Presynaptic inhibitory action of morphine on excitatory synaptic transmission in rat SON neurons in brain slices
- Author:
- No author available
- Journal Title:
- JOURNAL OF THE FOURTH MILITARY MEDICAL UNIVERSITY
- Issue:
- 5
- DOI:
- 10.3321/j.issn:1000-2790.2001.05.004
- Key Word:
- 视上核;脑片;全细胞记录;吗啡;突触传递
Abstract： AIM To observe the effects of morphine on the excita tory postsynaptic currents (EPSCs) and miniature EPSCs (mEPSCs) in rat supraoptic nucleus (SON) neurons and to determine its synaptic mechanism. METHODS Using whole-cell voltage-clamp recording technique in brain slices, the EPSCs and mEPSCs of rat SON neurons were recorded, respectively. RESULTS 20 μmol*L -1 morphine decreased the frequency of EPSCs and mEPSCs (EPSCs by 65%, mEPSCs by 45%), and decreased the amplitude of EPSCs by 44% in all SON neurons, but had no effect on the amplitude distribution of mEPSCs. CONCLUSION Morphine in hibits the excitatory transmissions via presynaptic mechanisms in SON neurons from rat brai n slices.
- [1]L P, Renaud,C W, Bourque.Neurophysiology and neuropharmacology of hypothalamic magnocellular neurons secreting vasopressin and oxytocin.[J].1991,36(2).
- [2]J A, Russell,J E, Coombes,G, Leng,etc.Morphine tolerance and inhibition of oxytocin secretion by kappa-opioids acting on the rat neurohypophysis.[J].1993,469.
- [3]Capogna M,G<img src="http://onlinelibrarystatic.wiley.com/undisplayable_characters/0000e4.gif" alt="[a WITH DIAERESIS]" />hwiler B H,Thompson S M.Mechanism of mu-opioid receptor-mediated presynaptic inhibition in the rat hippocampus in vitro.[J].1993,470(1).
- [4]K M, Pumford,G, Leng,J A, Russell.Morphine actions on supraoptic oxytocin neurones in anaesthetized rats: tolerance after i.c.v. morphine infusion.[J].1991,440.
- [5]Tasker JG,Schrader LA.Presynaptic modulation by metabotropic glutamate receptors of excitatory and inhibitory synaptic inputs to hypothalamic magnocellular neurons.[J].1997,77(2).
- [6]Russell JA,Leng G,Bicknell RJ.Opioid tolerance and dependence in the magnocellular oxytocin system: a physiological mechanism?[J].1995,80(3).
- [7]Luckman SM,Kendrick K,Onaka T,etc.Presynaptic actions of morphine: blockade of cholecystokinin-induced noradrenaline release in the rat supraoptic nucleus.[J].1995,482(Pt.1).
- [8]Mike Ludwig,Michael F. Callahan,Inga Neumann,etc.Systemic Osmotic Stimulation Increases Vasopressin and Oxytocin Release Within the Supraoptic Nucleus[J].1994,6(4).
- [9]K. Inenaga,H. Imura,N. Yanaihara,etc.Kappa-Selective Opioid Receptor Agonists Leumorphin and Dynorphin Inhibit Supraoptic Neurons in Rat Hypothalamic Slice Preparations[J].1990,2(3).
- [10]Rainer Landgraf,Inga Neumann,Quentin J. Pittman.Septal and Hippocampal Release of Vasopressin and Oxytocin during Late Pregnancy and Parturition in the Rat[J].1991,54(4).