Effects of risperidone treatment on the expression of hypothalamic neuropeptide in appetite regulation in Wistar rats

Kursungoz, Canan
Yanık, Tülin
Although the use of atypical antipsychotic drugs has been successful in the treatment of schizophrenia, they can cause some complications in the long-term use, including weight gain. Patients using these drugs tend to disrupt treatment primarily due to side effects. The atypical antipsychotic mechanism of action regulates a number of highly disrupted neurotransmitter pathways in the brains of psychotic patients but may also cause impairment of neurohorrnonal pathways in different brain areas. In this study, we investigated the circulating levels of hypothalamic neurohormones, which are related to appetite regulation; neuropeptide Y (NPY); alpha melanocyte stimulating hormone (alpha-MSH); cocaine and amphetamine regulated transcript (CART); agouti-related peptide (AgRP); and leptin in male Wistar rats, which were treated with risperidone, a serotonin antagonist, for four weeks. Alterations in the mRNA expression levels of these candidate genes in the hypothalamus were also analyzed. We hypothesized that risperidone treatment might alter both hypothalamic and circulating levels of neuropeptides through serotonergic antagonism, resulting in weight gain. Gene expression studies revealed that the mRNA expression levels of proopiomelanocortin (POMG), AgRP, and NPY decreased as well as their plasma levels, except for NPY. Unexpectedly, CART mRNA levels increased when their plasma levels decreased. Because POMC neurons express the serotonin receptor (5HT(2c)), the serotonergic antagonism of risperidone on POMC neurons may cause an increase in appetite and thus increase food consumption even in a short-term trial in rats.


Determination of hypothalamic neuropeptide levels involved in appetite regulation in atypical antipsychotic drug, risperidone treatment
Kurşungöz, Canan; Yanık, Tülin; Department of Biology (2012)
Although the use of atypical antipsychotic drugs is successful in the treatment of schizophrenia, they cause complications in the long term use that is mainly weight gain. In this study, circulating levels of hypothalamic neuropeptides/hormones, which are related to appetite regulation; neuropeptide Y (NPY), alpha melanocyte stimulating hormone (α-MSH), cocaine and amphethamine regulated transcript (CART) and plus leptin in male schizophrenic patients who were treated with an atypical antipsychotic drug, ri...
Effects of olanzapine on serum protein phosphorylation patterns in patients with schizophrenia
Jaros, Julian A.; Rahmoune, Hassan; Wesseling, Hendrik; Leweke, F. Markus; Özcan Kabasakal, Süreyya; Guest, Paul C.; Bahn, Sabine (2015-10-01)
Purpose Previous studies have shown that blood serum phosphoproteins are altered in schizophrenia patients in comparison to controls. However, it is not known whether phosphoproteins are also changed in response to treatment with antipsychotics.
Effects of chronic diazepam treatment and withdrawal on avoidance behavior
Ayvasik, B; Zagli, U; Palaoglu, O; Soygur, H; Ayhan, IH (1999-06-01)
The present study was designed to evaluate the effects of chronic diazepam (DZ) treatment with low doses and diazepam withdrawal on the two-way shuttle-box avoidance performance in rats. After 24 rats were randomly assigned into three groups (I mg/kg DZ, 2 mg/kg DZ and control groups), all animals were trained to avoid from an electrical foot shock (0.8 mA) delivered through the grid floor by crossing to the other compartment of the box. Following the avoidance training, the first group received I mg/kg DZ ...
Alterations of hypothalamic neuropeptides involved in food intake and appetite in olanzapine monotherapy
Sezlev, Deniz; Yanık, Tülin; Department of Biology (2012)
The mechanism of weight gain due to treatment with olanzapine, a serotonin receptor antagonist, has not been fully understood. Weight gain and food intake are under the control of neuropeptides/hormones, POMC (proopiomelanocortin), CART (cocaine and amphetamine regulated transcript), AgRP (Agouti-related peptide) and NPY (neuropeptide Y) that are synthesized and secreted from the arcuate nucleus (ARC) of hypothalamus. In this study, the altereration of the ARC neuropeptide/hormone levels both in humans and ...
Impacts of olanzapine coupled with or without metformin administration on the expression of cannabinoid and melanocortin receptors in rats
Jacob Alis, Aditya Kemal; Yanık, Tülin; Department of Biochemistry (2017)
Secondary generation antipsychotics (SGA) were lauded as an improvement over first generation antipsychotics (FGA) in terms of both efficacies and reduced metabolic side effects such as obesity and diabetic phenotypes (1). However, SGAs were still plagued by a plethora of aforementioned metabolic side effects, albeit at reduced severity compared to the FGAs. While the side effects of SGAs had been extensively investigated through different experiments, the exact mechanism of the SGAs on the metabolic disord...
Citation Formats
C. Kursungoz, M. AK, and T. Yanık, “Effects of risperidone treatment on the expression of hypothalamic neuropeptide in appetite regulation in Wistar rats,” BRAIN RESEARCH, pp. 146–155, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/43163.