Chemicals and Drugs Commons^™

Antibiotic Prophylaxis Is Associated With Subsequent Resistant Infections In Children With An Initial Extended-Spectrum-Cephalosporin-Resistant Enterobacteriaceae Infection., Sibani Das, Amanda L. Adler, Arianna Miles-Jay, Matthew P. Kronman, Xuan Qin, Scott J. Weissman, C A. Burnham, Alexis Elward, Jason G. Newland, Rangaraj Selvarangan, Kaede V. Sullivan, Theoklis Zaoutis, Danielle M. Zerr

Manuscripts, Articles, Book Chapters and Other Papers

The objective of this study was to assess the association between previous antibiotic use, particularly long-term prophylaxis, and the occurrence of subsequent resistant infections in children with index infections due to extended-spectrum-cephalosporin-resistant Enterobacteriaceae We also investigated the concordance of the index and subsequent isolates. Extended-spectrum-cephalosporin-resistant Escherichia coli and Klebsiella spp. isolated from normally sterile sites of patients aged species, resistance determinants, and fumC-fimH (E. coli) or tonB (Klebsiella pneumoniae) type were identical to those of the index isolate. In total, 323 patients had 396 resistant isolates; 45 (14%) patients had ≥1 subsequent resistant infection, totaling 73 …

In Vivo Characterization Of Cyp2d6*12, *29 And *84 Using Dextromethorphan As A Probe Drug: A Case Report., Andrea Gaedigk, Greyson P. Twist, Emily G. Farrow, Jennifer Lowry, Sarah E. Soden, Neil A. Miller

Manuscripts, Articles, Book Chapters and Other Papers

CYP2D6*84 was first described in a Black South African subject, however, its function remains unknown. Astrolabe, a probabilistic scoring tool developed in our laboratory to call genotypes from whole genome sequence, identified CYP2D6*84 in a trio. The father presented with intermediate metabolism when challenged with the CYP2D6 probe drug dextromethorphan (DM/dextrorphan [DX] = 0.0839). Since his second allele, CYP2D6*12, is nonfunctional, the observed activity is derived by CYP2D6*84. This finding suggests that the allele's hallmark P267H causes decreased activity toward DM and that this allele should receive a value of 0.5 for Activity Score calculations. The mother's DM/DX of 0.0543 …

Polymer Micelle Formulation For The Proteasome Inhibitor Drug Carfilzomib: Anticancer Efficacy And Pharmacokinetic Studies In Mice, Ji Eun Park, Se-Eun Chun, Derek Alexander Reichel, Jee Sun Min, Su-Chan Lee, Songhee Han, Gongmi Ryoo, Yunseok Oh, Shin-Hyung Park, Heon-Min Ryu, Kyung Bo Kim, Ho-Young Lee, Soo Kyung Bae, Younsoo Bae, Wooin Lee

Pharmaceutical Sciences Faculty Publications

Carfilzomib (CFZ) is a peptide epoxyketone proteasome inhibitor approved for the treatment of multiple myeloma (MM). Despite the remarkable efficacy of CFZ against MM, the clinical trials in patients with solid cancers yielded rather disappointing results with minimal clinical benefits. Rapid degradation of CFZ in vivo and its poor penetration to tumor sites are considered to be major factors limiting its efficacy against solid cancers. We previously reported that polymer micelles (PMs) composed of biodegradable block copolymers poly(ethylene glycol) (PEG) and poly(caprolactone) (PCL) can improve the metabolic stability of CFZ in vitro. Here, we prepared the CFZ-loaded PM, PEG-PCL-deoxycholic …

Oral Cannabidiol Does Not Produce A Signal For Abuse Liability In Frequent Marijuana Smokers, Shanna Babalonis, Margaret Haney, Robert J. Malcolm, Michelle R. Lofwall, Victoria R. Votaw, Steven Sparenborg, Sharon L. Walsh

Behavioral Science Faculty Publications

Background—Cannabidiol (CBD) is a naturally occurring constituent of the marijuana plant. In the past few years, there has been great interest in the therapeutic effects of isolated CBD and it is currently being explored for numerous disease conditions (e.g., pain, epilepsy, cancer, various drug dependencies). However, CBD remains a Schedule I drug on the U.S. Controlled Substances Act (CSA). Despite its status, there are no well-controlled data available regarding its abuse liability.

Methods—Healthy, frequent marijuana users (n=31) were enrolled in this within subject, randomized, placebo-controlled, double-blind, multisite study that administered oral cannabidiol (0, 200, 400, 800 …

Outpatient Parenteral Antimicrobial Therapy In Pediatric Medicaid Enrollees., Jennifer Goldman, Troy Richardson, Jason G. Newland, Brian R. Lee, Jeffrey S. Gerber, Matt Hall, Matthew Kronman, Adam L. Hersh

Manuscripts, Articles, Book Chapters and Other Papers

Background: Outpatient parenteral antimicrobial therapy (OPAT) is overused in cases where highly bioavailable oral alternatives would be equally effective. However, the scope of OPAT use for children nationwide is poorly understood. Our objective was to characterize OPAT use and clinical outcomes for a large population of pediatric Medicaid enrollees treated with OPAT.

Methods: We analyzed the Truven MarketScan Medicaid claims database between 2009 and 2012. An OPAT episode was identified by capturing children with claims data indicating home infusion therapy for an intravenous antimicrobial. We characterized OPAT use by describing patient demographics, diagnoses, and antimicrobials prescribed. We categorized an antimicrobial …

The Effect Of Sazetidine-A And Other Nicotinic Ligands On Nicotine Controlled Goal-Tracking In Female And Male Rats, S. Charntikov, A. M. Falco, K. Fink, Linda P. Dwoskin, R. A. Bevins

Pharmaceutical Sciences Faculty Publications

Nicotine is the primary addictive component of tobacco products and its complex stimulus effects are readily discriminated by humans and non-human animals. Previous preclinical research investigating directly the nature of the nicotine stimulus has been limited to male rodents. The current study began to address this significant gap in the literature by training female and male rats to discriminate 0.4 mg/kg nicotine from saline in the discriminated goal-tracking task. In this task, access to sucrose was intermittently available on nicotine session. On saline session, intermixed with nicotine sessions on separate days, sucrose was not available. Both sexes acquired the discrimination …

Metronidazole Metabolism In Neonates And The Interplay Between Ontogeny And Genetic Variation., Laura A. Wang, Daniel Gonzalez, J Steven Leeder, Rachel F. Tyndale, Robin E. Pearce, Daniel K. Benjamin, Gregory L. Kearns, Michael Cohen-Wolkowiez, Best Pharmaceuticals For Children Act-Pediatric Trials Network Steering Committee

Manuscripts, Articles, Book Chapters and Other Papers

No abstract provided.

Metronidazole Metabolism In Neonates And The Interplay Between Ontogeny And Genetic Variation., Laura A. Wang, Daniel Gonzalez, J Steven Leeder, Rachel F. Tyndale, Robin E. Pearce, Daniel K. Benjamin, Gregory L. Kearns, Michael Cohen-Wolkowiez, Best Pharmaceuticals For Children Act-Pediatric Trials Network Steering Committee

Manuscripts, Articles, Book Chapters and Other Papers

No abstract provided.

Taurine's Effect On Cocaine Reward And Neurogenesis In The Adolescent Male Rat Brain., Avery E. Villa-Gonzalez

Dissertations and Theses

Adolescence is a developmentally critical transition from childhood to adulthood including both maturation of the body and the brain. Neuroplastic changes result in dynamic organization of the brain during adolescence, leaving them vulnerable to development of mental illness and drug-seeking behavior. According to the United Nations Office on Drugs and Crime, the psychostimulant cocaine is the second most popular illicit drug in the world. Cocaine, amongst having many detrimental effects, has shown to also decrease hippocampal neurogenesis, resulting in decreased neuroplasticity and cognitive dysfunction. Previous students in our laboratory have shown that treatment of adult male rats with the essential …

Flavored Electronic Cigarette Use And Smoking Among Youth., Hongying Dai, Jianqiang Hao

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND AND OBJECTIVE: Flavored electronic cigarettes (e-cigarettes) are not prohibited in the United States, and e-cigarette flavors proliferate on the market. This study sought to examine flavored e-cigarette use and its association with smoking among youth.

METHODS: Estimates of flavored e-cigarette use from the 2014 National Youth Tobacco Survey were investigated. A logistic regression model was used to assess whether flavored e-cigarette use was associated with (1) intention to initiate cigarette use among never-smoking youth (n = 16 471), (2) intention to quit tobacco use among current-smoking youth (n = 1338), and (3) perception of tobacco's danger among all respondents …

Rationale And Design Of The Children's Oncology Group (Cog) Study Alte1621: A Randomized, Placebo-Controlled Trial To Determine If Low-Dose Carvedilol Can Prevent Anthracycline-Related Left Ventricular Remodeling In Childhood Cancer Survivors At High Risk For Developing Heart Failure., Saro H. Armenian, Melissa M. Hudson, Ming Hui Chen, Steven D. Colan, Lanie Lindenfeld, George Mills, Aida Siyahian, Sarah Gelehrter, Ha Dang, Wendy Hein, Daniel M M. Green, Leslie L. Robison, F Lennie Wong, Pamela S. Douglas, Smita Bhatia

Manuscripts, Articles, Book Chapters and Other Papers

Background: Anthracyclines are widely used in the treatment of childhood cancer. One of the well-recognized side-effects of anthracycline therapy is dose-dependent cardiomyopathy that may progress to heart failure (HF) years after completion of cancer-directed therapy. This study will evaluate the efficacy of low-dose beta-blocker (carvedilol) for HF risk reduction in childhood cancer survivors at highest risk for HF. The proposed intervention has the potential to significantly reduce chronic cardiac injury via interruption of neurohormonal systems responsible for left ventricular (LV) remodeling, resulting in improved cardiac function and decreased risk of HF. The intervention is informed by previous studies demonstrating efficacy …

Expanding The Phenotype Associated With Naa10-Related N-Terminal Acetylation Deficiency., Chloé Saunier, Svein Isungset Støve, Bernt Popp, Bénédicte Gérard, Marina Blenski, Nicholas Ahmew, +Several Additional Authors

Pediatrics Faculty Publications

N-terminal acetylation is a common protein modification in eukaryotes associated with numerous cellular processes. Inherited mutations in NAA10, encoding the catalytic subunit of the major N-terminal acetylation complex NatA have been associated with diverse, syndromic X-linked recessive disorders, whereas de novo missense mutations have been reported in one male and one female individual with severe intellectual disability but otherwise unspecific phenotypes. Thus, the full genetic and clinical spectrum of NAA10 deficiency is yet to be delineated. We identified three different novel and one known missense mutation in NAA10, de novo in 11 females, and due to maternal germ …

Pharmacokinetics And Bioequivalence Of A Liquid Formulation Of Hydroxyurea In Children With Sickle Cell Anemia., Jeremie H. Estepp, Chiara Melloni, Courtney D. Thornburg, Paweł Wiczling, Zora Rogers, Jennifer A. Rothman, Nancy S. Green, Robert Liem, Amanda M. Brandow, Shelley E. Crary, Thomas H. Howard, Maurine H. Morris, Andrew Lewandowski, Uttam Garg, William J. Jusko, Kathleen A. Neville, Best Pharmaceuticals For Children Act-Pediatric Trials Network Administrative Core Committee

Manuscripts, Articles, Book Chapters and Other Papers

Hydroxyurea (HU) is a crucial therapy for children with sickle cell anemia, but its off-label use is a barrier to widespread acceptance. We found HU exposure is not significantly altered by liquid vs capsule formulation, and weight-based dosing schemes provide consistent exposure. HU is recommended for all children starting as young as 9 months of age with sickle cell anemia (SCA; HbSS and HbSβspan(0) thalassemia); however; a paucity of pediatric data exists regarding the pharmacokinetics (PK) or the exposure-response relationship of HU. This trial aimed to characterize the PK of HU in children and to evaluate and compare the bioavailability …

Long-Term Velaglucerase Alfa Treatment In Children With Gaucher Disease Type 1 Naïve To Enzyme Replacement Therapy Or Previously Treated With Imiglucerase., Laurie Smith, William Rhead, Joel Charrow, Suma P. Shankar, Ashish Bavdekar, Nicola Longo, Rebecca Mardach, Paul Harmatz, Thomas Hangartner, Hak-Myung Lee, Eric Crombez, Gregory M. Pastores

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND: Gaucher Disease type 1 (GD1) often manifests in childhood. Early treatment with enzyme replacement therapy (ERT) may prevent disease complications. We report the assessment of velaglucerase alfa ERT in pediatric GD1 patients who participated in a long-term extension study (HGT-GCB-044, ClinicalTrials.gov Identifier NCT00635427).

METHODS: Safety and efficacy were evaluated in pediatric patients receiving velaglucerase alfa 30-60U/kg by intravenous infusion every other week. In addition to key hematological and visceral efficacy assessments, exploratory assessments conducted specifically in pediatric patients included evaluation of height, bone age, bone marrow burden, and Tanner stage of puberty.

RESULTS: The study included 24 pediatric patients. …

Sglt2 Inhibitor Therapy Improves Blood Glucose But Does Not Prevent Diabetic Bone Disease In Diabetic Dba/2j Male Mice, Kathryn M. Thrailkill, R. Clay Bunn, Jeffry S. Nyman, Mallikarjuna R. Rettiganti, Gael E. Cockrell, Elizabeth C. Wahl, Sasidhar Uppuganti, Charles K. Lumpkin, John L. Fowlkes

Barnstable Brown Diabetes Center Faculty Publications

Persons with type 1 and type 2 diabetes have increased fracture risk, attributed to deficits in the microarchitecture and strength of diabetic bone, thought to be mediated, in part, by the consequences of chronic hyperglycemia. Therefore, to examine the effects of a glucose-lowering SGLT2 inhibitor on blood glucose (BG) and bone homeostasis in a model of diabetic bone disease, male DBA/2J mice with or without streptozotocin (STZ)-induced hyperglycemia were fed chow containing the SGLT2 inhibitor, canagliflozin (CANA), or chow without drug, for 10 weeks of therapy. Thereafter, serum bone biomarkers were measured, fracture resistance of cortical bone was assessed by …

Efficacy Of Galactose And Adalimumab In Patients With Resistant Focal Segmental Glomerulosclerosis: Report Of The Font Clinical Trial Group., Howard Trachtman, Suzanne Vento, Emily Herreshoff, Milena Radeva, Jennifer Gassman, Daniel T. Stein, Virginia J. Savin, Mukut Sharma, Jochen Reiser, Changli Wei, Michael Somers, Tarak Srivastava, Debbie S. Gipson

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND: Patients with resistant focal segmental glomerulosclerosis (FSGS) who are unresponsive to corticosteroids and other immunosuppressive agents are at very high risk of progression to end stage kidney disease. In the absence of curative treatment, current therapy centers on renoprotective interventions that reduce proteinuria and fibrosis. The FONT (Novel Therapies for Resistant FSGS) Phase II clinical trial (NCT00814255, Registration date December 22, 2008) was designed to assess the efficacy of adalimumab and galactose compared to standard medical therapy which was comprised of lisinopril, losartan, and atorvastatin.

METHODS: Key eligibility criteria were biopsy confirmed primary FSGS or documentation of a causative …

Oseltamivir-Warfarin Interaction In Hypoplastic Left Heart Syndrome: Case Report And Review., Jonathan B. Wagner, Susan M. Abdel-Rahman

Manuscripts, Articles, Book Chapters and Other Papers

An 8-year-old boy with hypoplastic left heart syndrome with a previous history of thrombosis within the inferior vena cava receiving stable warfarin dosing for anticoagulation was diagnosed with influenza B. He was subsequently placed on oseltamivir therapy according to the Centers for Disease Control and Prevention clinical practice guidelines. During the hospitalization, his international normalized ratio steadily increased to supratherapeutic levels and returned to baseline after discontinuation of oseltamivir therapy. This case represents a drug-drug interaction that has not been previously reported in children or adolescents. An extensive review of the pharmacokinetic and pharmacodynamic literature did not uncover a definitive …

Pupillometry: A Non-Invasive Technique For Pain Assessment In Paediatric Patients., Mark A. Connelly, Jacob T. Brown, Gregory L. Kearns, Rawni A. Anderson, Shawn D. St Peter, Kathleen A. Neville

Manuscripts, Articles, Book Chapters and Other Papers

OBJECTIVE: Pupillometry has been used to assess pain intensity and response to analgesic medications in adults. The aim of this observational study was to explore proof of concept for the use of this technique in paediatric patients. Changes in pupil parameters before and after opioid exposure also were evaluated.

DESIGN AND SETTING: This was a single-centre, prospective study conducted at an academic paediatric medical centre.

PATIENTS: Children 9-17 years of age undergoing elective surgical correction of pectus excavatum were enrolled into a protocol approved by the human ethical committee (institutional review board).

INTERVENTIONS: Pupil size and reactivity were measured using …

Aspirin Use And Knowledge In The Community: A Population- And Health Facility Based Survey For Measuring Local Health System Performance., Gregory A Roth, Catherine W. Gillespie, Ali A Mokdad, Danny D Shen, David W Fleming, Andy Stergachis, Christopher J L Murray, Ali H Mokdad

Pediatrics Faculty Publications

BACKGROUND: Little is known about the relationship between cardiovascular risk, disease and actual use of aspirin in the community.

METHODS: The Measuring Disparities in Chronic Conditions (MDCC) study is a community and health facility-based survey designed to track disparities in the delivery of health interventions for common chronic diseases. MDCC includes a survey instrument designed to collect detailed information about aspirin use. In King County, WA between 2011 and 2012, we surveyed 4633 white, African American, or Hispanic adults (45% home address-based sample, 55% health facility sample). We examined self-reported counseling on, frequency of use and risks of aspirin for …

Cinacalcet As Adjunctive Therapy For Hereditary 1,25-Dihydroxyvitamin D-Resistant Rickets., Tarak Srivastava, Uri S. Alon

Manuscripts, Articles, Book Chapters and Other Papers

Secondary hyperparathyroidism from inadequate calcium absorption in the gut, is the underlying pathophysiology for rachitic changes in hereditary vitamin D-resistant rickets (HVDRR). We describe a novel use of Cinacalcet to treat a child with HVDRR in whom conventional modes of therapy had to be discontinued. Cinacalcet therapy with high-dose oral calcium effectively normalized the metabolic abnormalities and bone condition. The relative ease of administration of the calcimimetic as a once- or twice-daily oral preparation, compared with traditional intravenous calcium administration, should encourage its move to the frontline of treatment of the disorder.

Serum 25-Hydroxyvitamin D Level And Acute-Phase Reaction Following Initial Intravenous Bisphosphonate., Tarak Srivastava, Hongying Dai, Connie J. Haney, Uri S. Alon

Manuscripts, Articles, Book Chapters and Other Papers

No abstract provided.

Atorvastatin May Have No Effect On Acute Phase Reaction In Children After Intravenous Bisphosphonate Infusion., Tarak Srivastava, Connie J. Haney, Uri S. Alon

Manuscripts, Articles, Book Chapters and Other Papers

Intravenous bisphosphonate therapy is associated with acute phase reaction characterized by fever and musculoskeletal pain. Bisphosphonates have been shown in vitro to activate gammadeltaT-cells to proliferate and produce cytokines, suggesting a role in acute phase reaction, which can be effectively blocked by statins. We conducted a double-blind randomized crossover placebo controlled study in 12 children (12.1 +/- 4.2 yr; 10 girls and 2 boys) receiving intravenous bisphosphonates to evaluate whether statins can be used to prevent acute phase reaction associated with therapy. Children received two cycles given 3-4 mo apart of intravenous bisphosphonate given on 2 consecutive days in each …

Rationale And Design Of A Trial Of Angiotensin-Converting Enzyme Inhibition In Infants With Single Ventricle., Daphne T. Hsu, Seema Mital, Chitra Ravishankar, Renee Margossian, Jennifer S. Li, Lynn A. Sleeper, Richard V. Williams, Jami C. Levine, Brian W. Mccrindle, Andrew M. Atz, Darlene Servedio, Lynn Mahony, Pediatric Heart Network Investigators, Girish S. Shirali

Manuscripts, Articles, Book Chapters and Other Papers

BACKGROUND: Angiotensin converting enzyme (ACE) inhibitors are known to improve clinical outcome and ventricular function in adults with heart failure. Infants with single-ventricle physiology show abnormalities in ventricular function as well as poor growth. The ability of an ACE inhibitor to preserve ventricular function and improve growth in these infants is unknown.

METHODS: The Pediatric Heart Network designed a randomized, double-blind trial to compare outcomes in infants with single-ventricle physiology receiving enalapril or placebo. Neonates < or =45 days old were eligible. The primary outcome is weight-for-age Z-score at 14 months of age. Secondary outcomes include other measures of somatic growth, laboratory and functional measures of heart failure, developmental indices, measures of ventricular size and function, and the relationship of the renin-angiotensin-aldosterone system genotype to the response to enalapril. The incidence and spectrum of adverse events will also be compared between treatment groups.

RESULTS: A total of 1,245 neonates were screened and 533 (43%) were eligible. The consent rate was 43%; 230 subjects were enrolled. Parental reluctance to …

Single Daily Dosing Ceftriaxone And Metronidazole Vs Standard Triple Antibiotic Regimen For Perforated Appendicitis In Children: A Prospective Randomized Trial., Shawn D. St Peter, Kuojen Tsao, Troy L. Spilde, G W. Holcomb Iii, Susan W. Sharp, J Patrick Murphy, Charles L. Snyder, Ronald J. Sharp, Walter S. Andrews, Daniel J. Ostlie

Manuscripts, Articles, Book Chapters and Other Papers

INTRODUCTION: Appendicitis is the most common emergency condition in children. Historically, a 3-drug regimen consisting of ampicillin, gentamicin, and clindamycin (AGC) has been used postoperatively for perforated appendicitis. A retrospective review at our institution has found single day dosing of ceftriaxone and metronidazole (CM) to be a more simple and cost-effective antibiotic strategy. Therefore, we performed a prospective, randomized trial to compare efficacy and cost-effectiveness of these 2 regimens.

METHODS: After internal review board approval (IRB no. 04 12-149), children found to have perforated appendicitis at appendectomy were randomized to either once daily dosing of CM (2 total doses per …

Urotensin Ii Modulates Rapid Eye Movement Sleep Through Activation Of Brainstem Cholinergic Neurons, Salvador Huitron-Resendiz, Morten P. Kristensen, Stephen L. Grupke, Christopher Tyler, Olivier Civelli, Christopher S. Leonard, Luis De Lecea

NYMC Faculty Publications

Urotensin II (UII) is a cyclic neuropeptide with strong vasoconstrictive activity in the peripheral vasculature. UII receptor mRNA is also expressed in the CNS, in particular in cholinergic neurons located in the mesopontine tegmental area, including the pedunculopontine tegmental (PPT) and lateral dorsal tegmental nuclei. This distribution suggests that the UII system is involved in functions regulated by acetylcholine, such as the sleep-wake cycle. Here, we tested the hypothesis that UII influences cholinergic PPT neuron activity and alters rapid eye movement (REM) sleep patterns in rats. Local administration of UII into the PPT nucleus increases REM sleep without inducing changes …

Tacrolimus As A Liver Flush Solution To Ameliorate The Effects Of Ischemia/Reperfusion Injury Following Liver Transplantation., Shawn D. St Peter, David J. Post, Manuel I. Rodriguez-Davalos, David D. Douglas, Adyr A. Moss, David C. Mulligan

Manuscripts, Articles, Book Chapters and Other Papers

The goal of this report is to evaluate in a prospective randomized fashion the effect of flushing hepatic allografts with tacrolimus before transplantation. A prospective, double-blinded, randomized trial was performed. Twenty patients receiving orthotopic liver transplants from October 2000 to October 2001 were randomized into two groups. Group 1 (active) was administered tacrolimus, 20 ng/mL, plus Plasma-lyte A (Baxter Healthcare Corp, Deerfield, IL) liver flush solution; and group 2 (placebo) was administered only Plasma-lyte A. Ischemia/reperfusion injury was assessed in both groups after transplantation by means of serum laboratory values to assess hepatocellular damage, synthetic function, and ion transport capacity. …

Impaired Fast-Spiking, Suppressed Cortical Inhibition, And Increased Susceptibility To Seizures In Mice Lacking Kv3.2 K+ Channel Proteins, David Lau, Eleazar Vega-Saenz De Miera, Diego Contreras, Alan Chow, Richard Paylor, Christopher S. Leonard, Bernardo Rudy

NYMC Faculty Publications

Voltage-gated K(+) channels of the Kv3 subfamily have unusual electrophysiological properties, including activation at very depolarized voltages (positive to -10 mV) and very fast deactivation rates, suggesting special roles in neuronal excitability. In the brain, Kv3 channels are prominently expressed in select neuronal populations, which include fast-spiking (FS) GABAergic interneurons of the neocortex, hippocampus, and caudate, as well as other high-frequency firing neurons. Although evidence points to a key role in high-frequency firing, a definitive understanding of the function of these channels has been hampered by a lack of selective pharmacological tools. We therefore generated mouse lines in which one …