Glenn M. Toney, Ph.D.

Contact

Department

Cellular and Integrative Physiology

Glenn M. Toney, Ph.D.

Ashbel Smith Professor

Education

B.S., Weber State College, 1988
Ph.D., University of Louisville, 1992

Research

Neurons in the PVN receive many different types of sensory input and can produce a variety of effects mediated through the sympathetic nervous system. Prominent among PVN neurons comprising sympathetic efferent pathways are those that form monosynaptic connections with the rostral ventrolateral medulla (rVLM) and the nucleus tractus solitarius (NTS) in the hindbrain and the intermediolateral cell column (IML) in the spinal cord. Connectivity and functional studies provide evidence that the PVN is a critically important site for central control of cardiovascular and body fluid regulatory functions.

Autonomic PVN neurons are recruited following specific changes in extracellular fluid volume and osmolarity. At present we do not know if volume and osmotic disturbances are mediated by separate (i.e., spatially distinct) PVN pathways or if common descending efferents are activated in response to both sensory inputs. How individual neurons in specific PVN pathways respond to volume and/or osmotic challenges is beginning to be revealed through in vivo electrophysiological approaches.  The underlying neurotransmitter mechanisms and intracellular signaling cascades that mediate these discharge responses are not fully understood, but L-glutamate and the neuropeptide angiotensin II are likely candidates.  Expansion of understanding of PVN control of specific efferent pathways using in vivo and brain slice electrophysiological techniques, optogenetics, viral transduction, neuroanatomical methods as well as integrative whole animal approaches .

Major goals for my lab are to provide new knowledge regarding the basic function of specific groups of autonomic neurons and to determine how these groups of neurons are involved in cardiovascular disease. We are currently interested in determining how the PVN contributes to autonomic disturbances that accompany angiotensin II- and sodium-sensitive models of hypertension as well as congestive heart failure. Studies currently underway are designed to provide new insights into the pathologic changes in neurotransmission that occur in these cardiovascular diseases. These efforts represent an important step toward the development of centrally acting drugs that effectively reduce sympathetic activity in patients with hypertension or heart failure without producing episodes of severe hypotension characteristic of current centrally acting sympatholytic treatments

Lab Members

 

 Mary Ann Andrade
Research Associate – Senior
Postdoctoral Fellow
Tamara Truong
Research Technician – Intermediate
Postdoctoral Fellow
Robert Hammack
 Ph.D. Candidate/Graduate Student

Publications

Oxytocin receptor activation rescues opioid-induced respiratory depression by systemic fentanyl in the rat.
Brackley AD, Toney GM.
J Pharmacol Exp Ther. 2021 May 14:JPET-AR-2021-000535. doi: 10.1124/jpet.121.000535. Online ahead of print.
PMID: 33990416

High dietary salt amplifies osmoresponsiveness in vasopressin-releasing neurons.
Levi DI, Wyrosdic JC, Hicks AI, Andrade MA, Toney GM, Prager-Khoutorsky M, Bourque CW.
Cell Rep. 2021 Mar 16;34(11):108866. doi: 10.1016/j.celrep.2021.108866.
PMID: 33730577 Free PMC article.

Intermittent hypercapnic hypoxia induces respiratory hypersensitivity to fentanyl accompanied by tonic respiratory depression by endogenous opioids.
Brackley AD, Andrade MA, Toney GM.
J Physiol. 2020 Aug;598(15):3239-3257. doi: 10.1113/JP280021. Epub 2020 Jun 14.
PMID: 32415789 Free PMC article.

Central AT1 receptor signaling by circulating angiotensin II is permissive to acute intermittent hypoxia-induced sympathetic neuroplasticity.
Shimoura CG, Andrade MA, Toney GM.
J Appl Physiol (1985). 2020 May 1;128(5):1329-1337. doi: 10.1152/japplphysiol.00094.2020. Epub 2020 Apr 2.
PMID: 32240022 Free PMC article.

Neuroinflammation Contributes to High Salt Intake-Augmented Neuronal Activation and Active Coping Responses to Acute Stress.
Gilman TL, Mitchell NC, Daws LC, Toney GM.
Int J Neuropsychopharmacol. 2019 Feb 1;22(2):137-142. doi: 10.1093/ijnp/pyy099.
PMID: 30535261 Free PMC article.

Activation of the hypothalamic paraventricular nucleus by acute intermittent hypoxia: Implications for sympathetic long-term facilitation neuroplasticity.
Maruyama NO, Mitchell NC, Truong TT, Toney GM.
Exp Neurol. 2019 Apr;314:1-8. doi: 10.1016/j.expneurol.2018.12.011. Epub 2018 Dec 31.
PMID: 30605624 Free PMC article.