Study Objectives: The atypical antipsychotic olanzapine is used effectively for treating symptoms of schizophrenia and bipolar disorder. Unwanted effects of olanzapine include slowing of the electroencephalogram (EEG) during wakefulness and increased circulating levels of leptin. The mechanisms underlying the desired and undesired effects of olanzapine are poorly understood. Sleep and wakefulness are modulated by acetylcholine (ACh) in the prefrontal cortex, and leptin alters cholinergic transmission. This study tested the hypothesis that olanzapine interacts with leptin to regulate ACh release in the prefrontal cortex.
Design: Within/between subjects.
Setting: University of Michigan.
Patients Or Participants: Adult male C57BL/6J (B6) mice (n = 33) and B6.V-Lep(ob) (leptin-deficient) mice (n = 31).
Interventions: Olanzapine was delivered to the prefrontal cortex by microdialysis. Leptin-replacement in leptin-deficient mice was achieved using subcutaneous micro-osmotic pumps.
Measurements And Results: Olanzapine caused a concentration-dependent increase in ACh release in B6 and leptin-deficient mice. Olanzapine was 230-fold more potent in leptin-deficient than in B6 mice for increasing ACh release, yet olanzapine caused a 51% greater ACh increase in B6 than in leptin-deficient mice. Olanzapine had no effect on recovery time from general anesthesia. Olanzapine increased EEG power in the delta (0.5-4 Hz) range. Thus, olanzapine dissociated the normal coupling between increased cortical ACh release, increased behavioral arousal, and EEG activation. Leptin replacement significantly enhanced (75%) the olanzapine-induced increase in ACh release.
Conclusion: Replacing leptin by systemic administration restored the olanzapine-induced enhancement of ACh release in the prefrontal cortex of leptin-deficient mouse.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3274332 | PMC |
http://dx.doi.org/10.5665/sleep.1686 | DOI Listing |
N Engl J Med
December 2024
From the Department of Pediatrics and Child Health, Desmond Tutu TB Centre, Stellenbosch University, Stellenbosch (A.C.H., S.E.P., H.S.S., A.G.-P., E.B., A.-M.D., S.N., J.A.S., L. Frigati), the Perinatal HIV Research Unit (N.A.M.) and the Faculty of Health Sciences, Wits Research Health Institute (L. Fairlie), University of the Witwatersrand, and Isango Lethemba TB Research Unit, Port Elizabeth, Wits Health Consortium (F.C.), Johannesburg, and the Tuberculosis and HIV Investigative Network, Durban (S.S.) - all in South Africa; the Johns Hopkins Center for TB Research, Baltimore (N.A.M.); the Medical Research Council Clinical Trials Unit at University College London (J.B., D.M.G., C.M., C.L., R.T., T.D.) and the Department of Infectious Disease, Imperial College London (J.A.S.) - both in London; the Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison (A.G.P.); and the Division of Microbiology, Department of Laboratory Medicine, Centre Hospitalier Universitaire Sainte-Justine, and the Department of Microbiology, Immunology, and Infectious Diseases, Faculty of Medicine, University of Montreal - both in Montreal (A.-M.D.).
Background: Worldwide, approximately 2 million children younger than 15 years of age are infected with multidrug-resistant (MDR) , with MDR tuberculosis developing in approximately 30,000 annually. Evidence from randomized, controlled trials on tuberculosis preventive treatment in persons exposed to MDR tuberculosis is lacking.
Methods: In this community-based, multisite, double-blind, cluster-randomized, placebo-controlled trial in South Africa, we assessed the efficacy and safety of levofloxacin as preventive treatment in children with household exposure to an adult with bacteriologically confirmed MDR pulmonary tuberculosis.
Sci Adv
December 2024
Department of Neuroscience and Experimental Therapeutics, College of Medicine, Texas A&M University Health Science Center, Bryan, TX, USA.
Striatal cholinergic interneurons (CINs) are key to regulating behavioral flexibility, involving both extinguishing learned actions and adopting new ones. However, the mechanisms driving these processes remain elusive. In this study, we initially demonstrate that chronic alcohol consumption disrupts the burst-pause dynamics of CINs and impairs behavioral flexibility.
View Article and Find Full Text PDFToxicol Appl Pharmacol
December 2024
Library of Jiaying University, Meizhou, China.
Diabetic gastroparesis (DGP), a prevalent complication of diabetes, is characterized by delayed gastric emptying and inflammation. The dorsal motor nucleus of the vagus (DMV) plays a crucial role in modulating gastric function via the vagus nerve. Neuregulin 1 (NRG1), which is present in the DMV and influences the autonomic nervous system, has an unclear role in DGP.
View Article and Find Full Text PDFbioRxiv
December 2024
Department of Pharmacology, Physiology & Neuroscience, University of South Carolina School of Medicine, Columbia, South Carolina, 29208, USA.
While the basolateral amygdala (BLA) is critical in the consolidation of emotional memories, mechanisms underlying memory consolidation in this region are not well understood. In the hippocampus, memory consolidation depends upon network signatures termed sharp wave ripples (SWR). These SWRs largely occur during states of awake rest or slow wave sleep and are inversely correlated with cholinergic tone.
View Article and Find Full Text PDFIntroduction: The Efferent Vestibular System (EVS) originates in brainstem Efferent Vestibular Nuclei (EVN) and modifies afferent vestibular signals at their source, in peripheral vestibular organs. Recent evidence suggests that EVS is also involved in the development of motion sickness symptoms, including vertigo and nausea, but the underlying mechanism is unknown. One possible link between EVN and motion sickness symptoms is through the neuropeptide calcitonin gene-related peptide (CGRP).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!