| 1. |
- Wang, Peng, et al.
(författare)
-
Depression-like behavior in rat: Involvement of galanin receptor subtype 1 in the ventral periaqueductal gray
- 2016
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : NATL ACAD SCIENCES. - 0027-8424 .- 1091-6490. ; 113:32, s. E4726-E4735
-
Tidskriftsartikel (refereegranskat)abstract
- The neuropeptide galanin coexists in rat brain with serotonin in the dorsal raphe nucleus and with noradrenaline in the locus coeruleus (LC), and it has been suggested to be involved in depression. We studied rats exposed to chronic mild stress (CMS), a rodent model of depression. As expected, these rats showed several endophenotypes relevant to depression-like behavior compared with controls. All these endophenotypes were normalized after administration of a selective serotonin reuptake inhibitor. The transcripts for galanin and two of its receptors, galanin receptor 1 (GALR1) and GALR2, were analyzed with quantitative real-time PCR using laser capture microdissection in the following brain regions: the hippocampal formation, LC, and ventral periaqueductal gray (vPAG). Only Galr1 mRNA levels were significantly increased, and only in the latter region. After knocking down Galr1 in the vPAG with an siRNA technique, all parameters of the depressive behavioral phenotype were similar to controls. Thus, the depression-like behavior in rats exposed to CMS is likely related to an elevated expression of Galr1 in the vPAG, suggesting that a GALR1 antagonist could have antidepressant effects.
|
|
| 2. |
- Ji, Shuangmin, et al.
(författare)
-
Population pharmacokinetic-pharmacodynamic (PopPK/PD) modeling of risperidone and its active metabolite in Chinese schizophrenia patients
- 2016
-
Ingår i: International journal of clinical pharmacology and therapeutics. - 0946-1965. ; 54:5, s. 378-389
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: Risperidone is a second-generation antipsychotic agent commonly used in the treatment of 31.1% of schizophrenia patients in China, it is the most commonly-prescribed antipsychotic agent. Despite the abundant use of risperidone, population pharmacokinetic-pharmacodynamic models of risperidone have not been performed in Chinese schizophrenia patients. The objective of this study was to develop a population pharmacokinetic-pharmacodynamic (PopPK/PD) model to describe the PK behavior and efficacy of risperidone and 9-hydroxy-risperidone (active metabolite) in Chinese patients. Methods: Plasma concentration data (702 measurements from 131 patients) and positive and negative syndrome scale (PANSS) scores (258 observations from 56 patients) were analyzed using a nonlinear mixed-effects modeling (NONMEM) approach with first-order conditional estimation with interaction (FOCEI). The influence of potential covariates was evaluated. Model robustness was assessed using external validation, nounalized prediction distribution error, nonparametric bootstrap, and visual predictive check approaches. Results: Risperidone concentration data were well described by a one-compartmental model incorporating an additional compartment that refers to the concentration profiles of 9-hydroxy-risperidone. A complex absorption procedure was incorporated into the model to describe the metabolism of risperidone to 9-hydroxy-risperidone in the gastrointestinal (GI) tract. A binomial distribution in the estimated clearance (CL) of risperidone has been identified in our model. Decrease in PANSS score along with total AUC (AUC(total)) of risperidone and 9-hydroxy-risperidone was best characterized by an E-max model with 3 transit compartments describing the delay of drug effect. Conclusions: Considerable differences in PK behavior and drug effect of risperidone have been identified among Chinese extensive metabolizing (EM) and poor metabolizing (PM) patients. This PopPK/PD model may fulfill individualized treatment in clinical practice and may potentially be transferred to other antipsychotic therapies.
|
|
