CNS cell groups projecting to sympathetic outflow of tail artery: neural circuits involved in heat loss in the rat

Smith, Julia E.; Jansen, A.S.P.; Gilbey, Michael P.; Loewy, A.

doi:10.1016/s0006-8993(97)01437-6

Cited by 221 publications

(166 citation statements)

References 39 publications

Supporting

Mentioning

159

Contrasting

Unclassified

Order By: Relevance

“…There are direct projections from these sites to the spinal cord, and projection targets include the intermediolateral column (6,15). In rats, transneuronal tracing studies demonstrate that medullary raphé and parapyramidal neurons, including 5-HT cells in the region, are labeled prominently and early after injection of pseudorabies virus into the tail (32,44), and our preliminary data using injection of pseudorabies virus into the ear pinna give similar results in rabbits (10). …”

Section: Discussionsupporting

confidence: 61%

“…Activity of these neurons contributes to the heat exchange aspect of thermoregulation as well as to the integrated bodily response to nociceptive or salient environmental events (7,21,35,36,39,42,45,49). Neuroanatomic studies using transneuronal transport of live virus injected into the tail vasculature indicate that a proportion of sympathetic premotor raphé-spinal neurons synthesize serotonin (5-hydroxytryptamine, 5-HT) (32,44).…”

Section: -11 M/s) Applications Of the 5-hydroxytryptamine (Ht)2a Anmentioning

confidence: 99%

See 1 more Smart Citation

Activation of slowly conducting medullary raphé-spinal neurons, including serotonergic neurons, increases cutaneous sympathetic vasomotor discharge in rabbit

Ootsuka¹,

Blessing²

2005

American Journal of Physiology-Regulatory, Integrative and Comp

View full text Add to dashboard Cite

Ootsuka, Youichirou, and William W. Blessing. Activation of slowly conducting medullary raphé-spinal neurons, including serotonergic neurons, increases cutaneous sympathetic vasomotor discharge in rabbit. Am J Physiol Regul Integr Comp Physiol 288: R909 -R918, 2005. First published November 18, 2004; doi:10.1152/ajpregu.00564. 2004.-Neurons in the rostral medullary raphé/parapyramidal region regulate cutaneous sympathetic nerve discharge. Using focal electrical stimulation at different dorsoventral raphé/parapyramidal sites in anesthetized rabbits, we have now demonstrated that increases in ear pinna cutaneous sympathetic nerve discharge can be elicited only from sites within 1 mm of the ventral surface of the medulla. By comparing the latency to sympathetic discharge following stimulation at the ventral raphé site with the corresponding latency following stimulation of the spinal cord [third thoracic (T3) dorsolateral funiculus] we determined that the axonal conduction velocity of raphé-spinal neurons exciting ear pinna sympathetic vasomotor nerves is 0.8 Ϯ 0.1 m/s (n ϭ 6, range 0.6 -1.1 m/s). Applications of the 5-hydroxytryptamine (, 80 g/kg in 0.8 ml) to the cerebrospinal fluid above thoracic spinal cord (T1-T7), but not the lumbar spinal cord (L2-L4), reduced raphé-evoked increases in ear pinna sympathetic vasomotor discharge from 43 Ϯ 9 to 16 Ϯ 6% (P Ͻ 0.01, n ϭ 8). Subsequent application of the excitatory amino acid (EAA) antagonist kynurenic acid (25 mol in 0.5 ml) substantially reduced the remaining evoked discharge (22 Ϯ 8 to 6 Ϯ 6%, P Ͻ 0.05, n ϭ 5). Our conduction velocity data demonstrate that only slowly conducting raphé-spinal axons, in the unmyelinated range, contribute to sympathetic cutaneous vasomotor discharge evoked by electrical stimulation of the medullary raphé/parapyramidal region. Our pharmacological data provide evidence that raphé-spinal neurons using 5-HT as a neurotransmitter contribute to excitation of sympathetic preganglionic neurons regulating cutaneous vasomotor discharge. Raphé-spinal neurons using an EAA, perhaps glutamate, make a substantial contribution to the ear sympathetic nerve discharge evoked by raphé stimulation.5-hydroxytryptamine2A receptors; kynurenic acid; SR-46349B; sympathetic preganglionic neuron; cutaneous blood flow NEURONS IN THE ROSTRAL MEDULLARY raphé/parapyramidal region regulate cutaneous vasomotor tone by controlling cutaneous sympathetic preganglionic neuronal activity (7,39,42,45). Identification and characterization of the relevant neurons is an important task. Activity of these neurons contributes to the heat exchange aspect of thermoregulation as well as to the integrated bodily response to nociceptive or salient environmental events (7,21,35,36,39,42,45,49). Neuroanatomic studies using transneuronal transport of live virus injected into the tail vasculature indicate that a proportion of sympathetic premotor raphé-spinal neurons synthesize serotonin (5-hydroxytryptamine, 5-HT) (32, 44).Although 5-HT is a neurotransmitter traditionally considered...

show abstract

Section: Discussionsupporting

confidence: 61%

Section: -11 M/s) Applications Of the 5-hydroxytryptamine (Ht)2a Anmentioning

confidence: 99%

Activation of slowly conducting medullary raphé-spinal neurons, including serotonergic neurons, increases cutaneous sympathetic vasomotor discharge in rabbit

Ootsuka¹,

Blessing²

2005

American Journal of Physiology-Regulatory, Integrative and Comp

View full text Add to dashboard Cite

show abstract

“…Recent findings on the efferent control of sympathetic CVC tone indicate that the effector signaling from the POA leading to temperature-dependent CVC control is mediated by the rostral medullary raphe including the rostral raphe pallidus (30), a site of sympathetic premotor neurons controlling skin blood vessels (31,32). The absence of evidence for brain sites intermediate between the POA and the rostral medullary raphe that are required for the POA efferent signaling for temperature-dependent CVC control supports the significance of the direct projection from POA neurons to the rostral medullary raphe as the efferent pathway for febrile and thermoregulatory control of cutaneous vasoconstriction (30,33,34).…”

Section: Discussionmentioning

confidence: 99%

A thermosensory pathway mediating heat-defense responses

Nakamura

Morrison

2010

Proc. Natl. Acad. Sci. U.S.A.

225

239

View full text Add to dashboard Cite

Afferent neural transmission of temperature sensation from skin thermoreceptors to the central thermoregulatory system is important for the defense of body temperature against environmental thermal challenges. Here, we report a thermosensory pathway that triggers physiological heat-defense responses to elevated environmental temperature. Using in vivo electrophysiological and anatomical approaches in the rat, we found that neurons in the dorsal part of the lateral parabrachial nucleus (LPBd) glutamatergically transmit cutaneous warm signals from spinal somatosensory neurons directly to the thermoregulatory command center, the preoptic area (POA). Intriguingly, these LPBd neurons are located adjacent to another group of neurons that mediate cutaneous cool signaling to the POA. Functional experiments revealed that this LPBd–POA warm sensory pathway is required to elicit autonomic heat-defense responses, such as cutaneous vasodilation, to skin-warming challenges. These findings provide a fundamental framework for understanding the neural circuitry maintaining thermal homeostasis, which is critical to survive severe environmental temperatures.

show abstract

“…7A that receives projections from other Fospositive areas including the preoptic region (Murphy et al, 1999), the bed nucleus of the stria terminalis, the central nucleus of the amygdala, the dorsal and lateral hypothalamic areas, the ventrolateral periaqueductal gray, the parabrachial nuclei, and the subcoeruleus area (Hermann, et al, 1997;Mason, 2001). This restricted area also projects to the preoptic area (Murphy, et al, 1999) and is the source of multisynaptic sympathetic pathways to brown fat and to blood vessels in the tail that induce fever (Smith et al, 1998). CLP induced Fos in serotonergic cells.…”

Section: Discussionmentioning

confidence: 99%

Central neural distribution of immunoreactive Fos and CRH in relation to plasma ACTH and corticosterone during sepsis in the rat

Carlson

Chiu

Fiedler

et al. 2007

Experimental Neurology

View full text Add to dashboard Cite

Although brain pathways activated by sepsis may respond acutely to endotoxin administration, the long-term central response to sepsis is not known. We prepared male rats for hormonal sampling at the circadian nadir (AM) and peak (PM) after cecal ligation and puncture (CLP) or sham surgery. Diurnal variation of corticosterone was present on postoperative day (D) 3 and D4 after sham surgery but not after CLP. CLP increased Fos immunostaining in the nucleus of tractus solitarius (NTS), ventrolateral medulla, medullary raphe, parabrachial nucleus, hypothalamus, amygdala, bed nucleus of stria terminalis, and preoptic region. Fos responses were generally greatest on D1 but persisted to the AM of D4. The number of Fos-positive cell nuclei in the NTS on D3 and D4 did not differ but had greater variance on D3 than on D4 (P < 0.01) with a divergent response in the PM of D3 that was correlated with plasma ACTH (r = 0.927, P<0.01) but not with corticosterone. CLP increased CRH-staining intensity in the hypothalamic paraventricular neurons uniformly from D1 through D4 (P<0.01). Similar to Fos in NTS, this response was correlated with plasma ACTH (r = 0.738, P<0.05) and adrenal size (r = 0.730, P<0.05) in the PM of D3. Neuronal CRH became detectable after CLP in specific medullary areas on D1 and in the preoptic region on D3 and D4. Thus, the suppression of circadian variation by CLP was associated with central neural responses that increased in relation to plasma ACTH without apparent influence on the release of corticosterone.

show abstract

CNS cell groups projecting to sympathetic outflow of tail artery: neural circuits involved in heat loss in the rat

Cited by 221 publications

References 39 publications

Activation of slowly conducting medullary raphé-spinal neurons, including serotonergic neurons, increases cutaneous sympathetic vasomotor discharge in rabbit

Activation of slowly conducting medullary raphé-spinal neurons, including serotonergic neurons, increases cutaneous sympathetic vasomotor discharge in rabbit

A thermosensory pathway mediating heat-defense responses

Central neural distribution of immunoreactive Fos and CRH in relation to plasma ACTH and corticosterone during sepsis in the rat

Contact Info

Product

Resources

About