|
|
||||||||
Department of Physiology and Institute for Biomedical Research, University of Sydney, New South Wales 2006, Australia
Physiological and anatomic methods were used to determine whether neurons in the rostral ventrolateral medulla (RVLM), nucleus tractus solitarius (NTS), or hypothalamic paraventricular nucleus (PVN) mediate the cardiovascular response evoked from the dorsomedial hypothalamic nucleus (DMH), which is believed to play a key role in mediating responses to stress. In urethane-anesthetized rats, activation of neurons in the DMH by microinjection of bicuculline resulted in a large increase in arterial pressure, heart rate, and renal sympathetic nerve activity. The pressor and sympathoexcitatory responses, but not the tachycardic response, were greatly reduced after bilateral muscimol injections into the RVLM even when baseline arterial pressure was maintained at a constant level. These responses were not reduced by muscimol injections into the PVN or NTS. Retrograde tracing experiments identified many neurons in the DMH that projected directly to the RVLM. The results indicate that the vasomotor and cardiac components of the response evoked from the DMH are mediated by pathways that are dependent and independent, respectively, of neurons in the RVLM.
rostral ventrolateral medulla; nucleus tractus solitarius; paraventricular nucleus; stress
This article has been cited by other articles:
![]() |
P. Johnson, C. Lowry, W. Truitt, and A. Shekhar Disruption of GABAergic tone in the dorsomedial hypothalamus attenuates responses in a subset of serotonergic neurons in the dorsal raphe nucleus following lactate-induced panic J Psychopharmacol, August 1, 2008; 22(6): 642 - 652. [Abstract] [PDF] |
||||
![]() |
L. M. McDowall, J. Horiuchi, and R. A. L. Dampney Effects of disinhibition of neurons in the dorsomedial hypothalamus on central respiratory drive Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2007; 293(4): R1728 - R1735. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. D. Womack and R. Barrett-Jolley Autonomic Neuroscience: Activation of paraventricular nucleus neurones by the dorsomedial hypothalamus via a tachykinin pathway in rats Exp Physiol, July 1, 2007; 92(4): 671 - 676. [Abstract] [Full Text] [PDF] |
||||
![]() |
D.-P. Li and H.-L. Pan Glutamatergic Inputs in the Hypothalamic Paraventricular Nucleus Maintain Sympathetic Vasomotor Tone in Hypertension Hypertension, April 1, 2007; 49(4): 916 - 925. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. L. Johnson and A. Shekhar Panic-prone state induced in rats with GABA dysfunction in the dorsomedial hypothalamus is mediated by NMDA receptors. J. Neurosci., June 28, 2006; 26(26): 7093 - 7104. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. M. McDowall, J. Horiuchi, S. Killinger, and R. A. L. Dampney Modulation of the baroreceptor reflex by the dorsomedial hypothalamic nucleus and perifornical area Am J Physiol Regulatory Integrative Comp Physiol, April 1, 2006; 290(4): R1020 - R1026. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. De Matteo, G. A. Head, and D. N. Mayorov Angiotensin II in dorsomedial hypothalamus modulates cardiovascular arousal caused by stress but not feeding in rabbits Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2006; 290(1): R257 - R264. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. W. Blessing BAT control shows the way: medullary raphe/parapyramidal neurons and sympathetic regulation of brown adipose tissue Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2005; 288(3): R557 - R560. [Full Text] [PDF] |
||||
![]() |
W.-H. Cao and S. F. Morrison Brown adipose tissue thermogenesis contributes to fentanyl-evoked hyperthermia Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2005; 288(3): R723 - R732. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Horiuchi, R. M. McAllen, A. M. Allen, S. Killinger, M. A. P. Fontes, and R. A. L. Dampney Descending vasomotor pathways from the dorsomedial hypothalamic nucleus: role of medullary raphe and RVLM Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2004; 287(4): R824 - R832. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. C. Samuels, D. V. Zaretsky, and J. A. DiMicco Dorsomedial hypothalamic sites where disinhibition evokes tachycardia correlate with location of raphe-projecting neurons Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2004; 287(2): R472 - R478. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. F. Hayward, M. Castellanos, and P. W. Davenport Parabrachial neurons mediate dorsal periaqueductal gray evoked respiratory responses in the rat J Appl Physiol, March 1, 2004; 96(3): 1146 - 1154. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. B. Evans, C. W. Wilkinson, P. Gronbeck, J. L. Bennett, A. Zavosh, G. J. Taborsky Jr, and D. P. Figlewicz Inactivation of the DMH selectively inhibits the ACTH and corticosterone responses to hypoglycemia Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2004; 286(1): R123 - R128. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. Sevoz-Couche, M.-A. Comet, M. Hamon, and R. Laguzzi Role of Nucleus Tractus Solitarius 5-HT3 Receptors in the Defense Reaction-Induced Inhibition of the Aortic Baroreflex in Rats J Neurophysiol, October 1, 2003; 90(4): 2521 - 2530. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |