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1.
Aliment Pharmacol Ther ; 44(4): 400-10, 2016 08.
Article in English | MEDLINE | ID: mdl-27291852

ABSTRACT

BACKGROUND: Real-world data are needed to inform hepatitis C virus (HCV) treatment decisions. AIM: To assess the comparative effectiveness of ledipasvir/sofosbuvir ± ribavirin (LDV/SOF ± RBV) vs. ombitasvir/paritaprevir/ritonavir + dasabuvir (OPrD) ± RBV in genotype 1 HCV patients treated in routine medical practice. METHODS: Observational intent-to-treat cohort of genotype 1 patients initiating 8 or 12 weeks of LDV/SOF ± RBV or 12 weeks of OPrD ± RBV. Sustained virological response (SVR) required RNA below the limit of quantification at least 10 weeks after end of treatment. RESULTS: 6961 patients initiated LDV/SOF (N = 4478), LDV/SOF + RBV (N = 1269), OPrD (N = 297), and OPrD + RBV (N = 917) at 126 facilities. Intention-to-treat SVR rates were 91.4% (3813/4170) for LDV/SOF, 90.0% (1098/1220) for LDV/SOF + RBV, 95.1% (269/283) for OPrD and 85.8% (746/869) for OPrD + RBV. SVR rates in those completing 8 weeks of LDV/SOF were 91.7% (1223/1333) and 12 weeks of LDV/SOF 94.6% (2475/2615), LDV/SOF + RBV 92.2% (1033/1120), OPrD 98.0% (248/253) and OPrD + RBV 95.5% (705/738). Significant predictors of SVR were African American race (OR 0.71, 95%CI 0.59-0.86, P < 0.001), body mass index (BMI) > 30 kg/m(2) (OR 0.73, 95% CI 0.60-0.89, P = 0.002), FIB4 > 3.25 (OR 0.60, 95% CI 0.49-0.72, P < 0.001), OPrD + RBV compared to LDV/SOF (OR 0.60, 95% CI 0.48-0.76, P < 0.001) and subtype 1b (OR 1.38, 95% CI 1.11-1.71, P = 0.003). For those completing 12 weeks, FIB-4 > 3.25 and high BMI remained significant predictors. CONCLUSIONS: In this robust real-world cohort, SVR rates were similar to clinical trials. FIB-4 > 3.25 and high BMI were significant negative predictors of SVR. Reduced odds of SVR in African Americans and with OPrD + RBV likely arose from excess early discontinuation as these factors were no longer significant, when limited to patients completing a 12-week course.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis C, Chronic/drug therapy , 2-Naphthylamine , Adult , Black or African American , Aged , Aged, 80 and over , Anilides/therapeutic use , Benzimidazoles/therapeutic use , Carbamates/therapeutic use , Cyclopropanes , Drug Combinations , Drug Therapy, Combination , Female , Fluorenes/therapeutic use , Genotype , Hepacivirus/genetics , Hepatitis C, Chronic/blood , Humans , Lactams, Macrocyclic , Macrocyclic Compounds/therapeutic use , Male , Middle Aged , Proline/analogs & derivatives , RNA, Viral/blood , Ribavirin/therapeutic use , Ritonavir/therapeutic use , Sofosbuvir/therapeutic use , Sulfonamides/therapeutic use , Sustained Virologic Response , Uracil/analogs & derivatives , Uracil/therapeutic use , Valine , Young Adult
2.
Aliment Pharmacol Ther ; 42(5): 559-73, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26113432

ABSTRACT

BACKGROUND: Real-world effectiveness data are needed to inform hepatitis C virus (HCV) treatment decisions. AIM: To assess sustained virological response (SVR) of sofosbuvir (SOF)-based regimens in routine medical practice. METHODS: Observational, intent-to-treat cohort analysis of genotype 1 and 2 HCV-infected veterans initiating SOF-based regimens with recommended treatment duration of 12 weeks. RESULTS: Four thousand and twenty-six veterans with genotype 1 (N = 3203) and genotype 2 (N = 823) comprise the cohort. SVR rates for genotype 1 were 66.8% for SOF + peginterferon + ribavirin (RBV), 75.3% for SOF + simeprevir (SIM), 74.1% for SOF + SIM + RBV and for genotype 2 were 79.0% for SOF + RBV. Genotype 1 patients were less likely to achieve SVR with BMI ≥30 (OR 0.64, 95% CI 0.49-0.84, P < 0.001), a history of decompensated liver disease (OR 0.51, 95% CI 0.36-0.71, P < 0.001), treatment experience (OR 0.58, 95% CI 0.48-0.71, P < 0.001), APRI >2 (OR 0.44, 95% CI 0.36-0.55, P < 0.001) and with SOF + PEG + RBV compared with SOF + SIM (OR 0.50, 95% CI 0.40-0.62, P < 0.001). Age, sex, race/ethnicity, diabetes and genotype subtype did not predict SVR. Odds of achieving SVR with SOF + SIM + RBV did not differ compared with SOF + SIM (OR 1.03, 95% CI 0.75-1.44, P = 0.86). Genotype 2 patients were less likely to achieve SVR with prior treatment experience (OR 0.55, 95% CI 0.35-0.88, P = 0.009) and APRI >2 (OR 0.39, 95% CI 0.25-0.62, P < 0.001). CONCLUSIONS: In this real-world cohort, SVR rates were lower than in clinical trials. Genotype 1 and 2 HCV-infected patients with advanced liver disease by APRI >2 or FIB-4 > 3.25 were significantly less likely to achieve SVR. For genotype 1, a SOF + SIM ± RBV regimen was associated with a higher likelihood of SVR.


Subject(s)
Antiviral Agents/therapeutic use , Hepacivirus/genetics , Hepatitis C/drug therapy , Sofosbuvir/therapeutic use , Veterans , Adult , Aged , Aged, 80 and over , Antiviral Agents/administration & dosage , Drug Therapy, Combination , Female , Genotype , Humans , Interferons/administration & dosage , Liver Cirrhosis/drug therapy , Male , Middle Aged , Ribavirin/administration & dosage , Simeprevir/administration & dosage , Sofosbuvir/administration & dosage
3.
Aliment Pharmacol Ther ; 39(1): 93-103, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24206566

ABSTRACT

BACKGROUND: Limited data exist on the effectiveness of boceprevir and telaprevir in routine practice. AIM: To assess the comparative effectiveness of boceprevir and telaprevir regimens. METHODS: In this observational, intent-to-treat cohort analysis of hepatitis C genotype 1-infected veterans initiated on peginterferon/ribavirin and boceprevir (n = 661) or telaprevir (n = 198), we determined sustained virological response (SVR), treatment discontinuation rates and adverse haematological events. Inverse probability-of-treatment weighting (IPTW) was used to estimate the effect of one drug over the other, with matched pairs and unweighted logistic regression on the entire cohort for comparison. RESULTS: Of 835 veterans, SVR occurred in 50% and 52% receiving boceprevir- and telaprevir-based treatment, respectively (P = 0.72). No significant differences occurred among subgroups: cirrhotics (37% vs. 39%, P = 0.94), null responders (23% vs. 18%, P = 0.81), partial responders (39% vs. 58%, P = 0.15) and relapsers (60% vs. 77%, P = 0.11). Early discontinuation rates for boceprevir and telaprevir, respectively, were 31% and 28% by week 24 (P = 0.46) and 54% and 45% by 48 weeks (in those completing at least 28 weeks) (P = 0.14). Choice of telaprevir over boceprevir was significantly associated with SVR in multivariate models (IPTW OR: 1.57, 95% CI: 1.10-2.25, P = 0.01; matched-pairs OR: 1.91, 95% CI: 1.23-3.00, P = 0.004; unweighted OR: 1.50 95% CI: 1.05-2.14, P = 0.02). Rates of haematological adverse events in boceprevir- and telaprevir-treated patients were as follows: anaemia 59% vs. 51%, P = 0.30, thrombocytopenia 41% vs. 48%, P = 0.26, neutropenia 41% vs. 27%, P = 0.04. CONCLUSIONS: Sustained virological response was more likely with telaprevir-based regimens compared with boceprevir-based regimens in routine medical practice, after accounting for patient differences. Early discontinuation and haematological events, however, were similar.


Subject(s)
Antiviral Agents/therapeutic use , Hepatitis C/drug therapy , Oligopeptides/therapeutic use , Proline/analogs & derivatives , Protease Inhibitors/therapeutic use , Antiviral Agents/adverse effects , Cohort Studies , Comparative Effectiveness Research , Female , Hepatitis C/epidemiology , Humans , Interferon-alpha/adverse effects , Interferon-alpha/therapeutic use , Male , Middle Aged , Neutropenia/chemically induced , Oligopeptides/adverse effects , Polyethylene Glycols/adverse effects , Polyethylene Glycols/therapeutic use , Proline/adverse effects , Proline/therapeutic use , Protease Inhibitors/adverse effects , Ribavirin/adverse effects , Ribavirin/therapeutic use , Thrombocytopenia/chemically induced , United States/epidemiology , Veterans
4.
Aliment Pharmacol Ther ; 35(1): 105-15, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22060887

ABSTRACT

BACKGROUND: Early predictors of response to hepatitis C virus (HCV) therapy, such as rapid virological response, are valuable for the identification of patients with a higher likelihood of treatment success. AIM: To identify predictors of rapid virological response in a real world setting. METHODS: Using the VA Clinical Case Registry, we identified patients with HCV mono-infection, without liver transplantation, who initiated peginterferon (PEG-IFN) and ribavirin (RBV) in 2007 or 2008 and had HCV RNA testing for RVR. Significant baseline characteristics from genotype specific univariate analyses were used in backwards stepwise models to identify significant independent predictors of RVR. RESULTS: The final cohort consisted of 2424 patients with genotype 1 (G1), 666 patients with genotype 2 (G2), and 419 patients with genotype 3 (G3). Rapid virological response rates were 15% for G1, 71% for G2 and 57% for G3. Sustained virological response rates were significantly higher in patients with rapid virological response than without, increasing from 18% to 52% in G1, 39% to 71% in G2, and 40% to 60% in G3 (P < 0.0001). A baseline HCV RNA < 500,000 IU/mL positively predicted RVR across all genotypes studied. In addition, for G1, Black race, Hispanic ethnicity, aspartate aminotransferase/alanine aminotransferase (AST/ALT) ≥ 0.6, ferritin ≥ 350 ng/mL, LDL< 100 mg/dL and diabetes; for G2, BMI ≥ 30 kg/m(2), platelets < 150 K/µL, LDL< 100 mg/dL and the use of PEG-IFN alfa-2b; and for G3, AST/ALT ≥ 1.0, all negatively predicted rapid virological response. CONCLUSION: We found several novel independent predictors of rapid virological response, including BMI, AST/ALT ratio, ferritin, platelets, LDL, diabetes and type of PEG-IFN prescribed, which may be useful in guiding treatment decisions in routine medical practice.


Subject(s)
Antiviral Agents/therapeutic use , Hepacivirus/drug effects , Hepatitis C, Chronic/drug therapy , Interferon-alpha/therapeutic use , Polyethylene Glycols/therapeutic use , Ribavirin/therapeutic use , Cohort Studies , Drug Therapy, Combination , Female , Genotype , Hepacivirus/genetics , Hepacivirus/isolation & purification , Hepatitis C, Chronic/virology , Humans , Interferon alpha-2 , Male , Middle Aged , Predictive Value of Tests , RNA, Viral/blood , Recombinant Proteins/therapeutic use , Time Factors , Treatment Outcome , United States , Veterans , Viral Load
5.
HIV Med ; 11(3): 209-15, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19863620

ABSTRACT

OBJECTIVE: The aim of the study was to describe Veterans Healthcare Administration (VHA) system-wide uptake of three HIV protease inhibitors: atazanavir, darunavir and tipranavir. METHODS: This retrospective cohort study evaluated VHA uptake of three target antiretrovirals and lopinavir/ritonavir in each complete 90-day quarter since approval to December 2007 using VHA HIV Clinical Case Registry data. We assessed uptake using number of new prescriptions, number of providers and facilities prescribing target agents, provider type, clinic type, facility size and location within four US regions. RESULTS: Overall, 6551 HIV-infected veterans received target antiretrovirals. Uptake was generally greatest within the first year after Food and Drug Administration (FDA) approval, and then slightly declined and plateaued. Geographically, early adoption of new antiretroviral drugs tended to occur in the Western USA, as evidenced by comparison of uptake patterns of new antiretrovirals to use of all antiretroviral agents. A small percentage of prescribers of all antiretrovirals were responsible for new prescriptions for target medications, particularly for darunavir and tipranavir. Providers at almost 50% of VHA facilities were prescribing these agents within the first year. CONCLUSIONS: Uptake of new antiretrovirals in the VHA generally reflected overall prescribing of all antiretrovirals, suggesting a lack of VHA impediments to new antiretrovirals in the healthcare system. Some regional variation in uptake among the targeted antiretrovirals occurred over time but tended to resolve after the first several months. Providers responsible for early prescribing of the target medications were limited to a fraction of providers who tended to be physicians who practised in infectious disease (ID) clinics at medium-sized facilities.


Subject(s)
Anti-Retroviral Agents/therapeutic use , HIV Infections/drug therapy , Oligopeptides/therapeutic use , Practice Patterns, Physicians'/trends , Pyridines/therapeutic use , Pyrones/therapeutic use , Sulfonamides/therapeutic use , Ambulatory Care Facilities/statistics & numerical data , Atazanavir Sulfate , Cohort Studies , Darunavir , Drug Approval , Drug Prescriptions/statistics & numerical data , Electronic Health Records , Female , Health Facility Size , Humans , Male , Practice Patterns, Physicians'/statistics & numerical data , Retrospective Studies , Time Factors , United States , United States Food and Drug Administration , Veterans
6.
Transbound Emerg Dis ; 55(7): 308-14, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18631229

ABSTRACT

Wild animals can play an important role in the epidemiology of infectious disease with significant public health, economic and ecological consequences. As it is often challenging to conduct unbiased surveillance in free-ranging mammal populations, passive, opportunistic case identification has been widely used for detection of disease events in wild animals. This study evaluated the role of different agencies and organizations in the Rocky Mountain Region of the USA to identify significant wildlife health events or aggregate information from multiple sources. Overall wildlife rehabilitators were in contact with the greatest number of animals; however, the data from these groups, in its current state, are insufficient for surveillance purposes. Wild animal data from all survey groups aggregated at the level of state wildlife organizations; these agencies are therefore central in this type of surveillance activity and require sufficient resources to ensure that appropriate testing is conducted.


Subject(s)
Animals, Wild , Communicable Diseases, Emerging/veterinary , Sentinel Surveillance/veterinary , Animals , Communicable Diseases, Emerging/epidemiology , Communicable Diseases, Emerging/transmission , Female , Male , Species Specificity , United States/epidemiology
7.
J Viral Hepat ; 13(12): 799-810, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17109679

ABSTRACT

The US Department of Veterans Affairs (VA) cares for many human immunodeficiency virus/hepatitis C virus (HIV/HCV)-coinfected patients. VA treatment recommendations indicate that all HIV/HCV-coinfected patients undergo evaluation for HCV treatment and list pretreatment assessment tests. We compared clinical practice with these recommendations. We identified 377 HIV/HCV-coinfected veterans who began HCV therapy with pegylated interferon and ribavirin and 4135 HIV/HCV-coinfected veterans who did not but were in VA care at the same facilities during the same period. We compared laboratory and clinical characteristics of the two groups and estimated multivariate logistic regression models of receipt of HCV treatment. Overall, patients had high rates of receipt of tests necessary for HCV pretreatment assessment. Patients starting HCV treatment had higher alanine aminotransferase (ALT), lower creatinine, higher CD4 counts and lower HIV viral loads than patients not starting HCV treatment. In the multivariate model, positive predictors of starting HCV treatment included being non-Hispanic whites, having higher ALTs, lower creatinines, higher HCV viral loads, higher CD4 counts, undetectable HIV viral loads and receiving HIV antiretrovirals. A history of chronic mental illness and a history of hard drug use were negative predictors. Most HIV/HCV-coinfected patients received the necessary HCV pretreatment assessments, although rates of screening for hepatitis A and B immunity can be improved. Having well-controlled HIV disease is by far the most important modifiable factor affecting the receipt of HCV treatment. More research is needed to determine if the observed racial differences in starting HCV treatment reflect biological differences, provider behaviour or patient preference.


Subject(s)
HIV Infections/drug therapy , HIV Infections/virology , HIV , Hepacivirus , Hepatitis C/drug therapy , Hepatitis C/virology , Veterans , Cohort Studies , Female , HIV Infections/diagnosis , Hepatitis C/diagnosis , Humans , Interferon alpha-2 , Interferon-alpha/therapeutic use , Male , Middle Aged , Polyethylene Glycols/therapeutic use , Recombinant Proteins , Ribavirin/therapeutic use , United States , United States Department of Veterans Affairs
8.
J Clin Epidemiol ; 54 Suppl 1: S12-5, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11750204

ABSTRACT

The Veterans Health Administration (VA) is the nation's largest public integrated health care system and the largest single provider of health care to HIV-positive patients in the United States. First established in 1992, the Immunology Case Registry (ICR) is a national-level administrative database originally designed to monitor health care service utilization. With its interface to the VA electronic medical record, the ICR provides an opportunity to monitor and improve the quality of clinical care for HIV-positive patients receiving VA care. To realize this potential, key data element enhancements and quality review systems are being put into place. A brief description of the population included in the ICR is provided, along with current data limitations and planned improvements for data collection. The ICR, now managed by a national quality management center, is being updated and systematically improved for local clinical use. As local data capture improves, the ICR will prove to be an invaluable resource for assessing the quality of HIV care in the VA system and patient outcomes from that care.


Subject(s)
HIV Infections/epidemiology , HIV Infections/therapy , Registries/standards , Veterans , Adult , Aged , CD4 Lymphocyte Count , Demography , Female , HIV Infections/immunology , Humans , Male , Middle Aged , Population Surveillance , Risk Factors , United States/epidemiology
9.
J Health Care Poor Underserved ; 12(4): 446-60, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11688195

ABSTRACT

California is rapidly implementing mandatory managed care for most of its Medicaid (Medi-Cal) beneficiaries. To assess the impact of this delivery system change, the authors analyzed a 1996 statewide population-based random-sample telephone survey of 3,563 adults between the ages of 18 and 64. Respondents with Medi-Cal managed care and Medi-Cal fee-for-service rated access to care and quality of care significantly higher than uninsured respondents yet lower than low-income privately insured individuals. While the authors did not find a difference in health care access and quality among Medi-Cal managed care enrollees compared with Medi-Cal fee-for-service enrollees, they also did not find that managed care provided any observed advantages to Medi-Cal recipients.


Subject(s)
Attitude to Health , Managed Care Programs/standards , Medicaid/organization & administration , Poverty , State Health Plans , Adolescent , Adult , California , Health Services Accessibility , Humans , Middle Aged , Preventive Health Services/statistics & numerical data , Quality of Health Care , United States
10.
J Gen Intern Med ; 16(12): 815-21, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11903760

ABSTRACT

OBJECTIVE: To compare specialist and primary care physician participation in California's Medicaid fee-for-service and managed care programs. DESIGN: Cross-sectional survey. PARTICIPANTS: A probability sample stratified by county and by race of 962 specialist physicians and 713 primary care physicians practicing in the 13 largest counties in California in 1998. MEASUREMENTS AND ANALYSIS: We used physician self-report from mailed questionnaires to compare acceptance of new Medicaid and new Medicaid managed care patients by specialists versus primary care physicians and by physician demographics, practice setting, attitudes toward Medicaid patients, and attitudes toward Medicaid managed care. We analyzed results using logistic regression with data weighted to represent the total population of primary care and specialist physicians in the 13 counties. MAIN RESULTS: Specialists were as likely as primary care physicians to have any Medicaid patients in their practices (56% vs 56%; P=.9). Among physicians accepting any new patients, specialists were more likely than primary care physicians to be taking new Medicaid patients but were significantly more likely to limit their acceptance to only Medicaid fee-for-service patients. Thus, specialists were much less likely than primary care physicians to accept new Medicaid managed care patients. After controlling for physician demographics, practice settings, and attitudes toward Medicaid patients and Medicaid managed care, specialists remained much less likely to accept new Medicaid managed care patients. CONCLUSIONS: Expansion of Medicaid managed care may decrease access to specialists as specialists were less likely to accept new Medicaid managed care patients compared to Medicaid fee-for-service patients. Any decrease in access may be mitigated if states are able to contract with group model HMOs and to recruit minority physicians.


Subject(s)
Attitude of Health Personnel , Managed Care Programs , Medicaid , Medicine , Physicians, Family , Specialization , Adult , Aged , California , Cross-Sectional Studies , Female , Humans , Male , Middle Aged
11.
Br J Pharmacol ; 100(4): 793-9, 1990 Aug.
Article in English | MEDLINE | ID: mdl-2145051

ABSTRACT

1. The possibility of 5-HT2 receptor modulation of central 5-HT1A receptor function has been examined using the 5-hydroxytryptamine (5-HT) behavioural syndrome induced by 5-HT1A receptor active drugs in rats. 2. The 5-HT2/5-HTIC antagonist ritanserin (0.1-2 mg kg-1) increased the 5-HT behavioural syndrome induced by submaximally effective doses of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT), 5-methoxy-N,N-dimethyltryptamine (5-MeODMT) and gepirone. 3. Pretreatment with the 5-HT2/5-HT1C antagonist ICI 170,809 (0.25-5 mg kg-1) also enhanced the behavioural syndrome induced by 8-OH-DPAT or 5-MeODMT. 4. The 5-HT2/alpha 1-adrenoceptor antagonist ketanserin in a low dose (0.25 mg kg-1) significantly increased the 5-HT behavioural syndrome induced by 8-OH-DPAT or 5-MeODMT, while in a higher dose (2.5 mg kg-1) this drug decreased the response. Experiments with prazosin indicate that the higher dose of ketanserin might reduce the 5-HT behavioural syndrome through blockade of alpha 1-adrenoceptors. 5. Ritanserin and ICI 170,809 had no effect on apomorphine-induced stereotypy or hyperactivity, indicating that these drugs do not produce non-specific behavioural activation. 6. Ritanserin and ICI 170,809 inhibited quipazine-induced wet dog shakes at doses similar to those enhancing the 5-HT behavioural syndrome. 7. We suggest that ritanserin, ICI 170,809 and ketanserin enhance 5-HT1A agonist-induced behaviour through blockade of an inhibitory 5-HT2 receptor regulating or coupled to 5-HT1A receptor-mediated function.


Subject(s)
Behavior, Animal/drug effects , Central Nervous System/drug effects , Receptors, Serotonin/drug effects , 8-Hydroxy-2-(di-n-propylamino)tetralin , Animals , Apomorphine/pharmacology , Dose-Response Relationship, Drug , Haloperidol/pharmacology , Ketanserin/pharmacology , Male , Methoxydimethyltryptamines/pharmacology , Piperidines/pharmacology , Prazosin/pharmacology , Pyrimidines/pharmacology , Quinolines/pharmacology , Rats , Rats, Inbred Strains , Ritanserin , Serotonin/pharmacology , Stereotyped Behavior/drug effects , Tetrahydronaphthalenes/pharmacology
12.
Eur J Pharmacol ; 176(3): 331-40, 1990 Feb 13.
Article in English | MEDLINE | ID: mdl-1970304

ABSTRACT

The present study examined the actions of the putative 5-HT1A antagonist BMY 7378 on central pre- and postsynaptic 5-HT1A function in the rat in vivo. Unlike the direct acting 5-HT1A agonist 8-hydroxy-2-(di-n-pro-pylamino)tetralin (8-OH-DPAT), BMY 7378 (0.25-5 mg/kg s.c.) did not induce the full postsynaptically mediated 5-HT behavioural syndrome (forepaw treading, head weaving, flat body posture hindlimb abduction). Indeed, the maximal 5-HT behavioural syndrome scores of BMY 7378 were about 10% of those for 8-OH-DPAT. Following pretreatment, however, BMY 7378 dose dependently (0.25-5 mg/kg s.c.) reduced to undetectable levels forepaw treading and head weaving induced by 8-OH-DPAT (0.75 mg/kg s.c.). BMY 7378 also inhibited stereotypy and locomotor activity induced by 0.5 mg/kg apomorphine although this effect was only statistically significant at the highest dose tested (5 mg/kg). In contrast to its apparent 5-HT1A antagonist properties in the behavioural experiments, BMY 7378 caused a marked and dose-dependent (0.01-1.0 mg/kg s.c.) decrease of 5-HT release in ventral hippocampus of the anaesthetized rat as detected by brain microdialysis. This effect of BMY 7378 had a similar onset and duration of action but with slightly reduced efficacy compared to that previously described for 8-OH-DPAT. As with 8-OH-DPAT, the inhibitory effect of BMY 7378 on 5-HT release was attenuated by pretreatment with the 5-HT1 receptor/beta-adrenoceptor antagonist pindolol (8 mg/kg s.c.) but not its counterpart propranolol (20 mg/kg s.c.). Pretreatment with a combination of the beta 1- and beta 2-adrenoceptor antagonists metoprolol (4 mg/kg s.c.) and ICI 118 551 (4 mg/kg s.c.), respectively, did not alter the 5-HT response to BMY 7378. From these data we conclude that BMY 7378 is a mixed agonist/antagonist at central 5-HT1A receptors.


Subject(s)
Piperazines/pharmacology , Serotonin Antagonists/pharmacology , 8-Hydroxy-2-(di-n-propylamino)tetralin , Adrenergic beta-Antagonists/pharmacology , Animals , Apomorphine/pharmacology , Brain Chemistry/drug effects , Dialysis , Dose-Response Relationship, Drug , Drug Interactions , Hippocampus/drug effects , Hippocampus/metabolism , Male , Motor Activity/drug effects , Rats , Rats, Inbred Strains , Receptors, Serotonin/drug effects , Stereotyped Behavior/drug effects , Tetrahydronaphthalenes/pharmacology
14.
Pharmacol Biochem Behav ; 30(3): 657-63, 1988 Jul.
Article in English | MEDLINE | ID: mdl-3211975

ABSTRACT

Rats were given systemic injections of one of a series of novel GABA compounds which can penetrate the blood-brain barrier to release GABA into the brain. They were then tested on lateral hypothalamic self-stimulation behavior using a rate-frequency paradigm to discriminate effects on reward from those on motor/performance. Both reward and, to a lesser extent, motor/performance impairments were found with all GABA compounds. In more extensive testing with one compound, LG2, no differences in the effects of three salts (acetate, ascorbate, and tartarate) were found except that the tartarate salt effects decayed more rapidly.


Subject(s)
Hypothalamic Area, Lateral/physiology , Self Stimulation/drug effects , gamma-Aminobutyric Acid/analogs & derivatives , gamma-Aminobutyric Acid/pharmacology , Animals , Electric Stimulation , Hypothalamic Area, Lateral/drug effects , Male , Motor Activity/drug effects , Rats , Rats, Inbred Strains , Reinforcement, Psychology , Structure-Activity Relationship
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