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S Gauthier

Publications and source records attributed to S Gauthier.

At least 37 records · Page 2Linked to original sources
PubMed2001

Outcome measures for probable vascular dementia and Alzheimer's disease with cerebrovascular disease.

Vascular dementia (VaD) can be defined as dementia associated with cerebrovascular disease (CVD), and accounts for a large proportion of all dementia cases. There is substantial overlap in the clinical symptomatology, pathophysiology and neurochemical mechanisms in VaD compared with Alzheimer's disease, suggesting that an effective treatment for Alzheimer's disease may also offer benefit as a symptomatic treatment in VaD. However, there are currently no explicit guidelines for conducting clinical pharmacotherapy trials in VaD patients. Two important requirements for assessing therapeutic benefits in such trials are 1) the inclusion of appropriate patients and 2) the use of appropriate outcome measures. Debate on the precise definition of VaD in relation to patient selection criteria continues, but many of the recommendations for outcome measures in Alzheimer's disease are already applicable to VaD. There is consensus that cognitive and global function measures, and assessments of abilities to perform activities of daily living (ADL) must be included as part of the optimal assessment battery in VaD trials. A measure of reduced behavioural symptoms with associated reductions in demands on caregivers would also be desirable. However, care must be taken in extrapolating Alzheimer's disease-specific evaluations to VaD, in that important differences in specific domains affected and characteristics of disease course must be taken into account. Between them, measures such as the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog; perhaps with supplemental tests of attention and other frontal lobe functions), evaluations of clinical global impression of change and a functional assessment addressing instrumental as well as basic ADL, e.g. Disability Assessment in Dementia (DAD) scale, should provide a good overall description of VaD-related deficits and sufficient appraisal of treatment effects. The Neuropsychiatric Inventory has also been shown to have good potential utility for measuring behavioural alterations in VaD. These and other assessments are reviewed to provide a balanced and realistic view of the type of treatment outcomes that can be expected in VaD pharmacotherapy trials, and to address the best ways of measuring these outcomes.

Alzheimer Disease↗
PubMed2000

The Nramp2/DMT1 iron transporter is induced in the duodenum of microcytic anemia mk mice but is not properly targeted to the intestinal brush border.

Microcytic anemia (mk) mice and Belgrade (b) rats are severely iron deficient because of impaired intestinal iron absorption and defective iron metabolism in peripheral tissues. Both animals carry a glycine to arginine substitution at position 185 in the iron transporter known as Nramp2/DMT1 (divalent metal transporter 1). DMT1 messenger RNA (mRNA) and protein expression has been examined in the gastrointestinal tract of mk mice. Northern blot analysis indicates that, by comparison to mk/+ heterozygotes, mk/mk homozygotes show a dramatic increase in the level of DMT1 mRNA in the duodenum. This increase in RNA expression is paralleled by a concomitant increase of the 100-kd DMT1 isoform I protein expression in the duodenum. Immunohistochemical analyses show that, as for normal mice on a low-iron diet, DMT1 expression in enterocytes of mk/mk mice is restricted to the duodenum. However, and in contrast to normal enterocytes, little if any expression of DMT1 is seen at the apical membrane in mk/mk mice. These results suggest that the G185R mutation, which was shown to impair the transport properties of DMT1, also affects the membrane targeting of the protein in mk/mk enterocytes. This loss of function of DMT1 is paralleled by a dramatic increase in expression of the defective protein in mk/mk mice. This is consistent with a feedback regulation of DMT1 expression by iron stores. (Blood. 2000;96:3964-3970)

Alleles↗
PubMed2000

Isolation and purification of serum and interfacial peptides of a trypsinolyzed beta-lactoglobulin oil-in-water emulsion.

Information on the conformation of proteins adsorbed to an oil-water interface is usually determined by following the time course of enzymatic hydrolysis of the protein in an oil-in-water emulsion. Unlike previous works reported in the literature, the research presented in this paper provides information on which peptides are actually in contact with the lipid bilayer (interfacial peptides) and those segments that project into the aqueous phase (serum peptides). In order to achieve this classification of peptides, we present a method to separate serum peptides from interfacial peptides by initial centrifugation steps followed by reversed-phase high-performance liquid chromatography. The effectiveness of the method was ascertained by performing proteolysis on beta-lactoglobulin adsorbed to an oil-water interface in a soybean oil-water emulsion. It was found that more peptides are qualitatively and quantitatively found adsorbed to the oil-water interface as compared to peptides released into the serum.

Adsorption↗
PubMed2000

Long-term inhibitory effect of the orally active and pure antiestrogen EM-800 on the growth of human breast cancer xenografts in nude mice.

The antiproliferative effect of the new antiestrogen EM-800 has been studied during 40 weeks of treatment on human breast carcinoma ZR-75-1 xenografts in ovariectomized nude mice supplemented with estrone (0.5 microg, s.c. daily). At the daily 50 microg (approximately 2.5 mg/kg) oral dose, EM-800 caused a complete inhibition of the 680% stimulatory effect of estrone on the growth of the ZR-75-1 human breast cancer xenografts. Complete response, defined as the complete disappearance of the tumors, was observed in 41% of tumors following treatment with the 50 microg dose of the antiestrogen, while a value of 26% was found in ovariectomized animals. The proportion of tumors showing progression at the end of 40 weeks of treatment decreased from 94% in the estrone-supplemented animals to 62%, 61% and 19% in the animals receiving the 5 microg, 20 microg and 50 microg daily doses of the antiestrogen, respectively. None of the tumors that showed a complete or a partial response progressed at later time intervals. The 50 microg daily dose of EM-800 nearly completely (93%) or completely (28% below the value in ovariectomized animals) reversed the stimulatory effect of estrone on uterine and vaginal weight, respectively. The disappearance of 41% of tumors in the group of animals that received the 50 microg daily dose of EM-800 indicates that the antiestrogen induces cell death or apoptosis in ZR-75-1 human breast cancer cells and that its action is cytotoxic and not only cytostatic.

Administration, Oral↗
PubMed2000

Rivastigmine for Alzheimer's disease: Canadian interpretation of intermediate outcome measures and cost implications.

BACKGROUND: Clinical studies have shown that patients with Alzheimer's disease (AD) who are treated with rivastigmine have statistically significantly better scores on 5 scales used to assess AD than control patients receiving placebo. However, the clinical meaning and cost implications of these differences are not clear. OBJECTIVE: The purpose of this study was to assess the clinical meaning and cost implications of statistically significant results obtained in clinical trials of rivastigmine for the treatment of AD. Potential cost implications for the health care system, caregivers, and society are considered. METHODS: Data on clinical effects of rivastigmine were obtained from published North American and European clinical studies of patients with mild to moderately severe AD receiving rivastigmine 6 to 12 mg/d (n = 828) or placebo (n = 647). Differences in scores on the Alzheimer's Disease Assessment Scale-Cognitive Function, Clinician's Interview-Based Impression of Change with both clinical and caregiver information considered, Progressive Deterioration Scale, Mini-Mental State Examination (MMSE), and Global Deterioration Scale were assessed. A convenience panel of 9 Canadian specialists experienced in the treatment of AD provided their opinions on the clinical importance of the trial results. Chart review was performed to identify specific behaviors that improved, and cost implications of improvements were assessed. RESULTS: The panel determined that statistically significant differences in scores on all scales except the MMSE were likely associated with functional or cognitive differences that were clinically relevant for patients, reflecting stabilization that would have beneficial consequences for caregivers and health care resource use. Subsequent chart review showed that improvement on specific scale items confirmed the physician panel's opinion. Analysis of possible cost implications to society indicated that medication expenditures would be offset largely by delays in the need for paid home care and institutionalization, positive effects on caregiver health, and less time lost from work for the caregiver. CONCLUSIONS: From the perspective of a Canadian specialist panel, rivastigmine treatment for AD produces clinically relevant effects for patients that are beneficial to caregivers. These effects suggest decreased use of caregiver resources and delays in the need for institutionalization, both of which reduce societal costs.

Aged↗
PubMed2000

Alteration of expression levels of neuronal nitric oxide synthase and haem oxygenase-2 messenger RNA in the hippocampi and cortices of young adult and aged cognitively unimpaired and impaired Long-Evans rats.

Neuronal nitric oxide synthase and haem oxygenase-2 are postulated to be important enzymes involved in neuronal transmission and modulation of free radical levels in neurons. Hippocampal and cortical neuronal nitric oxide synthase and haem oxygenase-2 expressions were compared in young adult (6 months) and aged (24-26 months) Long-Evans rats. Aged rats were assigned as either cognitively unimpaired or impaired based on their performances in the Morris water maze behavioural task. In situ hybridization revealed increased neuronal nitric oxide synthase messenger RNA levels in selected regions of the hippocampi and cortices of aged rats. Moreover, aged cognitively impaired animals showed significantly higher neuronal nitric oxide synthase messenger RNA expression than aged cognitively unimpaired animals in several brain regions. For haem oxygenase-2 mRNA expressions, both young and aged cognitively impaired rats showed increased expressions in hippocampi compared with aged cognitively unimpaired rats, while no difference was found in cortices between all three animal groups. The increase in neuronal nitric oxide synthase messenger RNA expression levels in the aged animals may be related to increased free radical production occurring in ageing. Alternatively, elevated neuronal nitric oxide synthase and haem oxygenase-2 messenger RNA expressions may represent compensatory responses to oxidative stress and age-related changes in neuronal functions. Regarding cognitive status, aged cognitively impaired rats showed significant spatial memory deficits relative to young and aged cognitively unimpaired rats. Our data suggest a correlation between age-related cognitive impairment and change in messenger RNA expressions for the neuronal nitric oxide synthase and haem oxygenase-2 systems in brain areas implicated in learning and memory processes.

Aging↗
PubMed2000

Verapamil increases the survival of patients with anthracycline-resistant metastatic breast carcinoma.

BACKGROUND: Verapamil (VER), a potent calcium channel blocker, has been found to overcome P-gp-mediated multi-drug resistance (MDR) and to increase sensitivity to cytotoxic anticancer drugs in refractory myeloma and non-Hodgkin lymphoma. The value of VER for treating solid tumors is still a matter for debate. PATIENTS AND METHODS: We performed a prospective study in 99 patients with anthracycline-resistant metastatic breast carcinoma (MBC), to assess the clinical effect of oral VER given in association with chemotherapy. Instead of retreating patients with anthracycline, we used a partially noncross-resistant regimen (VF), combining vindesine (VDS) and 5-fluorouracil given as a continuous infusion (5-FU CI). Patients were randomly assigned to two cohorts. One cohort (47 patients) was treated in 28-day cycles, each involving the administration of VDS (3 mg/m2 i.v. bolus on days 1 and 10) and 5-FU CI, (400 mg/m2/day i.v. from day 1 to day 10). The other cohort (52 patients) received the same VDS and 5-FU treatment and an additional oral VER treatment (240 mg/day divided in 2 doses), from day 1 to day 28 of each cycle. Patients were treated until progression. RESULTS: The treatment was well tolerated and no side effects that could be attributed to VER were detected. Patients treated with VER had longer overall survival (OS) (median OS: 323 vs. 209 days, P = 0.036) and a higher response rate (27% vs. 11%, P = 0.04) than those not given VER. Progression-free survival (PFS) was also longer but the difference was not statistically significant (median PFS: 4.6 and 2.7 months for the VER and non-VER groups respectively, P = 0.6). CONCLUSIONS: This clinical trial demonstrates that a chemosensitizer, such as VER, can increase the survival of MBC patients with acquired anthracycline resistance.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

The diagnosis of "mixed" dementia in the Consortium for the Investigation of Vascular Impairment of Cognition (CIVIC).

If vascular risk factors are risk for Alzheimer's disease (AD), and if "pure" vascular dementia (VaD) is less common than has been thought, what do we make of the diagnosis of mixed dementia? We report characteristics of those with mixed dementia in a prospective, seven center, clinic-based Canadian study. Of 1,008 patients, 372 were diagnosed with AD, 149 with vascular cognitive impairment (VCI) including 76 with mixed AD/VaD, and 82 with other types of dementia. The mean age of patients with mixed AD/VaD was 78.0 +/- 7.6 years; 49% were female. These proportions differed significantly between dementia diagnosis subgroup (p < 0.001) showing a trend which is evident in all comparisons--AD/VaD patients fall in between AD and VaD. Vascular risk factors were present significantly more often in mixed AD/VaD than in AD (p < 0.001). More mixed AD/VaD (20%) than AD patients (4%) had focal signs, compared with 38% of those with vascular dementia and 12% with other types of dementia. Between the initial clinical diagnosis and the final diagnosis (which utilized neuroimaging and neuropsychological data) AD/VaD was the least stable diagnosis. Neuroimaging of ischemic lesions was the most common reason for reassignment from AD to the mixed AD/VaD diagnosis (17 cases). These data suggest that an operational definition of mixed AD/VaD can be proposed on presentation and clinical/radiographic findings, but indifferent to vascular risk factors. The concept of mixed dementia should be extended to include vascular dementia in combination with dementias, other than Alzheimer's disease.

Aged↗
PubMed2000

Metrifonate enhances the ability of Alzheimer's disease patients to initiate, organize, and execute instrumental and basic activities of daily living.

The objective of this analysis was to evaluate comprehensively the efficacy of metrifonate, a long-acting acetylcholinesterase inhibitor, in improving the ability of mild-to-moderate Alzheimer's disease (AD) patients to perform activities of daily living (ADLs). Alzheimer's disease patients with Mini-Mental State Examination scores of 10 to 26 were enrolled in three 26-week trials to receive once-daily placebo (n = 430) or metrifonate 30 to 60 mg (by weight, n = 650) or 60/80 mg (by weight, n = 197). Metrifonate efficacy was assessed using the Disability Assessment for Dementia scale. Data from the three studies were pooled and analyzed retrospectively. The intent-to-treat analysis (last observation carried forward) at 26 weeks demonstrated that metrifonate significantly improved the ability of AD patients to perform ADLs when compared with placebo (30-60 mg dose, delta = 3.03; P = .002; 60/80 mg dose, delta = 5.25; P = .0002). Metrifonate significantly improved the ability of the AD patients to perform instrumental ADLs, those abilities typically lost first during the disease process (30-60 mg dose, delta = 3.88, P = .002; 60/80 mg dose, delta = 5.79, P = .003). Metrifonate also tended to improve, relative to placebo, the ability of AD patients to use three levels of executive skills when performing ADLs: initiation (30-60 mg dose, delta = 3.45, P = .001; 60/80 mg dose, delta = 5.44, P = .003), planning/organization (30-60 mg dose, delta = 4.50, P = .004; 60/80 mg dose, delta = 4.89, P = .014), and effective execution (30-60 mg dose, delta = 1.80, P = .076; 60/80 mg dose, delta = 4.06, P = .030). These results indicate that metrifonate has a beneficial effect on the ADLs in mild-to-moderate AD patients.

Activities of Daily Living↗
PubMed2000

Androgen receptor antagonists (antiandrogens): structure-activity relationships.

Prostate cancer, acne, seborrhea, hirsutism, and androgenic alopecia are well recognized to depend upon an excess or increased sensitivity to androgens or to be at least sensitive to androgens. It thus seems logical to use antiandrogens as therapeutic agents to prevent androgens from binding to the androgen receptor. The two predominant naturally occurring androgens are testosterone (T) and dihydrotestosterone (DHT). DHT is the more potent androgen in vivo and in vitro. All androgen-responsive genes are activated by androgen receptor (AR) bound to either T or DHT and it is believed that AR is more transcriptionally active when bound to DHT than T. The two classes of antiandrogens, presently available, are the steroidal derivatives, all of which possess mixed agonistic and antagonistic activities, and the pure non-steroidal antiandrogens of the class of flutamide and its derivatives. The intrinsic androgenic, estrogenic and glucocorticoid activities of steroidal derivatives have limited their use in the treatment of prostate cancer. The non-steroidal flutamide and its derivatives display pure antiandrogenic activity, without exerting agonistic or any other hormonal activity. Flutamide (89) and its derivatives, Casodex (108) and Anandron (114), are highly effective in the treatment of prostate cancer. The combination of flutamide and Anandron with castration has shown prolongation of life in prostate cancer. Furthermore, combined androgen blockade in association with radical prostatectomy or radiotherapy are very effective in the treatment of localized prostate cancer. Such an approach certainly raises the hope of a further improvement in prostate cancer therapy. However, all antiandrogens, developed so-far display moderate affinity for the androgen receptor, and thus moderate efficacy in vitro and in vivo. There is thus a need for next-generation antiandrogens, which could display an equal or even higher affinity for AR compared to the natural androgens, and at the same time maintain its pure antiandrogenic activity, and thus providing improved androgen blockade using possibly antiandrogens alone.

Androgen Antagonists↗
PubMed1999

The recognition, assessment and management of dementing disorders: conclusions from the Canadian Consensus Conference on Dementia.

OBJECTIVE: To develop evidence based consensus statements on which to build clinical practice guidelines for primary care physicians toward the recognition, assessment and management of dementing disorders and to disseminate and evaluate the impact of these statements and guidelines built on these statements. OPTIONS: Structured approach to assessment, including recommended laboratory tests, choices for neuroimaging and referral, management of complications (especially behavioural problems and depression) and use of cognitive enhancing agents. POTENTIAL OUTCOMES: Consistent and improved clinical care of persons with dementia; cost containment by more selective use of laboratory investigations; neuroimaging and referrals; and appropriate use of cognitive enhancing agents. EVIDENCE: Authors of each background paper were entrusted to perform a literature search, discover additional relevant material, including references cited in retrieved articles, consult with other experts in the field and then synthesize information. Standard rules of evidence were applied. Based on this evidence, consensus statements were developed by a group of experts, guided by a steering committee of 8 individuals, from the areas of Neurology, Geriatric Medicine, Psychiatry, Family Medicine, Preventive Health Care and Health Care Systems. VALUES: Recommendations have been developed with particular attention to the context of primary care, and are intended to support family physicians in their ongoing assessment and care of patients with dementia. BENEFITS HARM AND COSTS: Potential for improved clinical care of people with dementia. A dissemination and evaluation strategy will attempt to measure the impact of the recommendations. RECOMMENDATIONS: Forty-eight recommendations are offered that address the following aspects of dementia care: early recognition; importance of careful history and examination in making a positive diagnosis; essential laboratory tests; rules for neuroimaging and referral; disclosure of diagnosis; importance of monitoring and providing support to caregivers; cultural aspects; detection and treatment of depression; observation and management of behavioural disturbances; detection and reporting of unsafe motor vehicle driving; genetic factors and opportunities for preventing dementia; pharmacological treatment with particular emphasis on cognitive enhancing agents. VALIDATION: Four other sets of consensus statement or guidelines have been published recently. These recommendations are generally congruent with our own consensus statements. The consensus statements have been endorsed by relevant bodies in Canada.

Automobile Driving↗
PubMed1999

Efficacy and safety of rivastigmine in patients with Alzheimer's disease: international randomised controlled trial.

OBJECTIVES: To assess the effects of rivastigmine on the core domains of Alzheimer's disease. DESIGN: Prospective, randomised, multicentre, double blind, placebo controlled, parallel group trial. Patients received either placebo, 1-4 mg/day (lower dose) rivastigmine, or 6-12 mg/day (higher dose) rivastigmine. Doses were increased in one of two fixed dose ranges (1-4 mg/day or 6-12 mg/day) over the first 12 weeks with a subsequent assessment period of 14 weeks. SETTING: 45 centres in Europe and North America. PARTICIPANTS: 725 patients with mild to moderately severe probable Alzheimer's disease diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, and the criteria of the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association. OUTCOME MEASURES: Cognitive subscale of the Alzheimer's disease assessment scale, rating on the clinician interview based impression of change incorporating caregiver information scale, and the progressive deterioration scale. RESULTS: At the end of the study cognitive function had deteriorated among those in the placebo group. Scores on the Alzheimer's disease assessment scale improved in patients in the higher dose group when compared with patients taking placebo (P<0.05). Significantly more patients in the higher dose group had improved by 4 points or more than had improved in the placebo group (24% (57/242) v 16% (39/238)). Global function as rated by the clinician interview scale had significantly improved among those in the higher dose group compared with those taking placebo (P<0.001), and significantly more patients in the higher dose group showed improvement than did in the placebo group (37% (80/219) v 20% (46/230)). Mean scores on the progressive deterioration scale improved from baseline in patients in the higher dose group but fell in the placebo group. Adverse events were predominantly gastrointestinal, of mild to moderate severity, transient, and occurred mainly during escalation of the dose. 23% (55/242) of those in the higher dose group, 7% (18/242) of those in the lower dose group, and 7% (16/239) of those in the placebo group discontinued treatment because of adverse events. CONCLUSIONS: Rivastigmine is well tolerated and effective. It improves cognition, participation in activities of daily living, and global evaluation ratings in patients with mild to moderately severe Alzheimer's disease. This is the first treatment to show compelling evidence of efficacy in a predominantly European population.

Activities of Daily Living↗
PubMed1999

The iron transport protein NRAMP2 is an integral membrane glycoprotein that colocalizes with transferrin in recycling endosomes.

The natural resistance associated macrophage protein (Nramp) gene family is composed of two members in mammals, Nramp1 and Nramp2. Nramp1 is expressed primarily in macrophages and mutations at this locus cause susceptibility to infectious diseases. Nramp2 has a much broader range of tissue expression and mutations at Nramp2 result in iron deficiency, indicating a role for Nramp2 in iron metabolism. To get further insight into the function and mechanism of action of Nramp proteins, we have generated isoform specific anti-Nramp1 and anti-Nramp2 antisera. Immunoblotting experiments indicate that Nramp2 is present in a number of cell types, including hemopoietic precursors, and is coexpressed with Nramp1 in primary macrophages and macrophage cell lines. Nramp2 is expressed as a 90-100-kD integral membrane protein extensively modified by glycosylation (>40% of molecular mass). Subcellular localization studies by immunofluorescence and confocal microscopy indicate distinct and nonoverlapping localization for Nramp1 and Nramp2. Nramp1 is expressed in the lysosomal compartment, whereas Nramp2 is not detectable in the lysosomes but is expressed primarily in recycling endosomes and also, to a lower extent, at the plasma membrane, colocalizing with transferrin. These findings suggest that Nramp2 plays a key role in the metabolism of transferrin-bound iron by transporting free Fe2+ across the endosomal membrane and into the cytoplasm.

Animals↗
PubMed1999

Liver-specific and seasonal expression of transgenic Atlantic salmon harboring the winter flounder antifreeze protein gene.

We have analyzed the inheritance and expression of a line of transgenic salmon harboring the antifreeze protein gene from the winter flounder. The genomic clone 2A-7 coding for a major liver-type antifreeze protein gene (wflAFP-6) was integrated into the salmon genome. From a transgenic founder (#1469), an F3 generation was produced. In this study, southern blot analysis showed that only one copy of the antifreeze protein transgene was integrated into a unique site in F3 transgenic fish. The integration site was cloned and characterized. Northern analysis indicated that the antifreeze protein mRNA was only expressed in the liver and showed seasonal variation. All of the F3 offspring contained similar levels of the antifreeze protein precursor protein in the sera and the sera of these offspring showed a characteristic hexagonal ice crystal pattern indicating the presence of antifreeze activity. In addition, the antifreeze protein precursor protein level was found to vary with the season, being highest in the month of November and lowest in May. This study had demonstrated a tissue-specific and stable expression of the antifreeze protein transgene in the F3 generation of the transgenic salmon 1469 line.

Animals↗
PubMed1999

Enzyme activity and protein of multiple forms of choline acetyltransferase: effects of calyculin A and okadaic acid.

Choline acetyltransferase (ChAT) appears to exist in multiple forms, three of which can be isolated biochemically as cytosolic (cChAT), ionically-membrane bound (ibChAT) and non-ionic membranous (mChAT). In this study, we first examined whether the quantitative distribution of enzyme protein and enzyme activity was the same. Enzyme activity and ChAT protein distributed similarly: the majority of ChAT activity and protein were found in cChAT followed by mChAT and least activity and amount were in ibChAT. Our second objective was to investigate the effects of calyculin A or okadaic acid on the subcellular distribution of ChAT activity and amount from rat hippocampal formation. Calyculin A and okadaic acid decreased significantly (p < 0.01) cytosolic and membranous ChAT activity; ionically-bound ChAT was not significantly (p > 0.67) different from control. Removal of calyculin A or okadaic acid restored cytosolic ChAT activity (p > 0.9 as compared to control), but not membranous enzyme activity (p < 0.05 as compared to control). The immunoreactive cytosolic ChAT was reduced significantly (p < 0.01) by calyculin A and okadaic acid. Enzyme amount of membranous ChAT was decreased significantly by calyculin A (p < 0.01) and okadaic acid (p < 0.001). Enzyme amount of ionically-bound ChAT was not changed (p > 0.99) by either of these two phosphatase inhibitors. This investigation demonstrates that alterations in ChAT activity of each subfraction parallel changes in enzyme amounts in the same fractions.

Animals↗