Lab personnel
- Mehwish Abbassi PhD Student
- Dhananjie Chandrasekera Assistant Research Fellow
- Caroline Focke PhD Student
- Dr Karl Iremonger Senior Lecturer
- Dr Joon Kim Postdoctoral Fellow
- Shao Zheng BBiomedSc Honours student
Research interests
The hypothalamus is an area of the brain that contains neural circuits that are essential for survival. We are specifically interested in one part of the hypothalamus called the paraventricular nucleus (PVN). Neurons in the PVN are activated in response to many different types of stress and in turn release neuropeptides both within the brain and into the circulation to control the body’s stress response.
We use electrophysiology, imaging, optogenetics and other techniques to understand how neural circuits within the PVN function. We are specifically interested in determining how stress responsive neurons in the PVN process information and adapt across different physiological and behavioral states.
Research topics
- Control of corticotropin-releasing hormone (CRH) neuron excitability by retrograde neurotransmitters
- Chronic stress induced adaptations in hypothalamic brain circuits
- Imaging CRH neuron activity in vivo with genetically encoded calcium indicators
Selected publications
Bittar, T. P., Nair, B. B., Kim, J. S., Chandrasekera, D., Sherrington, A., & Iremonger, K. J. (2019). Corticosterone mediated functional and structural plasticity in corticotropin-releasing hormone neurons. Neuropharmacology. Advance online publication. doi: 10.1016/j.neuropharm.2019.02.017
Choi, J.-H., Jeong, Y.-M., Kim, S., Lee, B., Ariyasiri, K., Kim, H.-T., … Jamieson, B. B., Kim, J. S., Iremonger, K. J., … Kim, C.-H. (2018). Targeted knockout of a chemokine-like gene increases anxiety and fear responses. PNAS, 115(5), e1041-e1050. doi: 10.1073/pnas.1707663115
Iremonger, K., & Gouws, J. (2018). Regulation of CRH neuronal network activity by noradrenergic stress signals. Proceedings of the 9th International Congress of Neuroendocrinology (ICN). (pp. 149). Retrieved from http://www.icn2018.org/
Focke, C., & Iremonger, K. (2018). Investigating the natural rhythms if CRH neuron excitability over the day. Proceedings of the 9th International Congress of Neuroendocrinology (ICN). (pp. 155). Retrieved from http://www.icn2018.org/
Kim, J., & Iremonger, K. (2018). Stress familiarity but not fast negative feedback robustly tunes stress neuron output. Proceedings of the 9th International Congress of Neuroendocrinology (ICN). (pp. 150-151). Retrieved from http://www.icn2018.org/
Jamieson, B. B., Nair, B. B., & Iremonger, K. J. (2017). Regulation of hypothalamic corticotropin‐releasing hormone neurone excitability by oxytocin. Journal of Neuroendocrinology, 29(11), e12532. doi: 10.1111/jne.12532
Iremonger, K. J., Porteous, R., & Herbison, A. E. (2017). Spike and neuropeptide-dependent mechanisms control GnRH neuron nerve terminal Ca2+ over diverse time scales. Journal of Neuroscience, 37(12), 3342-3351. doi: 10.1523/jneurosci.2925-16.2017
Clarkson, J., Han, S. Y., Piet, R., McLennan, T., Kane, G. M., Ng, J., Porteous, R. W., Kim, J. S., … Iremonger, K. J., & Herbison, A. E. (2017). Definition of the hypothalamic GnRH pulse generator in mice. PNAS, 114(47), E10216-E10223. doi: 10.1073/pnas.1713897114
Nair, B., Khant Aung, Z., Porteous, R., Prescott, M., Ng, J., Yip, S., Augustine, R., Glendining, K., Bouwer, G., Kim, J., Jenkins, D., Silva, M., Brown, C., Campbell, R., Jasoni, C., Bunn, S., Anderson, G., Grattan, D., Herbison, A., & Iremonger, K. (2017). Impact of chronic stress on the neuroendocrine axis in the mouse. In B. Leitch (Ed.), Proceedings of the 35th International Australasian Winter Conference on Brain Research. (pp. 49). AWCBR. Retrieved from http://www.otago.ac.nz/awcbr/index.html
Kim, J. S., & Iremonger, K. J. (2017). Rapid modulation of stress neuron activity dynamics. In B. Leitch (Ed.), Proceedings of the 35th International Australasian Winter Conference on Brain Research. (pp. 31). AWCBR. Retrieved from http://www.otago.ac.nz/awcbr/index.html
Gouws, J. M., & Iremonger, K. J. (2017). Regulation of CRH neuronal network activity by noradrenergic stress signals. In B. Leitch (Ed.), Proceedings of the 35th International Australasian Winter Conference on Brain Research. (pp. 55). AWCBR. Retrieved from http://www.otago.ac.nz/awcbr/index.html
Gouws, J., & Iremonger, K. (2017). Determining sexually dimorphic changes in CRH neural network activity induced by stress hormones. New Zealand Medical Journal, 130(1461), (pp. 89). Retrieved from http://www.nzma.org.nz/journal
Iremonger, K. J., & Bains, J. S. (2016). Asynchronous presynaptic glutamate release enhances neuronal excitability during the post-spike refractory period. Journal of Physiology, 594(4), 1005-1015. doi: 10.1113/JP271485
Iremonger, K. J., & Bittar, T. (2016). Corticosteriod induced functional and structural plasticity of hypothalamic corticotropin-releasing hormone (CRH) neurons. In B. Leitch (Ed.), Proceedings of the 34th International Australasian Winter Conference on Brain Research. (pp. 27). AWCBR. Retrieved from http://www.otago.ac.nz/awcbr
Iremonger, K. J., Bittar, T., & Nair, B. (2016). Morphological analysis of hypothalamic corticotropin-releasing hormone (CRH) neurons. Proceedings of the Society for Neuroscience 46th Annual Meeting. 814.09/QQ13. SfN. Retrieved from https://www.sfn.org/
Kim, J., Anderson, G. M., & Iremonger, K. J. (2016). RFRP-3 actions on corticotropin-releasing hormone neurons. Proceedings of the Society for Neuroscience 46th Annual Meeting. 813.13/PP15. SfN. Retrieved from https://www.sfn.org
Iremonger, K. J., & Herbison, A. E. (2015). Elucidating the structure and function of Gonadotropin-Releasing Hormone (GnRH) neuron dendrites. In W. E. Armstrong & J. G. Tasker (Eds.), Neurophysiology of neuroendocrine neurons. (pp. 273-300). Chichester, UK: Wiley Blackwell. doi: 10.1002/9781118606803.ch12
Iremonger, K. J., & Herbison, A. E. (2015). Multitasking in gonadotropin-releasing hormone neuron dendrites. Neuroendocrinology, 102(1-2), 1-7. doi: 10.1159/000368364
Iremonger, K. (2015, June). Long lasting calcium elevations in nerve terminals driven by brief neuropeptide signals. Verbal presentation at the 9th Annual Brain Health Research Centre Conference: Science for a Healthy Brain, Dunedin, New Zealand.
Jamieson, B. B., & Iremonger, K. J. (2015, August-September). Modulation of GABAergic synaptic input to CRH neurons by oxytocin. Verbal presentation at the Medical Sciences Congress (MedSci), Queenstown, New Zealand.
Iremonger, K. (2015, June). Building blocks of the brain: New insights into how our brains work. University of Otago Winter Lecture Series. Wellington, New Zealand. [Public Lecture].
Iremonger, K. (2015, June). Building blocks of the brain: New insights into how our brains work. University of Otago Winter Lecture Series. Auckland, New Zealand. [Public Lecture].
Hsu, P., Herbison, A., & Iremonger, K. (2014). Impact of chronic stress on the dendritic structure of GnRH neurons in the mouse. Proceedings of the Medical Sciences Congress (MedSci). (pp. 38). Retrieved from http://www.physoc.org.nz/meetings/archive/medsci-2014-abstracts
Iremonger, K. J., & Herbison, A. E. (2014). Regulation of GnRH neuron nerve terminal excitability. In B. Leitch & J. Shemmell (Eds.), Proceedings of the 32nd International Australasian Winter Conference on Brain Research. 32, (pp. 27). AWCBR. Retrieved from https://web.psy.otago.ac.nz/awcbr/proceedings.html
Constantin, S., Iremonger, K. J., & Herbison, A. E. (2013). In vivo recordings of GnRH neuron firing reveal heterogeneity and dependence upon GABAA receptor signaling. Journal of Neuroscience, 33(22), 9394-9401. doi: 10.1523/jneurosci.0533-13.2013
Other Research Output
Iremonger, K. (2015, June). Building blocks of the brain: New insights into how our brains work. University of Otago Winter Lecture Series. Wellington, New Zealand. [Public Lecture].
Iremonger, K. (2015, June). Building blocks of the brain: New insights into how our brains work. University of Otago Winter Lecture Series. Auckland, New Zealand. [Public Lecture].
Chapter in Book - Research
Iremonger, K. J., & Herbison, A. E. (2015). Elucidating the structure and function of Gonadotropin-Releasing Hormone (GnRH) neuron dendrites. In W. E. Armstrong & J. G. Tasker (Eds.), Neurophysiology of neuroendocrine neurons. (pp. 273-300). Chichester, UK: Wiley Blackwell. doi: 10.1002/9781118606803.ch12
Journal - Research Article
Bittar, T. P., Nair, B. B., Kim, J. S., Chandrasekera, D., Sherrington, A., & Iremonger, K. J. (2019). Corticosterone mediated functional and structural plasticity in corticotropin-releasing hormone neurons. Neuropharmacology. Advance online publication. doi: 10.1016/j.neuropharm.2019.02.017
Choi, J.-H., Jeong, Y.-M., Kim, S., Lee, B., Ariyasiri, K., Kim, H.-T., … Jamieson, B. B., Kim, J. S., Iremonger, K. J., … Kim, C.-H. (2018). Targeted knockout of a chemokine-like gene increases anxiety and fear responses. PNAS, 115(5), e1041-e1050. doi: 10.1073/pnas.1707663115
Jamieson, B. B., Nair, B. B., & Iremonger, K. J. (2017). Regulation of hypothalamic corticotropin‐releasing hormone neurone excitability by oxytocin. Journal of Neuroendocrinology, 29(11), e12532. doi: 10.1111/jne.12532
Clarkson, J., Han, S. Y., Piet, R., McLennan, T., Kane, G. M., Ng, J., Porteous, R. W., Kim, J. S., … Iremonger, K. J., & Herbison, A. E. (2017). Definition of the hypothalamic GnRH pulse generator in mice. PNAS, 114(47), E10216-E10223. doi: 10.1073/pnas.1713897114
Iremonger, K. J., Porteous, R., & Herbison, A. E. (2017). Spike and neuropeptide-dependent mechanisms control GnRH neuron nerve terminal Ca2+ over diverse time scales. Journal of Neuroscience, 37(12), 3342-3351. doi: 10.1523/jneurosci.2925-16.2017
Iremonger, K. J., & Bains, J. S. (2016). Asynchronous presynaptic glutamate release enhances neuronal excitability during the post-spike refractory period. Journal of Physiology, 594(4), 1005-1015. doi: 10.1113/JP271485
Iremonger, K. J., & Herbison, A. E. (2015). Multitasking in gonadotropin-releasing hormone neuron dendrites. Neuroendocrinology, 102(1-2), 1-7. doi: 10.1159/000368364
Constantin, S., Iremonger, K. J., & Herbison, A. E. (2013). In vivo recordings of GnRH neuron firing reveal heterogeneity and dependence upon GABAA receptor signaling. Journal of Neuroscience, 33(22), 9394-9401. doi: 10.1523/jneurosci.0533-13.2013
Iremonger, K. J., Wamsteeker Cusulin, J. I., & Bains, J. S. (2013). Changing the tune: Plasticity and adaptation of retrograde signals. Trends in Neurosciences, 36(8), 471-479. doi: 10.1016/j.tins.2013.04.007
Chen, X., Iremonger, K., Herbison, A., Kirk, V., & Sneyd, J. (2013). Regulation of electrical bursting in a spatiotemporal model of a GnRH neuron. Bulletin of Mathematical Biology, 75(10), 1941-1960. doi: 10.1007/s11538-013-9877-7
Herde, M. K., Iremonger, K. J., Constantin, S., & Herbison, A. E. (2013). GnRH neurons elaborate a long-range projection with shared axonal and dendritic functions. Journal of Neuroscience, 33(31), 12689-12697. doi: 10.1523/JNEUROSCI.0579-13.2013
Constantin, S., Piet, R., Iremonger, K., Yeo, S. H., Clarkson, J., Porteous, R., & Herbison, A. E. (2012). GnRH neuron firing and response to GABA in vitro depend on acute brain slice thickness and orientation. Endocrinology, 153(8), 3758-3769. doi: 10.1210/en.2012-1126
Iremonger, K. J., & Herbison, A. E. (2012). Initiation and propagation of action potentials in gonadotropin-releasing hormone neuron dendrites. Journal of Neuroscience, 32(1), 151-158. doi: 10.1523/jneurosci.3739-11.2012
Iremonger, K. J., Kuzmiski, J. B., Baimoukhametova, D. V., & Bains, J. S. (2011). Dual regulation of anterograde and retrograde transmission by endocannabinoids. Journal of Neuroscience, 31(33), 12011-12020. doi: 10.1523/JNEUROSCI.2925-11.2011
Iremonger, K. J., Benediktsson, A. M., & Bains, J. S. (2010). Glutamatergic synaptic transmission in neuroendocrine cells: Basic principles and mechanisms of plasticity. Frontiers in Neuroendocrinology, 31(3), 296-306. doi: 10.1016/j.yfrne.2010.03.002
Iremonger, K. J., Constantin, S., Liu, X., & Herbison, A. E. (2010). Glutamate regulation of GnRH neuron excitability. Brain Research, 1364, 35-43. doi: 10.1016/j.brainres.2010.08.071
Iremonger, K. J., & Bains, J. S. (2009). Retrograde opioid signaling regulates glutamergic transmission in the hypothalamus. Journal of Neuroscience, 29(22), 7349-7358. doi: 10.1523/JNEUROSCI.0381-09.2009
Gordon, G. R. J., Iremonger, K. J., Kantevari, S., Ellis-Davies, G. C. R., MacVicar, B. A., & Bains, J. S. (2009). Astrocyte-mediated distributed plasticity at hypothalamic glutamate synapses. Neuron, 64, 391-403. doi: 10.1016/j.neuron.2009.10.021
Iremonger, K. J., & Bains, J. S. (2008). Dynamic synapses in the hypothalamic-neurohypophyseal system. Progress in Brain Research, 170, 119-128. doi: 10.1016/S0079-6123(08)00411-1
Iremonger, K. J., & Bains, J. S. (2007). Integration of asynchronously released quanta prolongs the postsynaptic spike window. Journal of Neuroscience, 27(25), 6684-6691. doi: 10.1523/JNEUROSCI.0934-07.2007
Iremonger, K. J., Anderson, T. R., Hu, B., & Kiss, Z. H. T. (2006). Cellular mechanisms preventing sustained activation of cortex during subcortical high-frequency stimulation. Journal of Neurophysiology, 96, 613-621. doi: 10.1152/jn.00105.2006
Anderson, T. R., Hu, B., Iremonger, K., & Kiss, Z. H. T. (2006). Selective attenuation of afferent synaptic transmission as a mechanism of thalamic deep brain stimulation-induced tremor arrest. Journal of Neuroscience, 26(3), 841-850. doi: 10.1523/JNEUROSCI.3523-05.2006
Journal - Research Other
Iremonger, K. J. (2013). It takes more than one κ opioid receptor to inhibit a POMC neuron. Journal of Physiology, 591(7), 1595-1596. doi: 10.1113/jphysiol.2013.251637
Conference Contribution - Published proceedings: Abstract
Iremonger, K., & Gouws, J. (2018). Regulation of CRH neuronal network activity by noradrenergic stress signals. Proceedings of the 9th International Congress of Neuroendocrinology (ICN). (pp. 149). Retrieved from http://www.icn2018.org/
Kim, J., & Iremonger, K. (2018). Stress familiarity but not fast negative feedback robustly tunes stress neuron output. Proceedings of the 9th International Congress of Neuroendocrinology (ICN). (pp. 150-151). Retrieved from http://www.icn2018.org/
Focke, C., & Iremonger, K. (2018). Investigating the natural rhythms if CRH neuron excitability over the day. Proceedings of the 9th International Congress of Neuroendocrinology (ICN). (pp. 155). Retrieved from http://www.icn2018.org/
Nair, B., Khant Aung, Z., Porteous, R., Prescott, M., Ng, J., Yip, S., Augustine, R., Glendining, K., Bouwer, G., Kim, J., Jenkins, D., Silva, M., Brown, C., Campbell, R., Jasoni, C., Bunn, S., Anderson, G., Grattan, D., Herbison, A., & Iremonger, K. (2017). Impact of chronic stress on the neuroendocrine axis in the mouse. In B. Leitch (Ed.), Proceedings of the 35th International Australasian Winter Conference on Brain Research. (pp. 49). AWCBR. Retrieved from http://www.otago.ac.nz/awcbr/index.html
Gouws, J., & Iremonger, K. (2017). Determining sexually dimorphic changes in CRH neural network activity induced by stress hormones. New Zealand Medical Journal, 130(1461), (pp. 89). Retrieved from http://www.nzma.org.nz/journal
Gouws, J. M., & Iremonger, K. J. (2017). Regulation of CRH neuronal network activity by noradrenergic stress signals. In B. Leitch (Ed.), Proceedings of the 35th International Australasian Winter Conference on Brain Research. (pp. 55). AWCBR. Retrieved from http://www.otago.ac.nz/awcbr/index.html
Kim, J. S., & Iremonger, K. J. (2017). Rapid modulation of stress neuron activity dynamics. In B. Leitch (Ed.), Proceedings of the 35th International Australasian Winter Conference on Brain Research. (pp. 31). AWCBR. Retrieved from http://www.otago.ac.nz/awcbr/index.html
Iremonger, K. J., & Bittar, T. (2016). Corticosteriod induced functional and structural plasticity of hypothalamic corticotropin-releasing hormone (CRH) neurons. In B. Leitch (Ed.), Proceedings of the 34th International Australasian Winter Conference on Brain Research. (pp. 27). AWCBR. Retrieved from http://www.otago.ac.nz/awcbr
Kim, J., Anderson, G. M., & Iremonger, K. J. (2016). RFRP-3 actions on corticotropin-releasing hormone neurons. Proceedings of the Society for Neuroscience 46th Annual Meeting. 813.13/PP15. SfN. Retrieved from https://www.sfn.org
Iremonger, K. J., Bittar, T., & Nair, B. (2016). Morphological analysis of hypothalamic corticotropin-releasing hormone (CRH) neurons. Proceedings of the Society for Neuroscience 46th Annual Meeting. 814.09/QQ13. SfN. Retrieved from https://www.sfn.org/
Hsu, P., Herbison, A., & Iremonger, K. (2014). Impact of chronic stress on the dendritic structure of GnRH neurons in the mouse. Proceedings of the Medical Sciences Congress (MedSci). (pp. 38). Retrieved from http://www.physoc.org.nz/meetings/archive/medsci-2014-abstracts
Iremonger, K. J., & Herbison, A. E. (2014). Regulation of GnRH neuron nerve terminal excitability. In B. Leitch & J. Shemmell (Eds.), Proceedings of the 32nd International Australasian Winter Conference on Brain Research. 32, (pp. 27). AWCBR. Retrieved from https://web.psy.otago.ac.nz/awcbr/proceedings.html
Iremonger, K. J., & Herbison, A. E. (2013). Using genetically encoded calcium indicators to study the excitability of neurosecretory nerve terminals. In B. Leitch & J. Shemmell (Eds.), Proceedings of the 31st International Australasian Winter Conference on Brain Research. 31, (pp. 38). AWCBR. Retrieved from http://psy.otago.ac.nz/awcbr/Abstracts/Abstracts2013copy.html
Iremonger, K., Herde, M., Constantin, S., & Herbison, A. (2012). The dendron: A long-range neuronal projection with shared dendritic and axonal function. Proceedings of the Medical Sciences Congress (MedSci). (pp. 35-36). Retrieved from http://www.medscinz.co.nz/QRW2012%20MedSci%20Abstracts.pdf
Iremonger, K. J., Herde, M. K., Constantin, S., & Herbison, A. E. (2012). GnRH neurons project long-range dendrites to the median eminence to control neurosecretion. Proceedings of the Society for Neuroscience 42nd Annual Meeting. SfN. Retrieved from http://www.sfn.org/index.aspx?pagename=abstracts_am2012
Iremonger, K., & Herbison, A. E. (2011). Exploring dendritic physiology with combined imaging and electrophysiology. In B. Leitch (Ed.), Proceedings of the 29th International Australasian Winter Conference on Brain Research. 29, 9.4. AWCBR. Retrieved from http://psy.otago.ac.nz/awcbr/abstracts/abstracts2011.html
Iremonger, K. J., & Herbison, A. E. (2010). Back-propagating action potentials evoke faithful calcium transients in the dendrites of GnRH neurons. Proceedings of the Society for Neuroscience 40th Annual Meeting. SfN. Retrieved from http://www.abstractsonline.com/Plan/SSResults.aspx
Bains, J. S., Iremonger, K. J., & Kuzmiski, J. B. (2010). Dynamic interaction between retrograde signals regulates synaptic depression. Proceedings of the Society for Neuroscience Annual Meeting. Retrieved from http://www.sfn.org/index.aspx?pagename=abstracts_ampublications
Iremonger, K. J., Gordon, G. R. J., Kantevari, S., Ellis-Davies, G. C. R., MacVicar, B. A., & Bains, J. S. (2009). Astrocyte mediated distributed plasticity at glutamate synapses. Proceedings of the Society for Neuroscience Annual Meeting. Retrieved from http://www.sfn.org/index.aspx?pagename=abstracts_ampublications
Iremonger, K., & Bains, J. (2008). Control of synaptically generated neural activity by dendritically released opioids. Proceedings of the 2nd Annual Canadian Neuroscience Meeting. Retrieved from http://www.can-acn.org/meeting2008/index.html
Iremonger, K. J., & Bains, J. S. (2008). Long term depression of glutamatergic transmission by dendritically released opioids. Proceedings of the Society for Neuroscience Annual Meeting. SfN. Retrieved from http://www.sfn.org/index.aspx?pagename=abstracts_ampublications
Iremonger, K. J., & Bains, J. S. (2006). Asynchronous glutamate release prolongs postsynaptic excitation in central neurons. Proceedings of the Society for Neuroscience Annual Meeting. SfN. Retrieved from http://www.sfn.org/index.aspx?pagename=abstracts_ampublications
Conference Contribution - Poster Presentation (not in published proceedings)
Iremonger, K. J., & Herbison, A. E. (2010, November-December). Back-propagating action potentials evoke faithful calcium transients in the dendrites of GnRH neurons. Poster session presented at the Medical Sciences Congress: A New Decade of Discovery (MedSciNZ), Queenstown, New Zealand.
Conference Contribution - Verbal presentation and other Conference outputs
Iremonger, K. (2015, June). Long lasting calcium elevations in nerve terminals driven by brief neuropeptide signals. Verbal presentation at the 9th Annual Brain Health Research Centre Conference: Science for a Healthy Brain, Dunedin, New Zealand.
Jamieson, B. B., & Iremonger, K. J. (2015, August-September). Modulation of GABAergic synaptic input to CRH neurons by oxytocin. Verbal presentation at the Medical Sciences Congress (MedSci), Queenstown, New Zealand.
