Skip to main content
Article thumbnail
Location of Repository

Emergent synchronous bursting of oxytocin neuronal network

By Enrico Rossoni, Jianfeng Feng, Brunello Tirozzi, David Brown, G. (Gareth) Leng and François Moos

Abstract

When young suckle, they are rewarded intermittently with a let-down of milk that results from reflex secretion of the\ud hormone oxytocin; without oxytocin, newly born young will die unless they are fostered. Oxytocin is made by magnocellular\ud hypothalamic neurons, and is secreted from their nerve endings in the pituitary in response to action potentials (spikes) that\ud are generated in the cell bodies and which are propagated down their axons to the nerve endings. Normally, oxytocin cells\ud discharge asynchronously at 1–3 spikes/s, but during suckling, every 5 min or so, each discharges a brief, intense burst of\ud spikes that release a pulse of oxytocin into the circulation. This reflex was the first, and is perhaps the best, example of a\ud physiological role for peptide-mediated communication within the brain: it is coordinated by the release of oxytocin from\ud the dendrites of oxytocin cells; it can be facilitated by injection of tiny amounts of oxytocin into the hypothalamus, and it\ud can be blocked by injection of tiny amounts of oxytocin antagonist. Here we show how synchronized bursting can arise in a\ud neuronal network model that incorporates basic observations of the physiology of oxytocin cells. In our model, bursting is\ud an emergent behaviour of a complex system, involving both positive and negative feedbacks, between many sparsely\ud connected cells. The oxytocin cells are regulated by independent afferent inputs, but they interact by local release of\ud oxytocin and endocannabinoids. Oxytocin released from the dendrites of these cells has a positive-feedback effect, while\ud endocannabinoids have an inhibitory effect by suppressing the afferent input to the cells

Topics: QP
Publisher: Public Library of Science
Year: 2008
OAI identifier: oai:wrap.warwick.ac.uk:4433

Suggested articles

Citations

  1. (2006). A model for the pulsatile secretion of gonadotropinreleasing hormone from synchronized hypothalamic. doi
  2. (1994). A rise in the intracellular Ca 2+ concentration of isolated rat supraoptic cells in response to oxytocin. doi
  3. (2006). A study of the role of neuro-glial remodeling in the oxytocin system at lactation. doi
  4. (1993). Action of endogenous oxytocin within the paraventricular or supraoptic nuclei: A powerful link in the regulation of the bursting pattern of oxytocin neurons during the milk-ejection reflex in rats. doi
  5. (2005). Autofeedback effects of progressively rising oxytocin concentrations of supraoptic oxytocin neuronal activity in slices from lactating rats. doi
  6. (1985). Calcium-dependent potassium conductance in rat supraoptic nucleus neurosecretory neurons.
  7. (1989). Dendrites of hypothalamic magnocellular neurons release neurohypophysial peptides by exocytosis. doi
  8. (2006). Dendritic peptidic release and peptide dependent behaviours. doi
  9. (2004). Dendritically released transmitters cooperate via autocrine and retrograde actions to inhibit afferent excitation in rat brain. doi
  10. (1987). Electrical stimulations of perifused magnocellular nuclei in vitro elicit Ca2+-dependent, tetrodotoxininsensitive release of oxytocin and vasopressin. doi
  11. (1994). Electrophysiological characteristics of immunochemically identified rat oxytocin and vasopressin neurones in vitro. doi
  12. (1974). Electrophysiological evidence for the activation of supraoptic neurons during the release of oxytocin. doi
  13. (2005). Enhancement of calcium-dependent afterpotentials in oxytocin neurons of the rat supraoptic nucleus during lactation. doi
  14. (1998). Evidence for a hypothalamic oxytocin-sensitive pattern generating network governing oxytocin neurons in vitro.
  15. (1995). GABA-induced facilitation of the periodic bursting activity of oxytocin neurons in suckled rats. doi
  16. (2000). Gamma rhythms and beta rhythms have different synchronization properties. doi
  17. (1991). Identification of oxytocin cells in the rat supraoptic nucleus by their response to cholecystokinin injection. doi
  18. (2006). Information processing in the hypothalamus: Peptides and analogue computation. doi
  19. (2002). Intracellular calcium stores regulate activity-dependent neuropeptide release from dendrites. doi
  20. (2003). Luthi A
  21. (1984). Method for quantitating the molecular content of a subcellular organelle: hormone and neurophysin content of newly formed and aged neurosecretory granules. doi
  22. (2004). Milk ejection burst-like electrical activity evoked in supraoptic oxytocin neurons in slices from lactating rats. doi
  23. (2000). Multispikes and synchronization in a large neural network with temporal delays. doi
  24. (1997). Onset of bursting in oxytocin cells in suckled rats. doi
  25. (2004). Oxytocin neurones are recruited into co-ordinated fluctuations of firing before bursting in the rat. doi
  26. (1994). Oxytocin receptors on oxytocin neurones: Histoautoradiographic detection in the lactating rat. doi
  27. (2002). Oxytocin-secreting neurons: A physiological model of morphological neuronal and glial plasticity in the adult hypothalamus. doi
  28. (2005). Pervasive social deficits, but normal parturition, in oxytocin receptor-deficient mice. doi
  29. (2004). Phasic spike patterning in rat supraoptic neurones in vivo and in vitro. doi
  30. (1999). Physiological pathways regulating the activity of magnocellular neurosecretory cells. doi
  31. (1996). Postsynaptic mechanism of depression of gabaergic synapses by oxytocin in the supraoptic nucleus in immature rat. doi
  32. (1984). Release of oxytocin and vasopressin by magnocellular nuclei in vitro: specific facilitatory effect of oxytocin on its own release. doi
  33. (1989). Release of oxytocin within the supraoptic nucleus during the milk ejection reflex in rats. doi
  34. (2001). Responses of magnocellular neurons to osmotic stimulation involves co-activation of excitatory and inhibitory input: an experimental and theoretical analysis.
  35. (1998). Synchronization of Golgi and granule cell firing in a detailed network model of the cerebellar granule cell layer.
  36. (2000). Synchrony generation in recurrent networks with frequency-dependent synapses.
  37. (2003). The magnocellular oxytocin system. The fount of maternity: adaptations in pregnancy. doi
  38. (1973). The milk-ejection reflex of the rat: a 20- to 40-fold acceleration in the firing of paraventricular neurones during oxytocin release. doi
  39. (1997). The origins and significance of pulsatility in hormone secretion from the pituitary. doi
  40. (1986). The regulation of the milk-ejection reflex in the rat. doi
  41. (1985). The role of patterned burst and interburst interval on the excitation-coupling mechanism in the isolated rat neural lobe. doi
  42. (2000). The variability of basal action potential firing is positively correlated with bursting in hypothalamic oxytocin neurones. doi
  43. (1977). Ultrastructural morphometry of the rat neurohypophysis.

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.