Determination of differential activities of soluble and membrane-bound catechol-O-methyltransferase in tissues and erythrocytes

Ellingson, Todd; Duddempudi, Sushil; Greenberg, Benjamin D.; Hooper, Douglas; Eisenhofer, Graeme

doi:10.1016/s0378-4347(99)00125-5

Cited by 36 publications

(37 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results demonstrate that COMT activities in rat liver and kidney were much higher than those in rat erythrocyte (22.7 AE 1.14 and 4.62 AE 0.55 pmol/min/mg protein, for S-and MB-COMT, respectively). This result is comparable to those of other reports (Nohta et al, 1986;Ellingson et al, 1999). Further, S-COMT activity is 10-20 times higher than MB-COMT activity in both liver and kidney.…”

Section: Resultssupporting

confidence: 91%

Rat liver and kidney catechol‐O‐methyltransferase activity measured by high‐performance liquid chromatography with fluorescence detection

Tsunoda

Takezawa

Masuda

et al. 2002

Biomedical Chromatography

View full text Add to dashboard Cite

We have previously reported a highly sensitive method for the measurement of catechol-O-methyltransferase (COMT) activities in rat erythrocytes with norepinephrine (NE), an endogenous native substrate, using high-performance liquid chromatography (HPLC)-fluorescence or peroxyoxalate chemiluminescence reaction detection. Applying this method to COMT activities in rat liver and kidney, known to have the highest activities of all organs, the optimum reaction conditions were investigated. Under the optimum conditions, soluble (S)-COMT and membrane-bound (MB)-COMT activities in rat liver, with NE as a substrate, were 2.17 AE 0.33 and 0.16 AE 0.02 nmol/min/mg protein (n = 5), respectively. In rat kidney, S-COMT and MB-COMT activities were 1.81 AE 0.20 and 0.079 AE 0.009 nmol/min/mg protein (n = 5), respectively. Since liver and kidney play important roles in inactivating catecholamines, using the proposed method would yield critical information to delineate the role of metabolism of catecholamines in rat tissues.

show abstract

Section: Resultssupporting

confidence: 91%

Rat liver and kidney catechol‐O‐methyltransferase activity measured by high‐performance liquid chromatography with fluorescence detection

Tsunoda

Takezawa

Masuda

et al. 2002

Biomedical Chromatography

View full text Add to dashboard Cite

show abstract

“…5). Importantly, the COMT in chromaffin cells is mainly present as the membrane-bound form of the enzyme (Eisenhofer et al, 1998a;Ellingson et al, 1999). This isoform has a much higher affinity for catecholamines than does the soluble form found in most other tissues, such as in the liver and kidneys (Roth, 1992).…”

Section: Neuronal and Extraneuronal Catecholamine Metabolismmentioning

confidence: 99%

Catecholamine Metabolism: A Contemporary View with Implications for Physiology and Medicine

2004

Self Cite

View full text Add to dashboard Cite

“…Prior to performing the COMT assay, an aliquot of the soluble and pellet fractions were used to estimate protein concentration and for western blot analysis to confirm proper separation of the MB-and S-COMT isoforms. The COMT assay used here is a modified version of those described previously (Reenila et al, 1995;Reenila et al, 1997;Ellingson et al, 1999;Pihlavisto and Reenila, 2002). Reaction samples contained 180μl of tissue (from either the S-or the MB-COMT-enriched fractions) in a total reaction volume of 500μl.…”

Section: Mb-comt and S-comt Activity Assaysmentioning

confidence: 99%

Alterations in striatal dopamine catabolism precede loss of substantia nigra neurons in a mouse model of juvenile neuronal ceroid lipofuscinosis

et al. 2007

View full text Add to dashboard Cite

Batten disease, or juvenile neuronal ceroid lipofuscinosis (JNCL), results from mutations in the CLN3 gene. This disorder presents clinically around the age of five years with visual deficits progressing to include seizures, cognitive impairment, motor deterioration, hallucinations, and premature death by the third to forth decade of life. The motor deficits include coordination and gait abnormalities, myoclonic jerks, inability to initiate movements, and spasticity. Previous work from our laboratory has identified an early reduction in catechol-O-methyltransferase (COMT), an enzyme responsible for the efficient degradation of dopamine. Alterations in the kinetics of dopamine metabolism could cause the accumulation of undegraded or unsequestered dopamine leading to the formation of toxic dopamine intermediates. We report an imbalance in the catabolism of dopamine in three month Cln3 -/-mice persisting through nine months of age that may be causal to oxidative damage within the striatum at nine months of age. Combined with the Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. HHS Public Access Author Manuscript Author ManuscriptAuthor ManuscriptAuthor Manuscript previously reported inflammatory changes and loss of post-synaptic D1α receptors, this could facilitate cell loss in striatal projection regions and underlie a general locomotion deficit that becomes apparent at twelve months of age in Cln3 -/-mice. This study provides evidence for early changes in the kinetics of COMT in the Cln3 -/-mouse striatum, affecting the turnover of dopamine, likely leading to neuron loss and motor deficits. These data provide novel insights into the basis of motor deficits in JNCL and how alterations in dopamine catabolism may result in oxidative damage and localized neuronal loss in this disorder.

show abstract

Determination of differential activities of soluble and membrane-bound catechol-O-methyltransferase in tissues and erythrocytes

Cited by 36 publications

References 30 publications

Rat liver and kidney catechol‐O‐methyltransferase activity measured by high‐performance liquid chromatography with fluorescence detection

Rat liver and kidney catechol‐O‐methyltransferase activity measured by high‐performance liquid chromatography with fluorescence detection

Catecholamine Metabolism: A Contemporary View with Implications for Physiology and Medicine

Alterations in striatal dopamine catabolism precede loss of substantia nigra neurons in a mouse model of juvenile neuronal ceroid lipofuscinosis

Contact Info

Product

Resources

About