Biomedical subjects

L Bowman

Publications and source records attributed to L Bowman.

At least 55 records · Page 3Linked to original sources

PubMed1995

Unusual cutaneous toxicity following treatment with dactinomycin: a report of two cases.

Dactinomycin-induced cutaneous toxicity is rare in pediatric patients not receiving radiation therapy. We describe dactinomycin-related lesions in the axilla, groin, and central line exit site of two children treated for rhabdomyosarcoma, neither of whom had received radiation treatment. One patient was initially treated with systemic antifungal therapy, and developed recurrent lesions on reexposure to the drug. The other was noted to have mild, diffuse hyperpigmentation. Skin biopsies revealed interface dermatitis with syringometaplasia in both cases. Both children recovered uneventfully within 4 weeks. Recognition of unusual rashes with a characteristic distribution in patients receiving dactinomycin should aid in diagnosis, and help avoid unnecessary therapeutic procedures.

Child↗

PubMed1995

Malignant peripheral nerve sheath tumors: the St. Jude Children's Research Hospital experience.

BACKGROUND: Malignant peripheral nerve sheath tumors (MPNSTs) are uncommon in young patients. To contribute to the understanding of these tumors, we reviewed the records of all patients treated for PNSTs at one institution over a 30-year period. METHODS: We reviewed the records of eight patients treated for benign PNSTs and 28 patients treated for 29 MPNSTs. We focused on the latter group, statistically testing several clinical factors for their significance in affecting survival. RESULTS: Five-year survival in patients with MPNSTs was 39%. The most significant prognostic factor was gross tumor resectability (p = 0.0004). Five-year survival for patients with resectable tumors was 65%, whereas no patient with unresectable disease survived > 25 months. Tumor grade, site, and patient race were also significant factors by univariate analysis but were not significant when adjusted for resectability. CONCLUSION: Gross tumor resection is crucial in treating malignant PNSTs. Supplemental radiation therapy is recommended for positive microscopic margins. More effective treatment is still being sought for unresectable disease.

Adolescent↗

PubMed1995

Properties of lavage material from excised lungs ventilated at different temperatures.

We studied the phospholipid (PL) and protein contents, the PL composition, and some of the surface properties of lavage materials obtained from freshly excised rat lungs and excised lungs which had been ventilated at different temperatures (22, 37, and 42 degrees C). Ventilation (60 breaths/min) was carried out at constant tidal volume with periodic sighs for one hour. Although there is slightly more lavageable PL and protein in lungs ventilated at 22 degrees C than in freshly excised lungs, there is no difference in the PL composition or surface properties of lavage materials from these lungs. However, as the temperature at which lungs are ventilated is increased to 37 degrees and 42 degrees C, there is(are): 1) a reduction in lavage fluid PL, 2) a reduction in the relative amounts of total phosphatidylcholines (PC) and disaturated PC (DSPC), the major surface active component of pulmonary surfactant, 3) an increase in unsaturated PC, and 4) increases in total protein and nonsedimentable protein (100,000 g; 2 hr) in the lavage materials. There are also differences in the surface properties of the lavage materials from lungs ventilated at higher temperatures when compared with freshly excised lungs or lungs ventilated at 22 degrees C, probably as a result of the changes in composition. Maximal surface tension is greater for lavage materials from lungs ventilated at 37 degrees C. For lungs ventilated at 42 degrees C, maximal and minimal surface tension values are increased. These results demonstrate that there are differences in the composition and surface properties of alveolar lavage materials from excised lungs ventilated at different temperatures.

Animals↗

PubMed1994

Computerized drug-use evaluation.

A drug-use evaluation (DUE) of angiotensin-converting-enzyme (ACE) inhibitors by both manual and computerized methods was conducted. Criteria for the use of ACE inhibitors were developed and approved. Fifty patients were randomly selected from 225 clinic outpatients who had begun taking an ACE inhibitor during a six-month period. The clinic medical records of each of the patients were reviewed by a pharmacist to determine compliance with the DUE criteria. At the same time, a computer program queried the computerized medical records of the same patients to evaluate adherence to the criteria. The manual method showed that ACE inhibitor therapy met threshold for two of the six criteria before exceptions were considered and for three criteria after exceptions were considered. Results for only two criteria met threshold when evaluated by the computer; the computer did not consider exceptions. There was good or excellent percent agreement between the manual and computerized methods for four of the six criteria. Kappa values showed that the agreement for five criteria was significant. A computerized method of evaluating drug use performed similarly to manual evaluation, but agreement was best for simply stated criteria.

Angioedema↗

PubMed1994

Changes in alveolar lavage materials and lung microsomal xenobiotic metabolism following exposures to HCl-washed or unwashed crystalline silica.

Intratracheal exposures of rats to crystalline silica washed with HCl to remove iron contaminants have previously been shown to increase lung surfactant phospholipids (PL) and proteins and to alter the pulmonary microsomal cytochrome P450 system. We compared these effects of HCl-washed silica with those produced by exposures to unwashed silica and alumina. Both silica preparations produce increases in lung weights and alveolar lavage PL and proteins, but to different degrees. The increases produced by HCl-washed vs unwashed silica are lung weights, 2.2- vs 1.3-fold; lavage PL, 25.9- vs 3.7-fold; and lavage proteins, 11.1- vs 3.2-fold, respectively. Although the two silica particles increase lung microsomal protein concentrations (expressed per gram lung) by 50-60%, their effects on cytochrome P-450-mediated xenobiotic metabolism are quite different. Exposure to HCl-washed silica leads to a 2.3-fold increase in 7-ethoxyresorufin O-deethylation, a reaction catalyzed by cytochrome P4501A1, and a 0.5- to 0.6-fold reduction in 7-ethoxycoumarin O-deethylation, a reaction which may be catalyzed by cytochrome P-4502B1. Unwashed silica does not alter the metabolism of either xenobiotic when results are expressed per milligram microsomal protein. Administration of alumina produces only minor increases in lung weight and lavage PL and no effect on microsomal xenobiotic metabolism. These results show that the increases in alveolar lavage PL and proteins induced by administration of unwashed silica are exaggerated by 3- to 7-fold if the silica is treated with HCl. Furthermore, exposure to HCl-washed silica results in significant alterations of the lung microsomal cytochrome P450 system, but the unwashed silica has little effect. Although the reason(s) for these different effects is not known, measurements of iron levels and formation of hydroxyl radicals using ESR demonstrate that there is more iron associated with the unwashed than with the HCl-washed silica.

Animals↗

PubMed1994

Primary malignancy of the salivary gland in children.

Seventeen pediatric patients with a major salivary gland malignancy (16 parotid, 1 submaxillary) were reviewed. Eight patients presented with carcinoma. The usual presentation was a mass over the affected gland. Six patients had localized disease, which was treated by excision. This was accomplished by either a total or subtotal parotidectomy or resection of the submaxillary gland. Two patients received adjuvant radiation therapy. All six patients with localized carcinoma are alive, without evidence of disease. Two patients presented with metastatic disease and died of the disease despite treatment with multiagent chemotherapy, and in one case, radiation therapy. Nine patients had rhabdomyosarcoma (RMS). The usual presentation was a mass at the angle of the mandible. Five patients had involvement of one or more cranial nerves, and two had concomitant cervical adenopathy. Eight patients had a biopsy and then were treated according to an existing prospective institutional protocol. The ninth patient initially underwent a superficial parotidectomy. Seven patients received radiation therapy. In one patient, rapid progression of the disease precluded this treatment. Seven patients died of progressive local and distant disease 2 months to 2 years (median, 6 months) from the time of diagnosis. Two patients are alive, without evidence of disease, 3 and 7 years after presentation. We conclude that carcinoma should be managed with complete excision. For RMS of the salivary gland, a biopsy should be performed, and treatment should consist of chemotherapy and radiation therapy.

Adolescent↗

PubMed1994

Effect of enteral feeding with ensure on oral bioavailabilities of ofloxacin and ciprofloxacin.

The relative oral bioavailabilities of ciprofloxacin and ofloxacin when they were coadministered with water or an enteral feeding product (Ensure) were assessed in 13 healthy volunteers. The area under the concentration time curve from time zero to infinity and the maximum concentration of drug in serum for both drugs were reduced by Ensure in comparison with those by water (P < 0.01). However, Ensure reduced the percent relative bioavailability of ciprofloxacin (72% +/- 14%; range, 52 to 96%) significantly more than ofloxacin (90% +/- 8.3%; range, 74 to 105%) (P < 0.005). Coadministration of Ensure significantly diminished ciprofloxacin and ofloxacin absorption, but ciprofloxacin absorption was reduced significantly more than ofloxacin absorption.

Administration, Oral↗

PubMed1994

Phase I study of topotecan for pediatric patients with malignant solid tumors.

PURPOSE: To determine the dose-limiting toxicity and potential efficacy of topotecan in pediatric patients with refractory malignant solid tumors. PATIENTS AND METHODS: In this phase I clinical trial, 27 patients received topotecan 0.75-1.9 mg/m2 by continuous intravenous infusion daily for 3 days. Fifty-three treatment courses were given to these patients. RESULTS: Myelosuppression was the dose-limiting toxicity at levels of 1.3 to 1.9 mg/m2 for 3 days, requiring significant support with transfused packed RBCs and platelets. Myelosuppression was variable in severity at the 1.0-mg/m2 dosage level; thus, additional patients were treated with this dosage, followed by human recombinant granulocyte-colony stimulating factor (G-CSF). Other toxicities were not significant. One patient with neuroblastoma had a complete response that lasted for 8 months. Stable disease activity was recorded for other patients with neuroblastoma, rhabdomyosarcoma, and islet cell carcinoma. Pharmacokinetic studies showed that topotecan plasma concentrations ranged from 1.6 to 7.5 ng/mL during infusions of 1.0 mg/m2/d, and that there was a biphasic plasma distribution with a mean terminal half-life of 2.9 +2- 1.0 hours. CONCLUSION: Topotecan is a promising anticancer agent that deserves phase II testing in pediatric solid tumors. We recommend that pediatric phase II topotecan trials use 1.0 mg/m2/d for 3 days as a constant intravenous infusion, followed by G-CSF for 14 days, and that these treatment courses be repeated every 21 days.

Adolescent↗

PubMed1994

Phase I study of oral etoposide in children with refractory solid tumors.

PURPOSE: To determine the maximum-tolerated dose (MTD), dose-limiting toxicity, and plasma concentrations of orally administered etoposide (VP-16) in pediatric oncology patients. PATIENTS AND METHODS: In a phase I study, 20 children with refractory solid tumors received oral VP-16 (the intravenous preparation diluted with sodium chloride) three times daily for 21 days. Daily dose levels studied were 50 mg/m2 (n = 5), 60 mg/m2 (n = 7), and 75 mg/m2 (n = 8). VP-16 concentrations were measured in blood samples collected on days 1, 7, 14, and 21. RESULTS: Grade 3 to 4 thrombocytopenia and/or neutropenia causing interruption of the 21-day course or persisting for more than 7 days after the last day of chemotherapy was seen at all dose levels, but was not dose-limiting. One patient treated at the 50-mg/m2 daily dose died of sepsis. At the 75-mg/m2 dose level, diarrhea was dose-limiting. Estimated plasma VP-16 concentrations were greater than 1 micrograms/mL for median periods of 9.4, 15.4, and 13.5 hours per day at daily doses of 50, 60, and 75 mg/m2, respectively. Responses were observed in seven of 14 patients who received at least one additional course of etoposide after a rest period of 7 days. There was one complete and two objective responses. Four patients were considered to have stable disease. CONCLUSION: The intravenous preparation of VP-16 administered orally appears to be well tolerated by heavily pretreated pediatric patients. On the three-times daily, 21-day schedule, a daily dose of 75 mg/m2 exceeds the MTD, with diarrhea as the dose-limiting toxicity. The recommended dose for oral etoposide is 60 mg/m2/d administered every 8 hours.

Administration, Oral↗

PubMed1994

Incidence of adverse drug reactions in adult medical inpatients.

This study was a prospective observational study of ADR occurrence and evaluation in adult internal medicine inpatients conducted over a 120-day period. Clinical pharmacists screened for ADRs at a county hospital in Indianapolis, IN. Patient information was reviewed on admission, every four days during hospitalization, and at discharge. ADRs occurring after hospital admission were assessed for causality, severity, pharmacological type (i.e., augmented pharmacology versus idiosyncratic reaction) and affected organ system. Nurse and pharmacist reports, incident reports, physician consults, patient transfers to critical care units, and serum drug concentration reports were additional means of ADR identification. Overall, 23.1% of patients experienced an ADR while 2.6% of the 11,702 drug exposures resulted in an ADR. Patients aged greater than 65 years (29.6% vs. 20.5% for younger patients) and females (26.2% vs. 20% for males) were at higher risk for ADR development (p < 0.05). Length of hospital stay was longer (13.3 days vs. 6.7 days; p < 0.05) and drug exposures more frequent for patients experiencing ADRs (p < 0.001). Furosemide elicited the most ADRs with 36 in 244 patient exposures (14.7%). Diltiazem, enalapril, heparin, trimterene/hydrochlorothiazide combination and captopril were also frequently implicated. ADRs were classified as mild (35.9%), moderate (52.6%), and severe (10.2%). Organ systems most commonly affected were the metabolic/hematologic (32.9%), gastrointestinal (17.8%), genitourinary (11.8%), and cardiovascular (10.5%). Over 30% of events were idiosyncratic reactions. ADR incidence was consistent with previous literature. Many frequently implicated medications were newer agents and the severity of events was less than previously reported.

Adult↗

PubMed1993

A phase I study of ifosfamide with Mesna given daily for 3 consecutive days to children with malignant solid tumors.

BACKGROUND: The authors conducted a Phase I dose escalation trial of ifosfamide given daily for 3 consecutive days to 29 children with malignant solid tumors. Twenty-eight of these children had received prior chemotherapy. METHODS: Patients were assigned to dosage cohorts separately on the basis of prior exposure to the platinum alkylating agents cisplatin or carboplatin (n = 20) or the absence of such exposure (n = 9). At least three patients in each category were treated at a starting dosage of 2133 mg/m2/d for 3 days. This dosage represented 80% of the total dose delivered in the prior study of ifosfamide given daily over 5 days with dosage escalation of 20% in subsequent cohorts. RESULTS: Myelosuppression was dose-limiting at the second dosage level (2560 mg/m2/d) for patients previously treated with platinum and at the third dosage level (3072 mg/m2/d) for those not previously treated with platinum. Dose-limiting neurotoxicity was seen at 2560 mg/m2/d for the former group, but was not encountered in the latter group. CONCLUSIONS: Delivery of ifosfamide daily for 3 days is feasible and safe at recommended dosages of 2133 mg/m2/d for children with prior exposure to platinum and 3000 mg/m2/d for those without prior exposure.

Adolescent↗

PubMed1993

Alterations in alveolar type II cell metabolism induced by tetrandrine and other alkaloids.

Tetrandrine (TT) and other bisbenzylisoquinoline alkaloids have been used in China as a treatment for fibrotic lung diseases. Because of their potential use as pulmonary therapeutic agents, we studied the effects of some of these compounds on energy metabolism in isolated rat alveolar type II cells, i.e., cells which play a critical role in maintaining normal lung function. Incubation of type II cells with most of the alkaloids produces a reduction in cellular ATP content. However, there is no effect of the alkaloids on cellular oxygen consumption. All of the alkaloids which produce reductions in cell ATP levels cause increases in internal calcium levels of type II cells. Incubation of the cells with the calcium ionophore, 4-bromo A-23187, leads to increased amounts of intracellular calcium and reductions in ATP levels, but has no effect on oxygen consumption. Exposure of isolated lung mitochondria to calcium produces a concentration-dependent reduction in ATP synthesis with no effect on mitochondrial oxygen consumption. Direct exposure of mitochondria to TT has no effect on ATP synthesis. These results are consistent with the notion that the alkaloids produce an increase in type II cell internal calcium levels which, in turn, leads to reduced rates of mitochondrial ATP synthesis.

Adenosine Triphosphate↗

PubMed1993

Determination of a gentamicin loading dose in neonates and infants.

The use of gentamicin as a co-therapy for the treatment of sepsis is common practice in neonates and infants. Gentamicin dosing guidelines have been developed over the past 20 years to accommodate a slower renal elimination rate of gentamicin in the neonatal population. Recently, it has become evident that early attainment of serum gentamicin concentrations > or = 5 micrograms/ml results in a greater therapeutic outcome in septic adult patients. As neonatal immunity is immature and aminoglycosides have an extended elimination half-life in the very young population, reassessment of the initial gentamicin dose has become necessary. Using retrospective data, we determined the amount of gentamicin necessary to effectively "load" a group of neonatal/pediatric patients to achieve initial serum concentrations of 6 or 8 micrograms/ml. One hundred sixty-six patients less than 12 months postnatal age were studied. The mean initial dose delivered was 2.41 mg/kg. Younger patients demonstrated larger gentamicin apparent volumes of distribution and slower elimination half-lives than did older patients. Initial serum gentamicin concentrations calculated from steady-state pharmacokinetic parameters were significantly lower than those seen at steady state. In order to achieve initial serum gentamicin concentrations > 6 micrograms/ml an initial dose of 3 mg/kg would be necessary in the group of patients studied. Younger patients (< or = 34 weeks gestational age) would likely require 4 mg/kg as an initial dose.

Aging↗

PubMed1993

Alterations in the pulmonary microsomal cytochrome P-450 system after exposure of rats to silica.

Because some evidence indicates that there is an increased incidence of lung cancer in silicosis, we studied the effects of exposing rats to silica on the pulmonary microsomal cytochrome P-450 system. Rats were exposed to silica by intratracheal administration, lung microsomes were obtained from untreated and silica-treated animals, and the amount of microsomal tissue, the level of total cytochromes P-450 (all isozymes), the activity of NADPH cytochrome P-450 reductase, the metabolism of two xenobiotics, and the relative amounts of cytochrome P-4502B1 and P-4501A1 were measured. Lungs from silica-treated rats were almost 2-fold heavier and contained more than 10 times more alveolar phospholipids than lungs from untreated animals, indicating that acute silicosis had been produced. In lungs from silica-treated animals, the concentration of microsomal tissue, expressed as milligrams of microsomal protein per gram of lung, was increased by more than 2-fold, and total microsomal protein content was increased by almost 5-fold relative to untreated animals. When expressed as activity or amount per milligram of protein, the microsomal concentrations of NADPH cytochrome P-450 reductase, total cytochromes P-450, 7-ethoxycoumarin (EC)-0-deethylase, and cytochrome P-4502B1 are reduced by approximately 50% in silica-treated rats. However, when expressed as total activity or amount in the lungs, all are increased by approximately 1.5- to 2.5-fold in silica-treated lungs. On the other hand, total lung 7-ethoxyresorufin (ER)-0-deethylase activity and cytochrome P-4501A1 are increased by 4- to 5-fold in silica-treated lungs.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1992

Sarcomas of the flexor fossae in children: is amputation necessary?

Successful management of sarcomas of the extremities in children implies not only achievement of local control but also satisfactory function and maintenance of the growth potential. The popliteal and antecubital fossae, because of their complex neurovascular anatomy, all of which is essential, make resection with satisfactory margins difficult. We reviewed our experience with 14 patients (3 to 20 years old; median, 13 years) with soft tissue sarcomas arising in the popliteal (11 patients) or antecubital (3 patients) fossae. There were four rhabdomyosarcomas (3 alveolar, 1 embryonal) and 10 other sarcomas, the most frequent being synovial sarcoma (5 patients). Chemotherapy was given to all patients with rhabdomyosarcomas. The one patient presenting with metastatic disease was treated, after biopsy of the primary, by chemotherapy and radiation and survived 21 months. In three patients, the primary management was an above-the-knee amputation and two of three survived (3 and 43 months). In 10 patients a wide local excision of the primary tumor was performed. Radiation therapy was administered to five, either as external beam (3 patients) or as brachytherapy (2 patients). In this group, there were no local recurrences. Four patients remain free of disease (4 months to 18 years) and one developed pulmonary metastasis. Among the five non-irradiated patients, three developed local recurrences, requiring above-the-knee amputation for disease. The fourth patient relapsed in the lung and only one of the five is free of disease at 36 months. Of the 8 patients not treated with amputation, one acquired a leg length discrepancy, which required correction, and one has a minimal extension deficit of the knee.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1991

Primary extracranial neuroblastoma with central nervous system metastases characterization by clinicopathologic findings and neuroimaging.

The authors report the clinicopathologic and neuroimaging findings in ten children with primary abdominal or thoracic neuroblastoma who relapsed in the central nervous system (CNS) without evidence of concurrent intracranial extension from adjacent bone, dura, or dural sinus metastases. At diagnosis, the patients ranged in age from 0.3 to 4.5 years (median, 2 years). Their times to CNS relapse ranged from 2 to 34 months from diagnosis. In seven patients the relapse occurred from 1 to 14 months after elective discontinuation of therapy. In four patients, the CNS relapse was the primary (isolated) adverse event. Four patients could not be treated at the time of relapse, and they died within 7 days of progressive CNS disease. In the remaining group, craniospinal irradiation with or without administration of a platinum compound and an epipodophyllotoxin caused complete CNS remissions lasting 4, 5, 16, and 62+ months. Neuroimaging and autopsy findings indicated that cerebrospinal fluid is the major pathway for neuraxis dissemination by neuroblastoma cells. There was no evidence of dural penetration in any patient. The possibility of relapse in the neuraxis should be considered for any patient with neuroblastoma who had neurologic deterioration. A combination of craniospinal radiation and administration of a platinum compound and an epipodophyllotoxin will induce complete responses in some patients with neuraxis involvement by neuroblastoma, but the risk of subsequent failure outside the CNS remains high.

Abdominal Neoplasms↗

PubMed1991

Indications for computed tomography in children with blunt abdominal trauma.

This investigation was undertaken to identify clinical variables, alone or in combination, that could be used to assign children to high- and low-risk categories for intra-abdominal injury following blunt trauma. Six hundred consecutive children who were examined with computed tomography (CT) following blunt trauma were enrolled. Complete data sets were available on 375 children. Stepwise logistic regression was used to identify predictor variables for the presence of abdominal injury. There were 174 children with abdominal injury detected by CT. Of these, 95 were classified as having significant injury. Indicators associated with significantly higher risk of abdominal injury included the following: more than three clinical indications given (odds likelihood ratio [OLR] = 4.60, 95% confidence interval [95% Cl] = 2.29, 9.21, p less than 0.001); gross hematuria (OLR = 5.80, 95% Cl = 2.51, 13.4, p less than 0.001); lap belt injury (OLR = 12.2, 95% Cl = 2.22, 66.8, p less than 0.01); assault or abuse as the mechanism of injury (OLR = 5.08, 95% Cl = 1.07, 24.2, p less than 0.05); abdominal tenderness (OLR = 2.73, 95% Cl = 1.296, 5.82, p less than 0.01); and Trauma Score less than or equal to 12 (OLR = 2.27, 95% Cl = 1.006, 5.13, p less than 0.01). No child with asymptomatic hematuria (n = 56), regardless of grade or neurologic impairment in the absence of abdominal findings (n = 15), had an abnormal CT examination. These data are useful as an adjunct to clinical judgment in triage when the availability of CT equipment is limited or there are competing extra-abdominal injuries.

Abdominal Injuries↗

PubMed1991

Primary action of endothelin on Ca release in bovine coronary artery smooth muscle cells.

Intracellular free Ca concentrations (Cai) were determined by fura-2 microfluorometry in single freshly dispersed cells to differentiate endothelin (ET)-induced Ca release from Ca influx through voltage-gated Ca channels (VGCC). In physiological solution ET (10(-8) M) significantly (P less than 0.05) increased Cai 23 +/- 3% (+/- SE) above baseline; this increase was not significantly attenuated by 2 x 10(-4) M lanthanum, a blocker of VGCC, or Ca-free solution. When the sarcoplasmic reticulum was depleted of Ca by prolonged treatment with 5 x 10(-3) M caffeine, depolarization with 80 mM K (80K; or 30K) plus ET did not increase Cai above that induced by 80K (or 30K) in caffeine alone. In contrast, 10(-6) M BAY K 8644, instead of ET in the protocol, significantly (P less than 0.05) increased Cai above that induced by 80K (or 30K). ET released Ca from the caffeine-sensitive internal store but was not rapid and transient like caffeine-induced release, which elicited a peak Cai increase in less than 1 min; instead, release was more gradual and prolonged with Cai peaking in greater than 2 min, thus resembling the response to 10(-5) M ryanodine. With two ET exposures, either a transient nonrepeatable increase in Cai or a delayed, but sustained, increase in Cai resulted, similar to the response to ryanodine. These data indicate that in freshly dispersed bovine cells the predominant mechanism by which ET increases Cai is release of Ca from the sarcoplasmic reticulum; if any increase in L-type voltage-gated Ca influx occurred, it was minimal and matched by efflux.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗