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1.
J Atten Disord ; 26(5): 696-705, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34085581

RESUMEN

OBJECTIVE: The Before School Functioning Questionnaire and Parent Rating of Evening and Morning Behavior-Revised assess early morning (BSFQ, PREMB-R AM subscale) and late afternoon/evening (PREMB-R PM subscale) functional impairment in children with ADHD. Clinically meaningful improvements were identified and applied to a trial of delayed-release and extended-release methylphenidate (DR/ER-MPH) in children with ADHD (NCT02520388) to determine if the statistically-determined improvements in functional impairment were also clinically meaningful. METHOD: Clinically meaningful improvements in BSFQ/PREMB-R were established post hoc by receiver operating characteristics curves, using anchors of Clinical Global Impression-Improvement (CGI-I) = 1 and CGI-I ≤ 2. Percentages of participants achieving these thresholds were calculated. RESULTS: Thresholds for CGI-I = 1/CGI-I ≤ 2, respectively, were 27/20 (BSFQ), 5/3 (PREMB-R AM), and 9/5 (PREMB-R PM)-point decreases. More children achieved clinically meaningful improvements with DR/ER-MPH versus placebo (all p < .05). CONCLUSION: DR/ER-MPH increased proportions of children achieving clinically meaningful improvements in BSFQ and PREMB-R.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad , Estimulantes del Sistema Nervioso Central , Metilfenidato , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Estimulantes del Sistema Nervioso Central/uso terapéutico , Niño , Preparaciones de Acción Retardada , Método Doble Ciego , Humanos , Metilfenidato/uso terapéutico , Resultado del Tratamiento
2.
J Clin Psychiatry ; 82(4)2021 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-34166587

RESUMEN

Objective: Delayed-release and extended-release methylphenidate (DR/ER-MPH), the first stimulant predicted to be absorbed primarily in the colon, demonstrated significant improvements in attention-deficit/hyperactivity disorder (ADHD) symptoms and functional impairment from awakening until evening versus placebo in clinical trials. The clinical significance of these improvements was explored post hoc by examining response and remission thresholds as well as safety in the context of dose optimization.Methods: Data from the open-label, treatment-optimization phase of a phase 3 study of DR/ER-MPH in children (aged 6-12 years) with ADHD, as diagnosed by DSM-5 criteria and enrolled between July 2015 and March 2016, were analyzed. Thresholds for response (anchored to Clinical Global Impressions-Improvement scale [CGI-I] score of 1 or 2) and remission were applied to ADHD Rating Scale-IV (ADHD-RS-IV), Before School Functioning Questionnaire (BSFQ), and Parent Rating of Evening and Morning Behavior, Revised, Morning Subscale (PREMB-R AM) and Evening Subscale (PREMB-R PM) scores. Rates of response, remission, and treatment-emergent adverse events by starting dose were examined.Results: Mean DR/ER-MPH dose increased from 29.7 mg/d at baseline (51% on 20 mg/d; 49% on 40 mg/d) to 66.2 mg/d at week 6. At week 6, most participants achieved response/remission thresholds (response/remission: ADHD-RS-IV: 97%/89%; BSFQ: 98%/94%; PREMB-R AM: 94%/98%; PREMB-R PM: 91%/84%). More participants starting on a 40-mg versus 20-mg dose achieved thresholds at week 1 (P < .02). Weekly treatment-emergent adverse event rates over the open-label period were similar between starting doses.Conclusions: When DR/ER-MPH dosing was optimized for ADHD symptom control throughout the day, the majority of participants achieved thresholds indicating all-day control of ADHD symptoms and functional impairment to the level of their non-ADHD peers.Trial Registration: Data used in this post hoc analysis came from the study with ClinicalTrials.gov identifier: NCT02493777.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Estimulantes del Sistema Nervioso Central/administración & dosificación , Metilfenidato/administración & dosificación , Estimulantes del Sistema Nervioso Central/efectos adversos , Niño , Preparaciones de Acción Retardada/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Metilfenidato/efectos adversos , Inducción de Remisión , Resultado del Tratamiento
3.
J Child Adolesc Psychopharmacol ; 31(3): 179-186, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33797983

RESUMEN

Objectives: Inadequately controlled symptoms and associated impaired functioning have a significant negative impact on caregivers of children with attention-deficit/hyperactivity disorder (ADHD). This study aimed to assess the impact of evening-dosed, delayed-release and extended-release methylphenidate (DR/ER-MPH) treatment on caregiver strain, measured by the Caregiver Strain Questionnaire (CGSQ), and present post hoc psychometric analyses assessing the reliability and validity of the CGSQ, its ability to detect change (responsiveness), and to derive responder definitions. Methods: The CGSQ was an exploratory efficacy endpoint in a phase 3, 3-week, randomized, double-blind, multicenter, placebo-controlled, forced-dose titration trial of DR/ER-MPH in children aged 6-12 years with ADHD (NCT02520388). Psychometric properties of the CGSQ evaluated post hoc included internal consistency using Cronbach's alpha; test/retest reliability using intraclass correlation coefficients (ICCs); construct validity (known groups and convergent/divergent validity); responsiveness to changes in assessments of ADHD severity (ADHD Rating Scale-IV [ADHD-RS-IV], Conners' Global Index-Parent [CGI-P], and Clinical Global Impression-Severity [CGI-S]/CGI-Improvement [CGI-I]); and meaningful change threshold (MCT) using receiver operating characteristic curves, which were used to compare response between DR/ER-MPH and placebo groups. Results: Randomized DR/ER-MPH (54.5) and placebo (54.9) groups had similar mean CGSQ scores at screening. Caregivers of children on DR/ER-MPH reported significant reductions in CGSQ scores after 3 weeks of DR/ER-MPH treatment versus placebo (least-squares mean: 41.2 vs. 49.1; p < 0.001). The CGSQ demonstrated strong internal consistency (Cronbach's alpha = 0.93) and good test/retest reliability (ICC = 0.72). Known groups, convergent/divergent validity, and responsiveness were demonstrated from relationships between the CGSQ and the CGI-S, ADHD-RS-IV, and CGI-P. The mean anchor-based MCT for CGSQ total score was estimated as -9.0 (DR/ER-MPH vs. placebo: 53.2% vs. 29.9% p = 0.003). Conclusions: CGSQ scores significantly decreased after 3 weeks of DR/ER-MPH treatment versus placebo, and the CGSQ was found to be a valid and reliable measure of strain in caregivers of children with ADHD. Clinical trial registration identification number: NCT02520388.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Cuidadores/psicología , Estimulantes del Sistema Nervioso Central/uso terapéutico , Preparaciones de Acción Retardada/administración & dosificación , Metilfenidato/uso terapéutico , Psicometría/estadística & datos numéricos , Encuestas y Cuestionarios/estadística & datos numéricos , Niño , Método Doble Ciego , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Resultado del Tratamiento
4.
Clin Ther ; 42(12): 2332-2340, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33168234

RESUMEN

PURPOSE: HLD200 is the first evening-dosed, delayed-release and extended-release methylphenidate (DR/ER-MPH) designed to delay initial release of MPH and provide treatment effects throughout the day and into the evening for individuals with attention-deficit/hyperactivity disorder (ADHD). Because DR/ER-MPH is uniquely absorbed in the colon, it cannot be substituted for other ADHD medications on a milligram-per-milligram basis. To provide clinicians with a target dose range for DR/ER-MPH when transitioning patients from a prior ADHD medication, dose conversion ratios (DCRs) between prior medication doses and optimized doses of DR/ER-MPH were determined post hoc from a pivotal Phase III study of children (aged 6-12 years) with ADHD. METHODS: DR/ER-MPH doses were optimized over a 6-week open-label period. DCRs were calculated between optimized doses of DR/ER-MPH at week 6 and prior stable doses of ADHD medication. FINDINGS: Mean DCRs ranged from 1.8 to 4.3 for optimized DR/ER-MPH dose versus previous stable dose for individuals taking an extended-release stimulant monotherapy. DCRs for those taking an immediate-release stimulant monotherapy ranged from 4.7 to 6.0. IMPLICATIONS: In a Phase III trial of children with ADHD, optimized doses of DR/ER-MPH were higher than doses of prior ADHD medications, but the adverse event profile was consistent with that of other MPHs. Higher DCRs compared with those predicted by bioavailability differences are consistent with a predicted dose-dependent duration of effect for DR/ER-MPH: with increasing doses, absorption is extended but with an attenuated increase in Cmax compared with MPH formulations absorbed in the upper bowel. These data may help guide clinicians to optimize DR/ER-MPH doses. ClinicalTrials.gov identifier: NCT02493777.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Estimulantes del Sistema Nervioso Central/administración & dosificación , Metilfenidato/administración & dosificación , Niño , Preparaciones de Acción Retardada/administración & dosificación , Método Doble Ciego , Femenino , Humanos , Masculino
5.
J Child Adolesc Psychopharmacol ; 30(1): 2-14, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31464511

RESUMEN

Objectives: HLD200, a once-daily, evening-dosed, delayed-release and extended-release methylphenidate (DR/ER-MPH), was designed to provide therapeutic effect beginning upon awakening and lasting into the evening. This pivotal, randomized, double-blind, multicenter, placebo-controlled, phase 3 trial assessed improvements in functional impairment across the day using multiple validated measures tailored for different settings and time of day in children (6-12 years) with attention-deficit/hyperactivity disorder (ADHD). Methods: Following a 6-week, open-label titration of DR/ER-MPH to an optimal dose (20, 40, 60, 80, or 100 mg/day) and dosing time (8:00 PM ±1.5 hours), participants were randomized to treatment-optimized DR/ER-MPH or placebo for 1 week. The primary endpoint was the model-adjusted average of postdose Swanson, Kotkin, Agler, M-Flynn, and Pelham Scale combined scores (SKAMP CS) over a 12-hour laboratory classroom day (8:00 AM to 8:00 PM). The key secondary endpoint was the Parent Rating of Evening and Morning Behavior-Revised, Morning (PREMB-R AM) subscale. Secondary/exploratory measures included the PREMB-R Evening (PREMB-R PM) subscale and Permanent Product Measure of Performance (Attempted [PERMP-A] and Correct [PERMP-C]). Safety endpoints included treatment-emergent adverse events (TEAEs). Results: After the treatment-optimization phase, the mean optimized dose was 66.2 mg and the most common prescribed dosing time was 8:00 PM. Double-blind DR/ER-MPH treatment significantly improved functional impairment versus placebo in the early morning (PREMB-R AM: p < 0.001), averaged over the classroom day (SKAMP CS: p < 0.001), and in the late afternoon/evening (PREMB-R PM: p = 0.003) in the intent-to-treat population (N = 117). Average PERMP-A (p = 0.006) and PERMP-C (p = 0.009) also indicated improved classroom performance with DR/ER-MPH versus placebo. In the double-blind phase, TEAEs did not differ between DR/ER-MPH and placebo groups and no serious TEAEs or TEAEs leading to discontinuation were reported. Conclusion: DR/ER-MPH was well tolerated and demonstrated significant improvements versus placebo in functional impairment throughout the day across different settings in children with ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Estimulantes del Sistema Nervioso Central/efectos adversos , Estimulantes del Sistema Nervioso Central/uso terapéutico , Niño , Preparaciones de Acción Retardada/efectos adversos , Preparaciones de Acción Retardada/uso terapéutico , Método Doble Ciego , Femenino , Humanos , Masculino , Escalas de Valoración Psiquiátrica/estadística & datos numéricos
6.
J Child Adolesc Psychopharmacol ; 29(3): 181-191, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30810347

RESUMEN

OBJECTIVES: HLD200, an oral, once-daily, evening-dosed, delayed-release, and extended-release methylphenidate (DR/ER-MPH), was designed to provide efficacy from the early morning, throughout the day, and into the evening to individuals with attention-deficit/hyperactivity disorder. The objectives were to evaluate DR/ER-MPH pharmacokinetic (PK) properties in healthy adults, including dose proportionality, food effect, the potential of accumulation using multiple-dose modeling, and bioavailability compared to an immediate-release MPH (IR MPH). METHODS: Three open-label, single-dose, crossover studies were conducted, all with a 7-day washout between treatments. In Study I, 20 subjects received evening-dosed DR/ER-MPH (20 and 100 mg) followed by a medium-fat breakfast; 13 subjects received a subsequent 100-mg dose of DR/ER-MPH followed by a low-fat breakfast. In Study II, 18 subjects were evaluated after receiving evening-dosed DR/ER-MPH (100 mg) under 3 conditions: immediately after a high-fat meal, sprinkled on applesauce, and in a fasted state. In Study III, 11 and 12 subjects received evening-dosed DR/ER-MPH (100 mg) and morning-dosed IR MPH (20 mg), respectively. RESULTS: DR/ER-MPH demonstrated dose proportionality between 20- and 100-mg doses. DR/ER-MPH PK parameters were not significantly affected by breakfast content or by sprinkling capsule contents. A high-fat meal immediately preceding evening dosing did not affect total MPH exposure but lowered peak MPH exposure by 14% and 11% versus fasted and sprinkled states, and time to peak exposure was delayed by ∼2.5 hours; these PK differences are unlikely to be clinically significant. Based on multiple-dose simulations using data from Study I, negligible accumulation of DR/ER-MPH was predicted. The relative bioavailability for DR/ER-MPH compared to IR MPH was 73.9%. No serious adverse events (AEs) were reported, and the observed AEs were consistent with MPH. There were no discontinuations in Studies I and III, but three participants withdrew in Study II due to AEs. CONCLUSIONS: Evening-dosed DR/ER-MPH demonstrated dose proportionality and can be administered with or without food. Significant accumulation is unlikely with multiple dosing.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Estimulantes del Sistema Nervioso Central/administración & dosificación , Preparaciones de Acción Retardada/administración & dosificación , Metilfenidato , Adulto , Disponibilidad Biológica , Estudios Cruzados , Dieta , Femenino , Voluntarios Sanos , Humanos , Masculino , Metilfenidato/administración & dosificación , Metilfenidato/farmacocinética , Persona de Mediana Edad , Adulto Joven
7.
J Clin Psychiatry ; 81(1)2019 12 10.
Artículo en Inglés | MEDLINE | ID: mdl-31846241

RESUMEN

OBJECTIVE: Children with attention-deficit/hyperactivity disorder (ADHD) frequently manifest behavioral difficulties in the morning prior to school and in the afternoons and evenings. We sought to establish norms for 2 time-specific measures of functioning: the Before School Functioning Questionnaire (BSFQ) and the Parent Rating of Evening and Morning Behavior Scale, Revised (PREMB-R), which includes Morning (AM) and Evening (PM) subscales. METHODS: The normative online survey of a representative US sample of 1,200 primary caregivers of children and adolescents aged between 6 and 17 years was conducted in June 2016. A quota system was used whereby caregivers of 50 male and 50 female children or adolescents were recruited in each age group, ie, 100 parents for each of the 12 age groups. Diagnosis of ADHD relied on a caregiver's report that his or her child was so diagnosed by a health professional. RESULTS: Across all items of the BSFQ, youth with current untreated ADHD or a history of ADHD were rated as more severely ill than those without ADHD (all unadjusted P values < .001), even after adjustment for psychiatric comorbidity (all adjusted P values < .001). A similar pattern was observed for the PREMB-R AM (all unadjusted P values < .001; all adjusted P values < .001, except for item 1 [P = .01]) and PREMB-R PM (all unadjusted P values < .001; all adjusted P values < .001). The use of a large population sample allowed for computation of age-stratified norms for 4 thresholds of risk: screening risk (80th percentile), mild functional impairment (90th percentile), moderate functional impairment (93rd percentile), and severe functional impairment (98th percentile). CONCLUSIONS: The norms generated by this study can guide clinicians in the use of the BSFQ and PREMB-R for identifying those ADHD youth who may be experiencing difficulties in the early morning and late afternoon/evening. Such tools are needed given the availability of treatments that can target ADHD symptoms and impairments at these extremes of the daily routine.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/psicología , Conducta Infantil/psicología , Actividades Cotidianas/psicología , Adolescente , Niño , Femenino , Humanos , Masculino , Padres , Valores de Referencia , Encuestas y Cuestionarios , Factores de Tiempo
8.
J Child Adolesc Psychopharmacol ; 28(1): 10-18, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29039979

RESUMEN

OBJECTIVE: Current extended-release (ER) formulations of psychostimulants used for treatment of attention-deficit/hyperactivity disorder (ADHD) provide an extended duration of ADHD symptom control; however, the onset of efficacy can be protracted and variable, leaving the early morning untreated. The primary objective was to characterize the single-dose pharmacokinetics and tolerability of HLD200, an evening-dosed, delayed-release (DR) and ER formulation of methylphenidate (MPH), in healthy adults and in adolescents and children with ADHD. METHODS: The pharmacokinetics and tolerability of a single, oral evening dose of HLD200 (54 mg) were evaluated in two single-center open-label studies: the first in healthy adults (n = 12) and the second in adolescents (n = 18) and children (n = 11) with ADHD. Primary pharmacokinetic endpoints were the rate and extent of MPH absorption (Cmax and area under the curve [AUC]) and time to peak concentration (Tmax). These parameters were calculated using noncompartmental analysis. RESULTS: HLD200 produced a pharmacokinetic profile characterized by an 8- to 10-hour delay in MPH release, followed by a period of extended controlled release, resulting in an ascending absorption profile that coincided with the early morning and afternoon. Mean values (coefficient of variation [CV]%) of weight-adjusted pharmacokinetic parameters were similar in adults and in adolescents and children with ADHD: Cmax ([ng/mL]/[mg/kg]) was 9.1 (35.2), 8.8 (34.5), and 7.4 (30.1); AUC0-t ([ng · h/mL]/[mg/kg]) was 126.5 (35.5), 129.4 (34.8), and 129.7 (27.3); and Tmax (hours) was 15.6 (11.1), 17.1 (14.5), and 17.7 (14.1), respectively. Intersubject variability in the mean time to achieve ascending plasma MPH concentrations of 2, 3, 4, and 5 ng/mL was low (CV: 7.8%-17.7%). CONCLUSIONS: Evening-dosed HLD200 produces the intended DR and ER pharmacokinetic profile that provides a consistent predictable delay in initial MPH release until the early morning, followed by extended release across the day. The body weight-adjusted pharmacokinetics of HLD200 were similar between adults and adolescents and children with ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Estimulantes del Sistema Nervioso Central/administración & dosificación , Metilfenidato/administración & dosificación , Administración Oral , Adolescente , Adulto , Factores de Edad , Área Bajo la Curva , Estudios de Casos y Controles , Estimulantes del Sistema Nervioso Central/farmacocinética , Niño , Estudios Cruzados , Preparaciones de Acción Retardada , Femenino , Humanos , Masculino , Metilfenidato/farmacocinética , Persona de Mediana Edad , Factores de Tiempo , Adulto Joven
9.
J Atten Disord ; 22(11): 1066-1073, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-26700792

RESUMEN

OBJECTIVE: Children with ADHD frequently manifest behavioral difficulties in the morning prior to school. We sought to assess the reliability and validity of the Daily Parent Rating of Evening and Morning Behavior Scale, Revised (DPREMB-R) morning score as a measure of morning behaviors impaired by ADHD. METHOD: We used data from a clinical trial of HLD200 treatment in pediatric participants with ADHD to address our objectives. RESULTS: The DPREMB-R morning score showed significant internal homogeneity, test-retest reliability ( r = .52-.45), and good concurrent validity ( r = .50-.71). CONCLUSION: The DPREMB-R morning score could be a useful instrument for assessing treatment efficacy in the morning before school.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/psicología , Trastornos de la Conducta Infantil/diagnóstico , Adolescente , Inhibidores de Captación Adrenérgica/uso terapéutico , Clorhidrato de Atomoxetina/uso terapéutico , Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Escala de Evaluación de la Conducta/normas , Niño , Trastornos de la Conducta Infantil/psicología , Preescolar , Método Doble Ciego , Femenino , Humanos , Masculino , Padres , Reproducibilidad de los Resultados , Instituciones Académicas , Factores de Tiempo
10.
J Child Adolesc Psychopharmacol ; 27(6): 474-482, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29172680

RESUMEN

OBJECTIVE: Evening-dosed HLD200 is a delayed-release and extended-release methylphenidate (DR/ER-MPH) formulation consisting of uniform, dual-layered microbeads with an inner drug-loaded core. DR/ER-MPH is designed to delay the initial release of drug by 8-10 hours, and thereafter, provide a controlled, extended drug release to target onset of effect upon awakening that lasts into the evening. This phase 3 study evaluated the safety and efficacy of DR/ER-MPH on symptoms and temporal at-home functional impairment in children with attention-deficit/hyperactivity disorder (ADHD). METHODS: This 3-week, randomized, double-blind, multicenter, placebo-controlled, parallel-group, forced-dose titration trial evaluated DR/ER-MPH (40-80 mg/day) in children aged 6-12 years with ADHD. Primary efficacy endpoint was the ADHD rating scale-IV (ADHD-RS-IV), and the key secondary endpoints were the Before-School Functioning Questionnaire (BSFQ), and Parent Rating of Evening and Morning Behavior-Revised, morning (PREMB-R AM) and evening (PREMB-R PM). Safety measures included spontaneously reported treatment-emergent adverse events (TEAEs) and two TEAEs of special interest, appetite suppression and insomnia (with direct questioning on sleep disturbance). RESULTS: One hundred sixty-one participants were included in the intent-to-treat population (DR/ER-MPH, n = 81; placebo, n = 80). After 3 weeks, DR/ER-MPH achieved significant improvements versus placebo in ADHD symptoms (least-squares [LS] mean ADHD-RS-IV: 24.1 vs. 31.2; p = 0.002), and at-home early morning (LS mean BSFQ: 18.7 vs. 28.4; p < 0.001; LS mean PREMB-R AM: 2.1 vs. 3.6; p < 0.001) and late afternoon/evening (LS mean PREMB-R PM: 9.4 vs. 12.2; p = 0.002) functional impairment. Commonly reported TEAEs (≥10%) were insomnia and decreased appetite. CONCLUSIONS: DR/ER-MPH was generally well tolerated and demonstrated significant improvements versus placebo in ADHD symptoms and at-home functional impairments in the early morning, late afternoon, and evening in children with ADHD.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/tratamiento farmacológico , Metilfenidato/efectos adversos , Metilfenidato/uso terapéutico , Apetito/efectos de los fármacos , Estimulantes del Sistema Nervioso Central/uso terapéutico , Niño , Preparaciones de Acción Retardada/uso terapéutico , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Esquema de Medicación , Femenino , Humanos , Masculino , Trastornos del Inicio y del Mantenimiento del Sueño/inducido químicamente , Resultado del Tratamiento
11.
Psychopharmacology (Berl) ; 164(2): 193-9, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12404082

RESUMEN

RATIONALE: The potentiation of the acoustic startle response (ASR) by stimuli associated with aversive events is mediated via the amygdala and is used as an index of "anxiety" and "fear". In laboratory animals, cholecystokinin(B) (CCK(B)) agonists increase anxiety and fear and activation of amygdala CCK(B) receptors potentiates ASR. Additionally, antagonism of CCK(B) receptors attenuates fear-potentiated ASR. OBJECTIVES: To investigate the putative role of CCK(B) receptors in individual differences in fear and anxiety, we examined individual differences in amygdala CCK(B) receptor binding for animals demonstrating low versus high baseline and fear-potentiated ASR. Additionally, we examined individual differences in CCK(B) binding for animals demonstrating low versus high anxiety-like behavior on the elevated plus-maze (EPM). METHODS: Male Wistar rats were tested in the ASR, fear-potentiated ASR, and EPM paradigms. Following testing, brain slices were mounted and incubated with 50 pM (125)I-CCK8 (non-sulfated), a selective CCK(B) receptor ligand, in the presence or absence of 1 micro M non-radioactively labeled CCK and then exposed on tritium-sensitive film for 2-3 days. RESULTS: Animals with high fear-potentiated ASR showed decreased CCK(B) receptor binding in both the basolateral and central amygdaloid nuclei. Animals with high anxiety-like responses on the EPM showed decreased CCK(B) binding in the basolateral, but not central, amygdala. There were no differences in amygdala CCK(B) binding in animals demonstrating low versus high baseline ASR. None of the groups showed differences in CCK(B) receptor binding in the nucleus accumbens. CONCLUSIONS: These results show that there is a down-regulation of amygdala CCK(B) receptor binding in animals demonstrating greater anxiety-like responding in the fear-potentiated ASR and EPM models of anxiety, possibly as a compensation for increased CCK activity.


Asunto(s)
Amígdala del Cerebelo/metabolismo , Ansiedad/metabolismo , Receptores de Colecistoquinina/metabolismo , Estimulación Acústica , Amígdala del Cerebelo/fisiología , Análisis de Varianza , Animales , Ansiedad/fisiopatología , Autorradiografía/métodos , Conducta Animal , Colecistoquinina/metabolismo , Condicionamiento Clásico , Miedo/fisiología , Masculino , Aprendizaje por Laberinto/fisiología , Núcleo Accumbens/diagnóstico por imagen , Núcleo Accumbens/metabolismo , Núcleo Accumbens/fisiología , Cintigrafía , Ratas , Ratas Wistar , Receptores de Colecistoquinina/fisiología , Reflejo de Sobresalto/fisiología
12.
Brain Res ; 1001(1-2): 95-107, 2004 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-14972658

RESUMEN

DA release in the nucleus accumbens (NAcc) is a critical substrate mediating locomotor behavior. Cholecystokinin (CCK) is co-localized with dopamine (DA) in up to 90% of mesolimbic DA neurons. We have previously shown that while CCKA receptor antagonists generally do not affect locomotor behaviors, systemic administration of a CCKA receptor antagonist attenuates amphetamine (AMPH)-induced locomotion in animals previously treated chronically with AMPH, suggesting that chronic stimulant pretreatment may sensitize CCK systems. The present studies examined this issue by testing the effects of CCKA antagonists on AMPH- and novel environment-induced locomotor activity following two manipulations which are known to alter mesolimbic system function: Chronic AMPH administration and chronic restraint stress (RS). Additionally, CCK immunoreactivity in the mesolimbic system following these manipulations was examined using immunohistochemistry. Results indicated that intra-NAcc microinjections of the selective CCKA receptor antagonist PD-140548 attenuated AMPH-induced and novel environment-induced locomotion only in animals which had previously been exposed to chronic AMPH or chronic RS pretreatment. However, chronic AMPH and chronic RS did not produce detectable changes in the number of CCK-immunostained neurons in the ventral tegmental area (VTA) or substantia nigra (SN), or in CCK levels in any of the subregions of the NAcc. Together, these results suggest that the role of endogenous CCK in the modulation of locomotor behaviors is sensitized following chronic psychostimulant or chronic RS exposure. However, this sensitization does not appear to be accompanied by changes in the overall basal levels of CCK or in the number of CCK-positive cells within the mesoaccumbens system.


Asunto(s)
Anfetamina/farmacología , Estimulantes del Sistema Nervioso Central/farmacología , Colecistoquinina/fisiología , Actividad Motora/efectos de los fármacos , Estrés Fisiológico/fisiopatología , Animales , Conducta Animal/efectos de los fármacos , Esquema de Medicación , Inmunohistoquímica/métodos , Indoles/farmacología , Masculino , Núcleo Accumbens/efectos de los fármacos , Núcleo Accumbens/metabolismo , Ratas , Receptor de Colecistoquinina A/antagonistas & inhibidores , Restricción Física/métodos
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