-Fam-IPC). A total of 640 responses were analysed (response rate = 62%). The responses to overall satisfaction were 'satisfied' in 41 % and 'very satisfied' in 47%. The mean total score of the Sat-Fam-IPC was 82.4 +/- 13.2 on the 0-100 scale. The mean subscale scores were: 85.8 +/- 14.5 (Nursing Care), 81.5 +/- 18.4 (Symptom Palliation), 85.0 +/- 13.8 (Facility), 83.3 +/- 16.6 (Information), 83.1 +/- 17.3 (Availability), 78.3 +/- 18.9 (Family Care), and 79.8 +/- 17.3 (Cost). Significant determinants of family satisfaction identified were: nursing system, the number of nurses at night and presence of attending medical social workers (Nursing Care), patient age and the number of physicians (Symptom Palliation), floor space per bed (Facility), duration of admission and presence of attending medical social workers (Availability), patient age, family age, gender and occupational status (Family Care), patient age and the extra charge for a private room (Cost). In conclusion, informal caregivers are generally satisfied with inpatient palliative care services provided by members of the Japanese Association of Hospice and Palliative Care Units. The levels of satisfaction are influenced by various family- and organization-related variables.

Aged↗
PubMed2002

Myofiber expression of class I major histocompatibility complex accompanied by CD8+ T-cell-associated myofiber injury in a case of canine polymyositis.

A 7-year-old female Labrador Retriever dog showed extreme muscular weakness, muscle wasting, dysbasia, and mild dysphagia. An elevated value of creatine kinase (335 IU/liter) in the serum was detected. Electromyographic findings included increased insertional activity, fibrillation potentials, and bizarre high-frequency repetitive potentials. Histopathologic examination of skeletal muscles revealed myofiber necrosis and phagocytosis, regeneration of myofibers, and perivascular, perimysial, and endomysial infiltrations of lymphocytes, macrophages and plasma cells. Immunohistochemical evaluation demonstrated that infiltrative cells in the early stage of myositis were CD8+ T-cells and that an increased expression of major histocompatibility complex (MHC) class I was apparent on the surface of nonnecrotic muscle fibers. In contrast, many CD3+ cells (T cells) and HLA-DR-positive macrophages and B lymphocytes were found in the severely affected areas. These results suggest that both expression of MHC class I and CD8+ T-cell infiltration may play an important role in initiation of myositis. These histopathologic findings resemble those reported in naturally occurring polymyositis in humans.

Animals↗
PubMed2002

Cliniconeuropathologic findings of familial frontal lobe epilepsy in Shetland sheepdogs.

We examined an epileptic focus by electroencephalography (EEG) by using an international 10-20 electrode system in 11 Shetland sheep dogs affected with familial idiopathic epilepsy. We also performed an evaluation of the amino acids in the cerebrospinal fluid (CSF) and a pathologic examination of the brains of 8 dogs that died from status epilepticus. Continuous electroencephalography demonstrated that an epileptic focus was initially detected in the frontal lobe, particularly the internal area, and that paroxysmal foci developed diffusely in other lobes of affected dogs with recurrent convulsions. The EEG analyses indicated spike and sharp wave complexes, which were considered to be paroxysmal discharges. An increased value for glutamate or aspartate was found in the CSF of some epileptic dogs. Histologically, acute neuronal necrosis and astrocytosis were distributed predominantly in the cingulate cortex and internal area of frontal cortex, less frequently in other areas of the cerebrum. The results of this study suggest that, initially, the dogs have an epileptic focus in the frontal lobe, and that the focus extends gradually to other areas of the cerebrum. Based on the distribution of neuronal necrosis and astrocytosis, acute neuronal damage may be related to the superexcitation of neurons following epilepsy.

Amino Acids↗
PubMed2002

[Esophagopericardial fistula occurring at the 22nd years after operation for achalasia presenting as myopericarditis].

We describe a case of pneumopericardium that resulted from esophagopericardial fistula occurring at the 22nd years after operation for achalasia in a 52-year-old male. Atypical features on initial examination suggested myopericarditis or congestive heart failure. A chest roentgenogram and computed tomography revealed development of pneumopericardium. Subsequent emergent pericardiocentesis relieved cardiac tamponade and enabled us to diagnose pyopneumopericardium and esophagopericardial fistula in postoperative period. The esophagopericardial fistula was surgically closed. However, the patient died 2 weeks postoperation of hemorrhage from duodenal ulcer. Autopsy confirmed the pre-mortem diagnosis of esophagopericardial fistula without evidence of malignancy. Early diagnosis and subsequent treatment appears to be most important. This case report reinforces the difficulty of this diagnosis and perhaps the need for clinical awareness and inclusion of this entity in a differential diagnosis.

Cardiac Tamponade↗
PubMed2002

Acute endocapillary proliferative glomerulonephritis associated with human parvovirus B19 infection.

A 36-year-old female developed acute nephritic syndrome associated with human parvovirus B19 (HPVB19) infection. Laboratory data showed proteinuria, hypocomplementemia, mild pancytopenia, the presence of immunoglobulin (Ig) M and IgG antibodies to HPVB 19 and positive reaction of serum HPVB19 DNA using a polymerase chain reaction (PCR). A renal biopsy showed endocapillary hypercellularity mainly of mononuclear cells with segmental apparent mesangiolytic change; fine granular IgM, IgG and C3 deposits were noted by immunofluorescence microscopy; relatively small electron-dense deposits were observed in the widened subendothelial spaces and the mesangium, and loosening of the mesangial matrix varied from place to place electron microscopically. PCR of HPVB19 DNA in the renal biopsy tissue was positive as well as in the peripheral blood. The histological findings suggested that immune-complex-mediated endocapillary proliferative glomerulonephritis is caused by acute HPVB 19 infection. We discuss the differences from poststreptococcal glomerulonephritis and the possible pathogenesis of acute endocapillary proliferative glomerulonephritis associated with HPVB19 infection.

Acute Disease↗
PubMed2002

[Comparison of the prothrombin levels between the patients with atrial fibrillation and patients with cardiac pacemaker implantation due to sick sinus syndrome during anticoagulation therapy with warfarin].

We measured the fully carboxylated prothrombin levels using the Carinactivase-1 (CA-1) test and thus compared prothrombin levels between patients having atrial fibrillation (Af) without pacemaking and those having sick sinus syndrome due to Af with cardiac pacemaker implantation during anticoagulation therapy with warfarin. Total plasma samples were assayed for the CA-1 test, the prothrombin time international normalized ratio (PT-INR) and the thrombotest (TT). This prospective randomized study was carried out on 641 samples obtained at the Fukuoka University Hospital Department of Cardiovascular Surgery between May 1997 and March 1999. The patients were divided into 2 groups consisting of: group A; 144 patients having sick sinus syndrome due to Af implanted with a cardiac pacemaker who were treated with warfarin, group B; 497 patients atrial fibrillation without pacemaking who were treated with warfarin. The prothrombin levels in each group were 65.5 +/- 25.2 and 76.1 +/- 47.7 micrograms/ml, respectively. The normal prothrombin levels of group A decreased more significantly than in group B. Therefore, the PT-INR and TT were not significantly different between groups A and B. The dose of warfarin in each group was 2.4 +/- 1.0 and 2.6 +/- 1.4 g/day, respectively. The dose of warfarin in group A therefore decreased significantly different more than in group B. In conclusion, the normal prothrombin levels of patients atrial fibrillation increased more significantly than patients having sick sinus syndrome due to Af implanted with a cardiac pacemaker.

Aged↗
PubMed2001

Risk factors for massive hemoptysis after endobronchial brachytherapy in patients with tracheobronchial malignancies.

BACKGROUND: Massive and mostly fatal hemoptysis is a frequently reported morbidity after endobronchial brachytherapy (EBB) for tracheobronchial malignancies. However, to the authors' knowledge, it remains controversial whether this morbidity is related directly to EBB. To investigate whether massive hemoptysis is related to EBB, the authors retrospectively analyzed risk factors for massive hemoptysis after EBB. METHODS: Thirty-six patients (30 men and 6 women) with a mean age of 70 years underwent high-dose rate EBB for tracheobronchial malignancy using a cobolt-60 (Co-60) afterloading machine. EBB was performed as primary therapy in 6 patients and as salvage treatment for recurrent disease in 30 patients. EBB was delivered to the tracheal lesions in 15 patients and to the main bronchial lesions in 21 patients. EBB was combined with external beam radiation therapy (EBRT) in 24 patients, with laser photocoagulation in 3 patients, and with EBRT plus laser photocoagulation in 5 patients. The dose of EBRT delivered with the EBB ranged from 16-69 grays (Gy), with a mean dose of 37 Gy. RESULTS: At a mean follow-up of 18 months, 33 of the 36 patients had died. Eight of the 33 patients had no evidence of local disease at the time of death. Seven patients died of massive hemoptysis. The cumulative rate of massive hemoptysis was 29.4% at 2 years. According to univariate analysis, no statistically significant correlation with massive hemoptysis was observed for EBRT dose delivered in combination with EBB, EBB fractional and total doses, EBB length, and the sum of all the EBRT doses including that used for the initial treatment. Local failure or persistent malignancy (P = 0.033) and delivery of laser photocoagulation (P = 0.032) were found to be statistically significantly associated with massive hemoptysis. Direct contact between the EBB applicator and the tracheobronchial walls at the vicinity of the great vessels was observed in 16 patients and was found to be statistically significantly associated with massive hemoptysis (P = 0.003). In six patients, the applicator was in direct contact with two or more tracheobronchial walls at the vicinity of the great vessels; all these patients died of massive hemoptysis. CONCLUSIONS: Direct contact between the EBB applicator and the tracheobronchial walls at the vicinity of the great vessels was one of the significant risk factors for massive hemoptysis. To prevent massive hemoptysis, a specific spacer should be employed to maintain a safe distance between the applicator and the bronchial wall.

Aged↗
PubMed2001

Crystal structure of bitiscetin, a von Willebrand factor-dependent platelet aggregation inducer.

Bitiscetin, a C-type lectin-like protein isolated from the venom of the snake Bitis arientans, promotes the interactions between plasma von Willebrand factor (VWF) and platelet membrane glycoprotein Ib (GPIb) to induce platelet aggregation. We report here the crystal structure of bitiscetin at 2.0 A resolution. The overall fold is similar to those of coagulation factor IX/X-binding protein (IX/X-bp) and flavocetin-A (a GPIb-binding protein), although these three proteins are functionally distinct from one another. The characteristic property determining target recognition is explained mainly by the differences in the surface potential on the central concave surface. A negatively charged patch on the surface of bitiscetin is a candidate for the site of binding to the positively charged surface of the VWF A1 domain, as shown in the case of another platelet aggregation inducer, botrocetin. However, a positively charged patch near the central concave surface is unique for bitiscetin and suggests that it is the binding site for the negatively charged surface of the VWF A3 domain. Thus, the interactions accounting for VWF activation by bitiscetin possibly involve both the A1 and A3 domains of VWF, indicating a specific mechanism of VWF activation by bitiscetin.

Amino Acid Sequence↗
PubMed2001

Improvement of a mediator-type biochemical oxygen demand sensor for on-site measurement.

We characterized a mediator-type biochemical oxygen demand (BOD) sensor with a three-electrode system using potassium ferricyanide (FC) and Pseudomonas fluorescens in our previous study. In the present study, we have utilized the advantages of a mediator-type biosensor, which does not require air-supply equipment for on-site measurements, and made a fully disposable sensor tip for a portable device. The tip consists of a two-electrode system with P. fluorescens immobilized on a cellulose acetate membrane and is packaged in polyester film to prevent it from drying out. By aeration with a 0.1 M NaCl solution of P. fluorescens (after growth), the sensor responses as well as their reproducibility and stability have been successfully improved. The responses increased more than seven times, and the calibration curve from 15 to 260 mg l(-1) also remained linear although the response decreased approximately half the original after at least 35 days in storage. The reproducibility of the sensor responses improved to 12.7% (average of relative standard deviations (RSDs)) in the calibration curve obtained by using the Organization for Economic Cooperation and Development synthetic sewage. Examination of real samples from three different sources showed that the BOD as determined by the sensor correlates well with the conventional 5-day BOD method (r(2)=0.982, 0.823, and 0.809). Consequently, the aeration process makes it possible to realize rapid, and in situ measurements without the long conditioning process that is generally required to activate the microorganisms immobilized on bio-films before use. Finally, we have designed a portable device that utilizes our disposable sensor tip.

Biosensing Techniques↗
PubMed2001

Vascular smooth muscle cell-directed overexpression of heme oxygenase-1 elevates blood pressure through attenuation of nitric oxide-induced vasodilation in mice.

To elucidate pathophysiological roles of heme oxygenase (HO)-1 in regulation of vascular tone in vivo, we have developed and characterized transgenic (Tg) mice that overexpress HO-1 site specifically in vascular smooth muscle cells (VSMCs). The Tg mice were generated by use of human HO-1 cDNA under the control of SM22-alpha promoter. The HO-1 gene overexpression was demonstrated by Northern blot analysis and coincided with increases in the protein expression in VSMCs and total HO activities. Tg mice exhibited a significant increase in arterial pressure at various ages and displayed impaired nitrovasodilatory responses in isolated aortic segments versus nontransgenic littermates while enhancing their nitric oxide (NO) production. The pressure of Tg mice was unchanged by systemic administration of either N(omega)-nitro-L-arginine or SNP. Furthermore, the isolated aorta in these mice exhibited lesser extents of NO-elicited cGMP elevation via soluble guanylate cyclase (sGC), while exhibiting no notable downregulation of sGC expression. Such impairment of the NO-elicited cGMP increase was restored significantly by tin protoporphyrin IX, an HO inhibitor. On the other hand, 3-(5'-hydroxymethyl-2' furyl)-1-benzyl-indazol (YC-1), an NO-independent activator of sGC, increased cGMP and relaxed aortas from Tg mice to levels comparable with those from nontransgenic mice, which indicates that contents of functionally intact sGC are unlikely to differ between the two systems. These findings suggest that site-specific overexpression of HO-1 in VSMCs suppresses vasodilatory response to NO and thereby leads to an elevation of arterial pressure.

Animals↗
PubMed2001

Evaluation of in vivo release characteristics of protein-loaded biodegradable microspheres in rats and severe combined immunodeficiency disease mice.

The in vivo release characteristics of protein-loaded biodegradable microspheres were examined in normal rats and severe combined immunodeficiency disease (SCID) mice. Bovine-derived superoxide dismutase (bSOD), encapsulated into microspheres comprised of poly(D,L-lactic-co-glycolic acid) and poly(D,L-lactic acid), was used as a model protein. Three types of bSOD-loaded microspheres with different release profiles were subcutaneously administered to normal rats. Anti-bSOD antibodies were first detected at day 9 after the administration of these microspheres, which was independent of their release profiles in vitro. A typical formulation with a sigmoidal release profile was subcutaneously administered to SCID mice. No immunoreaction was observed. The plasma bSOD concentration-time profile, determined by an enzyme-linked immunosorbent assay, well reflected the in vitro release profile of the formulation. The disappearance profile of active bSOD from the administration site also partly corresponded to both profiles. However, the relative bioavailability calculated with a profile on the subcutaneous injection of bSOD solution was 40.7%. These results indicated possible instability of bSOD released gradually at the administration site. The results of the present study using SCID mice would be suitable for discussing the in vitro-in vivo correlation of protein release from microspheres, and useful for designing long-term release formulations of protein drugs.

Animals↗
PubMed2001

Crystal structure of an anticoagulant protein in complex with the Gla domain of factor X.

The gamma-carboxyglutamic acid (Gla) domain of blood coagulation factors is responsible for Ca2+-dependent phospholipid membrane binding. Factor X-binding protein (X-bp), an anticoagulant protein from snake venom, specifically binds to the Gla domain of factor X. The crystal structure of X-bp in complex with the Gla domain peptide of factor X at 2.3-A resolution showed that the anticoagulation is based on the fact that two patches of the Gla domain essential for membrane binding are buried in the complex formation. The Gla domain thus is expected to be a new target of anticoagulant drugs, and X-bp provides a basis for designing them. This structure also provides a membrane-bound model of factor X.

1-Carboxyglutamic Acid↗
PubMed2001

Possible mechanisms regulating ATP- and thimerosal-induced Ca(2+) oscillations in the HSY salivary duct cell line.

The ATP-induced oscillatory changes in cytosolic Ca(2+) concentration ([Ca(2+)](i)) were analysed in HSY cells, a salivary ductal cell line from human parotid, using a fluorescence ratio imaging system. At concentrations higher than 1 microM, ATP caused sinusoidal [Ca(2+)](i) oscillations due to the periodic release and reuptake of Ca(2+) by intracellular Ca(2+) stores. The phorbol ester 4beta-phorbol 12,13-dibutyrate (PDBu) changed the [Ca(2+)](i) oscillations to a single spike. The inhibitory effect of PDBu on the [Ca(2+)](i) signals was reversed by protein kinase C (PKC) inhibitors such as staurosporine and chelerythrine chloride. However, preincubation of the cells with the PKC inhibitors did not affect the pattern of the ATP-induced [Ca(2+)](i) oscillations. The desensitization of the [Ca(2+)](i) response observed during prolonged stimulation with ATP was also not prevented by the PKC inhibitors. Incubation of HSY cells with the sulphydryl reagent thimerosal, which enhances the sensitivity of inositol 1,4,5-trisphosphate (IP(3)) receptors, caused repetitive Ca(2+) release from intracellular Ca(2+) stores resulting in baseline spikes of [Ca(2+)](i). The thimerosal-induced [Ca(2+)](i) oscillations did not change in the presence of PDBu and the phospholipase C inhibitor U73122. Thus, we could not provide evidence that negative feedback by PKC plays a central role in the regulation of ATP-induced [Ca(2+)](i) oscillations. These results suggest that the [Ca(2+)](i) oscillations, at least the baseline spikes, in HSY cells can be generated without stimulating the formation of IP(3).

Adenosine Triphosphate↗