Role of the median preoptic nucleus in the autonomic response to heat-exposure

Abbott, Stephen B.G.; Saper, Clifford B.

doi:10.1080/23328940.2017.1413155

“…Activation of leptin receptor expressing VMPO neurons also causes mice to display similar postural extension behavior as we observed following activation of Dyn PBN→POA terminals (Figure 7) (Yu et al, 2016). Furthermore, glutamatergic neurons in MnPO, which can drive vasodilation, are potential likely targets of the PBN warmactivated cells (Abbott and Saper, 2018). Expression of KOR or MOR in these POA neuronal populations has not been delineated, but injections of opioid receptor agonists into the POA has been shown to alter body temperature indicating that opioid receptors, either pre or post synaptic to the PBN terminals, may have important functional neuromodulatory roles in thermoregulation (Xin et al, 1997).…”

Section: Overlapping Populations Of Warm-activated Pbn Neurons Expressupporting

confidence: 57%

Parabrachial Opioidergic Projections to Preoptic Hypothalamus Mediate Behavioral and Physiological Thermal Defenses

Norris

¹

,

Shaker

²

,

Cone

³

et al. 2020

Preprint

View full text Add to dashboard Cite

Maintaining stable body temperature through environmental thermal stressors requires detection of temperature changes, relay of information, and coordination of physiological and behavioral responses. Studies have implicated areas in the preoptic hypothalamic area (POA) and the parabrachial nucleus (PBN) as nodes in the thermosensory neural circuitry and indicate the opioid system within the POA is vital in regulating body temperate. In the present study we identify neurons projecting to the POA from PBN expressing the opioid peptides Dynorphin (Dyn) and Enkephalin (Enk). We determine that warm-activated PBN neuronal populations overlap with both Dyn and Enk expressing PBN populations. We demonstrate that Dyn and Enk expressing neurons are partially overlapping subsets of a glutamatergic population in the PBN. Using optogenetic approaches we selectively activate projections in the POA from PBN Dyn, Enk, and VGLUT2 expressing neurons. Our findings demonstrate that Dyn, Enk, and VGLUT2 expressing PBN neurons are critical for physiological and behavioral heat defense. potential roles of opioid receptor mediated behaviors in both Dyn+ and Enk+ PBN-POA projections. Here we report that glutamatergic, Dyn+, and Enk+ neuronal populations projecting from PBN to POA initiate physiological and behavioral heat defensive behaviors. Chemogenetic inhibition of glutamatergic PBN neurons blocks vasomotor responses to thermal heat challenge.The studies reported here provide new insights into the thermoregulatory properties of parabrachial neuropeptide-containing projections to the hypothalamus in homeostatic and metabolic behavior. Results Ambient warmth activates Dyn+ and Enk+ neurons in PBNEffects of mu and kappa receptor signaling on body temperature have been described and mRNA for preprodynorphin and preproenkephalin has been reported to be expressed in the PBN (Baker and Meert, 2002;Chen et al., 2005;Clark, 1979;Engstrom et al., 2001;Hermanson and Blomqvist, 1997;Hermanson et al., 1998). To examine if PBN neurons expressing dynophin or enkephalin opioid neuropeptides are activated by ambient warmth, we exposed mice to ambient warmth (38°C) or room temperature (21-23°C) for four hours prior to preparation of brain for fos staining. We performed immunohistochemistry (IHC) on collected brains sections containing the PBN with antibody directed against c-Fos (anti-c-Fos) to examine induction of c-Fos expression as a marker of neuronal activation (Sheng and Greenberg, 1990). Consistent with recent reports, we observed induction of c-Fos expression in the lateral PBN (LPBN) (Figure 1B-C) (Geerling et al., 2016). In brain sections from warm exposed mice (n=8) compared to room temperature controls (n=4), c-Fos staining revealed a robust and significant (p=0.003) increase in mean ±SEM number of neurons positive for c-Fos expression in the LPBN per brain: 265.8 ±41.9 in warm exposed mice compared to 23.2 ±4.0 in room temperature controls (Figure 1C).Cells in LPBN, lateral to superior cerebellar peduncle, in sections corresponding -5.0 ...

show abstract

“…Further, activation of leptin receptor expressing VMPO neurons also causes mice to display similar postural extension behavior as we observed following activation of Pdyn PBN→POA terminals ( Figure 7 ; Yu et al, 2016 ). Glutamatergic neurons in MnPO can drive vasodilation and may also be targets of the PBN warm-activated cells ( Abbott and Saper, 2018 ).…”

Section: Discussionmentioning

confidence: 99%

“…The POA contains neurons critical for integration of information about body temperature and for coordination of responses to thermal challenges to maintain core temperature ( Abbott and Saper, 2017 ; Abbott and Saper, 2018 ; Tan et al, 2016 ). Neurons in POA, identified by different genetic markers, can regulate BAT activation, drive vasodilation, and shift ambient temperature preferences ( Tan et al, 2016 ; Yu et al, 2016 ).…”

Section: Introductionmentioning

confidence: 99%

Parabrachial opioidergic projections to preoptic hypothalamus mediate behavioral and physiological thermal defenses

Norris

¹

,

Shaker

²

,

Cone

³

et al. 2021

eLife

View full text Add to dashboard Cite

Maintaining stable body temperature through environmental thermal stressors requires detection of temperature changes, relay of information, and coordination of physiological and behavioral responses. Studies have implicated areas in the preoptic area of the hypothalamus (POA) and the parabrachial nucleus (PBN) as nodes in the thermosensory neural circuitry and indicate that the opioid system within the POA is vital in regulating body temperature. In the present study we identify neurons projecting to the POA from PBN expressing the opioid peptides dynorphin and enkephalin. Using mouse models, we determine that warm-activated PBN neuronal populations overlap with both prodynorphin (Pdyn) and proenkephalin (Penk) expressing PBN populations. Here we report that in the PBN Prodynorphin (Pdyn) and Proenkephalin (Penk) mRNA expressing neurons are partially overlapping subsets of a glutamatergic population expressing Solute carrier family 17 (Slc17a6) (VGLUT2). Using optogenetic approaches we selectively activate projections in the POA from PBN Pdyn, Penk, and VGLUT2 expressing neurons. Our findings demonstrate that Pdyn, Penk, and VGLUT2 expressing PBN neurons are critical for physiological and behavioral heat defense.

show abstract

“…Such non-photic signals include exercise, feeding, and temperature (McArthur et al, 1991 ; Damiola et al, 2000 ; Buxton et al, 2003 ; Escobar et al, 2009 ; Buhr et al, 2010 ). Previous findings showed that a majority of the preoptic neurons were activated by heat exposure and were located in the VMPO (Tan et al, 2016 ; Abbott and Saper, 2018 ). Our results revealed that the VMPO region had a robust projection to SCN CCK neurons; the interconnection between the two areas supports the idea of circadian entrainment by temperature.…”

Section: Discussionmentioning

confidence: 94%

Whole-Brain Monosynaptic Afferent Projections to the Cholecystokinin Neurons of the Suprachiasmatic Nucleus

Yuan

¹

,

Wei

²

,

Xu

³

et al. 2018

View full text Add to dashboard Cite

The suprachiasmatic nucleus (SCN) is the principal pacemaker driving the circadian rhythms of physiological behaviors. The SCN consists of distinct neurons expressing neuropeptides, including arginine vasopressin (AVP), vasoactive intestinal polypeptide (VIP), gastrin-releasing peptide (GRP), cholecystokinin (CCK), and so on. AVP, VIP, and GRP neurons receive light stimulation from the retina to synchronize endogenous circadian clocks with the solar day, whereas CCK neurons are not directly innervated by retinal ganglion cells and may be involved in the non-photic regulation of the circadian clock. To better understand the function of CCK neurons in non-photic circadian rhythm, it is vital to clarify the direct afferent inputs to CCK neurons in the SCN. Here, we utilized a recently developed rabies virus- and Cre/loxP-based, cell type-specific, retrograde tracing system to map and quantitatively analyze the whole-brain monosynaptic inputs to SCN CCK neurons. We found that SCN CCK neurons received direct inputs from 29 brain nuclei. Among these nuclei, paraventricular nucleus of the hypothalamus (PVH), paraventricular nucleus of the thalamus (PVT), supraoptic nucleus (SON), ventromedial nucleus of the hypothalamus, and seven other nuclei sent numerous inputs to CCK neurons. Moderate inputs originated from the zona incerta, periventricular hypothalamic nucleus, and five other nuclei. A few inputs to CCK neurons originated from the orbital frontal cortex, prelimbic cortex, cingulate cortex, claustrum, and seven other nuclei. In addition, SCN CCK neurons were preferentially innervated by AVP neurons of the ipsilateral PVH and SON rather than their contralateral counterpart, whereas the contralateral PVT sent more projections to CCK neurons than to its ipsilateral counterpart. Taken together, these results expand our knowledge of the specific innervation to mouse SCN CCK neurons and provide an important indication for further investigations on the function of CCK neurons.

show abstract

Role of the median preoptic nucleus in the autonomic response to heat-exposure

Cited by 12 publications

References 5 publications

Parabrachial Opioidergic Projections to Preoptic Hypothalamus Mediate Behavioral and Physiological Thermal Defenses

Parabrachial Opioidergic Projections to Preoptic Hypothalamus Mediate Behavioral and Physiological Thermal Defenses

Parabrachial opioidergic projections to preoptic hypothalamus mediate behavioral and physiological thermal defenses

Whole-Brain Monosynaptic Afferent Projections to the Cholecystokinin Neurons of the Suprachiasmatic Nucleus

Contact Info

Product

Resources

About