Associate Professor Karl Iremonger

Contact Details
- Phone
- +64 3 479 7300
- karl.iremonger@otago.ac.nz
- Position
- Associate Professor
- Department
- Department of Physiology
- Qualifications
- PhD
- Research summary
- Neuroendocrinology
Research
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.
Publications
Power, E. M., Ganeshan, D., & Iremonger, K. J. (2023). Estradiol regulates voltage-gated potassium currents in corticotropin-releasing hormone neurons. Journal of Experimental Biology. Advance online publication. doi: 10.1242/jeb.245222
Ohline, S. M., Liu, X., Ibrahim, M. F., Mockett, B. G., Empson, R. M., Abraham, W. C., Iremonger, K. J., & Jones, P. P. (2022). Altered membrane properties but unchanged intrinsic excitability and spontaneous postsynaptic currents in an aged APPswe/PS1dE9 model of Alzheimer’s disease. Frontiers in Cellular Neuroscience, 16, 958876. doi: 10.3389/fncel.2022.958876
Gouws, J. M., Sherrington, A., Zheng, S., Kim, J. S., & Iremonger, K. J. (2022). Regulation of corticotropin-releasing hormone neuronal network activity by noradrenergic stress signals. Journal of Physiology, 600(19), 4347-4359. doi: 10.1113/JP283328
Abbasi, M., Augustine, R. A., Iremonger, K. J., & Brown, C. H. (2022). Central kisspeptin does not affect ERK1/2 or p38 phosphorylation in oxytocin neurons of late-pregnant rats. International Journal of Molecular Sciences, 23(14), 7729. doi: 10.3390/ijms23147729
Abbasi, M., Perkinson, M. R., Seymour, A. J., Piet, R., Campbell, R. E., Iremonger, K. J., & Brown, C. H. (2022). Local kisspeptin excitation of rat oxytocin neurones in late pregnancy. Journal of Physiology, 600(7), 1753-1770. doi: 10.1113/jp282531
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
Chapter in Book - Research
Power, E. M., Ganeshan, D., & Iremonger, K. J. (2023). Estradiol regulates voltage-gated potassium currents in corticotropin-releasing hormone neurons. Journal of Experimental Biology. Advance online publication. doi: 10.1242/jeb.245222
Journal - Research Article
Abbasi, M., Augustine, R. A., Iremonger, K. J., & Brown, C. H. (2022). Central kisspeptin does not affect ERK1/2 or p38 phosphorylation in oxytocin neurons of late-pregnant rats. International Journal of Molecular Sciences, 23(14), 7729. doi: 10.3390/ijms23147729
Journal - Research Article
Abbasi, M., Perkinson, M. R., Seymour, A. J., Piet, R., Campbell, R. E., Iremonger, K. J., & Brown, C. H. (2022). Local kisspeptin excitation of rat oxytocin neurones in late pregnancy. Journal of Physiology, 600(7), 1753-1770. doi: 10.1113/jp282531
Journal - Research Article
Gouws, J. M., Sherrington, A., Zheng, S., Kim, J. S., & Iremonger, K. J. (2022). Regulation of corticotropin-releasing hormone neuronal network activity by noradrenergic stress signals. Journal of Physiology, 600(19), 4347-4359. doi: 10.1113/JP283328
Journal - Research Article
Jamieson, B. B., Kim, J. S., & Iremonger, K. J. (2022). Cannabinoid and vanilloid pathways mediate opposing forms of synaptic plasticity in corticotropin-releasing hormone neurons. Journal of Neuroendocrinology, 34, e13084. doi: 10.1111/jne.13084
Journal - Research Article
Ohline, S. M., Liu, X., Ibrahim, M. F., Mockett, B. G., Empson, R. M., Abraham, W. C., Iremonger, K. J., & Jones, P. P. (2022). Altered membrane properties but unchanged intrinsic excitability and spontaneous postsynaptic currents in an aged APPswe/PS1dE9 model of Alzheimer’s disease. Frontiers in Cellular Neuroscience, 16, 958876. doi: 10.3389/fncel.2022.958876
Journal - Research Article
Nair, B. B., Khant Aung, Z., Porteous, R., Prescott, M., Glendining, K. A., Jenkins, D. E., Augustine, R. A., Silva, M. S. B., Yip, S. H., Bouwer, G. T., Brown, C. H., Jasoni, C. L., Campbell, R. E., Bunn, S. J., Anderson, G. M., Grattan, D. R., Herbison, A. E., & Iremonger, K. J. (2021). Impact of chronic variable stress on neuroendocrine hypothalamus and pituitary in male and female C57BL/6J mice. Journal of Neuroendocrinology, 33, e12972. doi: 10.1111/jne.12972
Journal - Research Article
Power, E. M., & Iremonger, K. J. (2021). Plasticity of intrinsic excitability across the estrous cycle in hypothalamic CRH neurons. Scientific Reports, 11(1), 16700. doi: 10.1038/s41598-021-96341-4
Journal - Research Article
Focke, C. M. B., & Iremonger, K. J. (2020). Rhythmicity matters: Circadian and ultradian patterns of HPA axis activity. Molecular & Cellular Endocrinology, 501, 110652. doi: 10.1016/j.mce.2019.110652
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, 154, 79-86. doi: 10.1016/j.neuropharm.2019.02.017
Journal - Research Article
Kim, J. S., Han, S. Y., & Iremonger, K. J. (2019). Stress experience and hormone feedback tune distinct components of hypothalamic CRH neuron activity. Nature Communications, 10, 5696. doi: 10.1038/s41467-019-13639-8
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
Iremonger, K. J., & Herbison, A. E. (2015). Multitasking in gonadotropin-releasing hormone neuron dendrites. Neuroendocrinology, 102(1-2), 1-7. doi: 10.1159/000368364
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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
Journal - Research Article
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 Article
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
Journal - Research Article
Perkinson, M. R., Kim, J. S., Iremonger, K. J., & Brown, C. H. (2021). Visualising oxytocin neurone activity in vivo: The key to unlocking central regulation of parturition and lactation [Invited review]. Journal of Neuroendocrinology, 33, e13012. doi: 10.1111/jne.13012
Journal - Research Other
Kim, J. S., & Iremonger, K. J. (2019). Temporally tuned corticosteroid feedback regulation of the stress axis. Trends in Endocrinology & Metabolism, 30(11), 783-792. doi: 10.1016/j.tem.2019.07.005
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
Journal - Research Other