Pituitary lactotrophs fire action potentials spontaneously and the associated voltage-gated calcium influx is sufficient to maintain high prolactin release. Here we studied the role of hyperpolarization-activated cation channels in pacemaking activity, calcium signaling, and prolactin secretion in these cells. A slowly developing and hyperpolarization-activated inward current was identified but only in a fraction of lactotrophs. The current was blocked by ZD7288, a relatively specific blocker of these channels. However, the pacemaking activity increased in ZD7288-treated cells independently of the presence of this current. This in turn facilitated voltage-gated calcium influx and transiently stimulated prolactin secretion. Sustained ZD7288 application in concentrations that are commonly used to block the hyperpolarization-activated cation channels inhibited hormone release at elevated intracellular calcium concentrations. Agonist and Bay K 8644-stimulated prolactin release was also inhibited by ZD7288, indicating that this compound attenuates the exocytotic pathway downstream of calcium influx.
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http://dx.doi.org/10.1016/j.bbrc.2006.05.194 | DOI Listing |
Acta Physiol (Oxf)
February 2025
Department of Biochemistry, Cell and Systems Biology, Institute of Systems, Molecular and Integrative Biology, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK.
Aim: Long QT syndrome (LQTS) and catecholaminergic polymorphism ventricular tachycardia (CPVT) are inherited cardiac disorders often caused by mutations in ion channels. These arrhythmia syndromes have recently been associated with calmodulin (CaM) variants. Here, we investigate the impact of the arrhythmogenic variants D131E and Q135P on CaM's structure-function relationship.
View Article and Find Full Text PDFNat Commun
January 2025
NMR Based Structural Biology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
Aggregation intermediates play a pivotal role in the assembly of amyloid fibrils, which are central to the pathogenesis of neurodegenerative diseases. The structures of filamentous intermediates and mature fibrils are now efficiently determined by single-particle cryo-electron microscopy. By contrast, smaller pre-fibrillar α-Synuclein (αS) oligomers, crucial for initiating amyloidogenesis, remain largely uncharacterized.
View Article and Find Full Text PDFColloids Surf B Biointerfaces
January 2025
State Key Laboratory of Precision Manufacturing for Extreme Service Performance, College of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China; Jiangxi Province Key Laboratory of Additive Manufacturing of Implantable Medical Device, Jiangxi University of Science and Technology, Nanchang 330013, China. Electronic address:
Electrical stimulation displayed tremendous potential in promoting nerve regeneration. However, the current electrical stimulation therapy required complex traversing wires and external power sources, which significantly limited its practical application. Herein, a self-powered nerve scaffold based on primary battery principle was gradient printed by laser additive manufacturing technique.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
School of Food Science and Engineering, South China University of Technology, Guangzhou 510641, China.
The involvement of neurons in the peripheral nervous system is crucial for bone regeneration. Mimicking extracellular matrix cues provides a more direct and effective strategy to regulate neuronal activity and enhance bone regeneration. However, the simultaneous coupling of the intrinsic mechanical-electrical microenvironment of implants to regulate innervated bone regeneration has been largely neglected.
View Article and Find Full Text PDFSci Adv
January 2025
New Cornerstone Science Laboratory, CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety & CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology of China, Beijing 100190, China.
Deep brain stimulation technology enables the neural modulation with precise spatial control but requires permanent implantation of conduits. Here, we describe a photothermal wireless deep brain stimulation nanosystem capable of eliminating α-synuclein aggregates and restoring degenerated dopamine neurons in the substantia nigra to treat Parkinson's disease. This nanosystem (ATB NPs) consists of gold nanoshell, an antibody against the heat-sensitive transient receptor potential vanilloid family member 1 (TRPV1), and β-synuclein (β-syn) peptides with a near infrared-responsive linker.
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