Inhibition of Rho-kinase by fasudil contributes to the modulation of the synaptic plasticity response in the rat hippocampus

被引:0
作者
Ercan Babur [1 ]
Hatice Saray [1 ]
Cem Süer [1 ]
Nurcan Dursun [1 ]
机构
[1] Department of Physiology, Erciyes University Faculty of Medicine, Kayseri
关键词
Fasudil; Hippocampus; Protein Tau; ROCK; Synaptic plasticity;
D O I
10.1007/s00424-025-03078-4
中图分类号
学科分类号
摘要
Metaplasticity refers to an activity-dependent change in the physiological or biochemical state of neurons that changes their ability to generate subsequently induced synaptic plasticity, such as long-term potentiation (LTP) or long-term depression (LTD). Rho-kinases (ROCK) are known to be important for stable changes in synaptic strength, especially LTP. In this study, we investigated whether LTP inhibition in synapses primed with 1-Hz stimulation was affected by ROCK inhibition in young adult male rats. The study also examined the pattern of tau phosphorylation that occurs during metaplastic regulation, applying into perspective the phosphorylation of tau protein by ROCK. Field potentials consisting of an excitatory postsynaptic potential (fEPSP) and population spike (PS) were recorded from the granule cell layer of the hippocampal dentate gyrus (DG). Metaplastic LTP was induced by strong tetanic stimulation (HFS) of the lateral perforant path after a low-frequency stimulation (LFS) protocol. A glass micropipette was inserted into the granule cell layer of the ipsilateral dentate gyrus to record fEPSP and drug infusion. Drug infusion (saline, n = 8; fasudil, n = 8, 10 µM) was started after the 15-min baseline recording and lasted for 60 min. Total and phosphorylated tau levels were measured in the stimulated hippocampus, which was immediately removed after the electrophysiological recording. LFS prevented the induction of LTP in response to HFS and even produced synaptic LTD in the saline-infused group (83.8 ± 2.6% of the baseline), but moderate potentiation of fEPSP (121.1 ± 7.7% of the baseline) occurred at the end of recording in the experiments where fasudil infusion was performed. LFS caused a comparable early depression, and HFS resulted in a comparable potentiation of the PS amplitude in both groups. Granular cells of the DG failed to exhibit synaptic LTP inhibition in the presence of fasudil, and levels of total and phosphorylated GSK-3β and levels of phosphorylated tau (Ser396 and Ser202-Thr205) were found to be lower than those of the control group. Based on these findings, it can be concluded that pharmacological inhibition of ROCK results in impaired ability of dentate gyrus neurons to inhibit synaptic LTP, and this result is accompanied by decreased phosphorylation of GSK-3β and tau proteins. The negative effect of fasudil on neuronal function should not be neglected when evaluating its effects as a therapeutic agent for diseases. © The Author(s) 2025.
引用
收藏
页码:787 / 796
页数:9
相关论文
共 32 条
  • [1] Abraham W.C., Bear M.F., Metaplasticity: the plasticity of synaptic plasticity, Trends Neurosci, 19, 4, pp. 126-130, (1996)
  • [2] Antonov I., Kandel E.R., Hawkins R.D., Presynaptic and postsynaptic mechanisms of synaptic plasticity and metaplasticity during intermediate-term memory formation in aplysia, J Neurosci, 30, 16, pp. 5781-5791, (2010)
  • [3] Bear M.F., Mechanism for a sliding synaptic modification threshold, Neuron, 15, 1, pp. 1-4, (1995)
  • [4] Bortolotto Z.A., Et al., An analysis of the stimulus requirements for setting the molecular switch reveals a lower threshold for metaplasticity than synaptic plasticity, Neuropharmacology, 55, 4, pp. 454-458, (2008)
  • [5] Cai J.W., Et al., Solution-processed polymer memcapacitors with stimulus-controlled and evolvable synaptic functionalities: from short-term plasticity to long-term plasticity to metaplasticity, ACS Appl Mater Interfaces, (2024)
  • [6] Costello D.A., Et al., Brain deletion of insulin receptor substrate 2 disrupts hippocampal synaptic plasticity and metaplasticity, PLoS One, 7, 2, (2012)
  • [7] Feng Y.B., Et al., Rho kinase (ROCK) inhibitors and their therapeutic potential, J Med Chem, 59, 6, pp. 2269-2300, (2016)
  • [8] Fujii S., Et al., The long-term suppressive effect of prior activation of synaptic inputs by low-frequency stimulation on induction of long-term potentiation in CA1 neurons of guinea pig hippocampal slices, Exp Brain Res, 111, 3, pp. 305-312, (1996)
  • [9] Gentry E.G., Et al., Rho kinase inhibition as a therapeutic for progressive supranuclear palsy and corticobasal degeneration, J Neurosci, 36, 4, pp. 1316-1323, (2016)
  • [10] Grey K.B., Burrell B.D., Co-induction of LTP and LTD and its regulation by protein kinases and phosphatases, J Neurophysiol, 103, 5, pp. 2737-2746, (2010)