| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
NEUROHUMORAL CONTROL OF CARDIOVASCULAR FUNCTION
2Department of Pharmacology and Toxicology and 1Program in Medical Neurobiology, Indiana University School of Medicine, Indianapolis, Indiana 46202
Submitted 18 November 2003 ; accepted in final form 2 April 2004
Disinhibition of neurons in the region of the dorsomedial hypothalamus (DMH) elicits sympathetically mediated tachycardia in rats through activation of the brain stem raphe pallidus (RP), and this same mechanism appears to be largely responsible for the increases in heart rate (HR) seen in air jet stress in this species. Neurons projecting to the RP from the DMH are said to be concentrated in a specific subregion, the dorsal hypothalamic area (DA). Here, we examined the hypothesis that the location of RP-projecting neurons in the DA correspond to the sites at which microinjection of bicuculline methiodide (BMI) evokes the greatest increases in HR. To determine the distribution of RP-projecting neurons in the DA, cholera toxin B was injected in the RP in four rats. A consistent pattern of retrograde labeling was seen in every rat. In the hypothalamus, RP-projecting neurons were most heavily concentrated midway between the mammillothalamic tract and the dorsal tip of the third ventricle dorsal to the dorsomedial hypothalamic nucleus 
3.30 mm caudal to bregma. In a second series of experiments, the HR response to microinjections of BMI (2 pmol/5 nl; n = 76) was mapped at sites in the DA and surrounding areas in 22 urethane-anesthetized rats. All injection sites were located from 2.56 to 4.16 mm posterior to bregma, and the microinjections that evoked the largest increase in HR (i.e., >100 beats/min in some instances) were located in a region where RP-projecting neurons were most densely concentrated. Thus RP-projecting neurons in the DA may mediate DMH-induced tachycardia and thus play a role in stress-induced cardiac stimulation.
dorsomedial hypothalamus; sympathetic nervous system; dorsal hypothalamic area
This article has been cited by other articles:
|
|
 |
|
  J. Horiuchi, L. M. McDowall, and R. A. L. Dampney Vasomotor and respiratory responses evoked from the dorsolateral periaqueductal grey are mediated by the dorsomedial hypothalamus J. Physiol., November 1, 2009; 587(21): 5149 - 5162. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. C. A. de Menezes, D. V. Zaretsky, S. Sarkar, M. A. P. Fontes, and J. A. DiMicco Microinjection of muscimol into the periaqueductal gray suppresses cardiovascular and neuroendocrine response to air jet stress in conscious rats Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2008; 295(3): R881 - R890. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Sajdyk, P. Johnson, S. Fitz, and A. Shekhar Chronic inhibition of GABA synthesis in the bed nucleus of the stria terminalis elicits anxiety-like behavior J Psychopharmacol, August 1, 2008; 22(6): 633 - 641. [Abstract] [PDF]
|
|
|
|
|
|
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]
|
|
|
|
|
|
J. A. Rathner, C. J. Madden, and S. F. Morrison Central pathway for spontaneous and prostaglandin E2-evoked cutaneous vasoconstriction Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2008; 295(1): R343 - R354. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Tanaka and R. M. McAllen Functional topography of the dorsomedial hypothalamus Am J Physiol Regulatory Integrative Comp Physiol, February 1, 2008; 294(2): R477 - R486. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. A. DiMicco and D. V. Zaretsky The dorsomedial hypothalamus: a new player in thermoregulation Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2007; 292(1): R47 - R63. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Nakamura and S. F. Morrison Central efferent pathways mediating skin cooling-evoked sympathetic thermogenesis in brown adipose tissue Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2007; 292(1): R127 - R136. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Shekhar, P. L. Johnson, T. J. Sajdyk, S. D. Fitz, S. R. Keim, P. E. Kelley, D. R. Gehlert, and J. A. DiMicco Angiotensin-II Is a Putative Neurotransmitter in Lactate-Induced Panic-Like Responses in Rats with Disruption of GABAergic Inhibition in the Dorsomedial Hypothalamus J. Neurosci., September 6, 2006; 26(36): 9205 - 9215. [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]
|
|
|
|
|
|
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]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
