Serotonin-, substance P- and tyrosine hydroxylase-like immunoreactive neurons projecting from the periaqueductal gray to the ventromedial hypothalamic nucleus in the rat

Li, Yunqing; Zeng, Shui-Ling; Dong, Yuan-Xiang; Rao, Zhi-Ren; Shi, Ji-Wu

doi:10.1016/0304-3940(91)90502-k

Cited by 11 publications

(3 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…in the ventral hippocampus (Li et al, 1991a;Gradin et al, 1992) or serotonin content of the hypothalamus (Li et al, 1991b). Although some evidence suggests that NK1 receptor antagonists may modulate the activity of serotonergic neurons through a noradrenergic pathway (Haddjeri and Blier, 2000), the results of the present study suggest that NK1 receptor ligands could act through local circuits within the DRN to impact on serotonergic activity.…”

Section: Relationship Of Nk1 Receptor To Serotonergic Neuronsmentioning

confidence: 83%

Cellular basis for the effects of substance P in the periaqueductal gray and dorsal raphe nucleus

Commons

Valentino

2002

J of Comparative Neurology

View full text Add to dashboard Cite

Substance P (SP) is known to act at supraspinal sites to influence pain sensitivity as well as to promote anxiety. The effects of SP could be mediated in part by actions in the periaqueductal gray (PAG) and the dorsal raphe nucleus (DRN), adjoining mesencephalic cell groups that are strategically positioned to influence both nociception and mood. Previous studies have indicated that SP regulates both enkephalin and serotonin neurotransmission in these brain regions. To determine the mechanism underlying the effects of SP in the PAG and DRN, the distribution of the principal receptor for SP, the neurokinin 1 (NK1) receptor, was examined with respect to other neurotransmitter markers. PAG neurons that had NK1 receptor immunolabeling were interdigitated with and received contacts from enkephalin-containing neurons. However, only a few (16/144; 11%) neurons with NK1 receptor also contained enkephalin immunoreactivity after colchicine treatment. In the DRN, dendrites containing NK1 receptor were selectively distributed in the dorsomedial subdivision. The majority (132/137; 96%) of these dendrites did not contain immunoreactivity for the serotonin-synthesizing enzyme tryptophan hydroxylase. In contrast, neuronal profiles with NK1 receptor in both the PAG and the DRN often contained immunolabeling for glutamate. Light and electron microscopic examination revealed that 48-65% of cell bodies and dendrites with NK1 receptor were dually immunolabeled for glutamate. These data suggest that SP directly acts primarily on glutamatergic neurons in the PAG and DRN. To a lesser extent, enkephalin-containing neurons may be targeted. Through these actions, it may subsequently influence activity of larger populations of neurons containing enkephalin as well as serotonin. This circuitry could contribute to, as well as coordinate, effects of SP on pain perception and mood.

show abstract

Section: Relationship Of Nk1 Receptor To Serotonergic Neuronsmentioning

confidence: 83%

Cellular basis for the effects of substance P in the periaqueductal gray and dorsal raphe nucleus

Commons

Valentino

2002

J of Comparative Neurology

View full text Add to dashboard Cite

show abstract

“…Finally, the production of VADs relies on rhinencephalic-diencephalic structures (i.e., amygdala, septal area, midline thalamus, hypothalamus) that project to nucleus ambiguus and nucleus retroambiguus via the dorsolateral PAG (Holstege, 1989; Jürgens & Pratt, 1979; see review by Sutton & Jürgens, 1988). The vPAG and to a lesser extent the ventral medulla project to these rhinencephalic-diencephalic areas (vPAG : Li, Zeng, Dong, Rao, & Shi, 1991; Li, Jia, Rao, & Shi, 1990; Ma, Yin, Ai, & Han, 1991; Mantyh, 1983; Rizvi, Ennis, Behbehani, & Shipley, 1991; nRM : Bobillier et al, 1976; Takagi et al, 1981; nRGC : Peschanski & Besson, 1984; Vertes et al, 1986). Increases in VAD thresholds may therefore reflect combined inhibition at spinal, medullary, and rhinencephalic-diencephalic levels.…”

Section: Discussionmentioning

confidence: 99%

Increases in vocalization and motor reflex thresholds are influenced by the site of morphine microinjection: Comparisons following administration into the periaqueductal gray, ventral medulla, and spinal subarachnoid space.

Borszcz¹

1995

Behavioral Neuroscience

View full text Add to dashboard Cite

The relative influence of morphine microinjected into the periaqueductal gray, ventral medulla (nucleus raphé magnus or nucleus reticularis gigantocellularis), or spinal subarachnoid space on the thresholds of responses organized at spinal (spinal motor reflexes, SMRs), medullary (vocalizations elicited during shock, VDSs), and rhinencephalic-diencephalic (vocalization after discharges, VADs) levels of the neuraxis was assessed. Dose-dependent increases in response thresholds differed with the site of morphine injection. These results indicate that the mu-opiate-receptor-linked systems in the mesencephalon, medulla, and spinal cord exert differential antinociceptive effects on pain behaviors organized at different levels of the neuraxis. A hypothesis is offered regarding the mechanisms through which morphine inhibits nociceptive transmission through various levels of the CNS. VADs are promoted as a model system for analyzing the affective-motivational dimension of the pain experience.

show abstract

“…NK-1 binding sites and receptor messenger RNAs are found throughout the PAG (Dam, Martinelli, & Quirion, 1990; Maeno, Kiyama, & Tohyama, 1993; Quirion et al, 1983), whereas Substance P neurons and terminal fields are clustered in discrete populations that change over the various rostrocaudal levels of the PAG (Moss & Basbaum, 1983). Moreover, serotonin and Substance P containing neurons in the PAG have been shown to project to brain structures involved in fear behaviors, pain modulation, and autonomic regulation, such as the central nucleus of the amygdala, the ventromedial hypothalamus, and the nucleus tractus solitarii (Li, Jia, Rao, & Shi, 1990; Li, Zeng, Dong, Rao, & Shi, 1991; Li, Zeng, Rao, & Shi, 1992). Evidence also indicates a neuronal input from the lateral habenula contributing to Substance P terminal fields in the DR (Neckers, Schwartz, Wyatt, & Speciale, 1979; Vincent, Staines, McGeer, & Fibiger, 1980) and interactions between serotonin and Substance P in the DR and the ventral PAG (Liu & Swenberg, 1988; Magoul, Onteniente, Oblin, & Calas, 1986).…”

mentioning

confidence: 99%

Differential effects of neurokinin-1 receptor activation in subregions of the periaqueductal gray matter on conditional and unconditional fear behaviors in rats.

Mongeau¹,

De²,

Fanselow³

et al. 1998

Behavioral Neuroscience

View full text Add to dashboard Cite

Central neurokinin-1 (NK-1) receptors are thought to modulate aversion, whereas the periaqueductal gray matter (PAG) is a common pathway for the integration of fear behaviors. The authors determined whether injection of an NK-1 agonist (GR73632) into subregions of the PAG would alter fear-related behaviors. Behavioral inactivity was increased by GR73632 injected into the caudodorsal PAG or the dorsal raphe. Flight behavior induced by stimulation of the dorsal PAG or by a footshock was decreased after injection of GR73632 into the dorsal PAG. Rats that had 6 pairings of a tone with a footshock after injection of GR73632 into the dorsal PAG displayed more freezing behavior than controls at the beginning of the session. However, there was no change in the shock- or the tone-induced freezing because some GR73632-treated rats, but no controls, froze during the baseline period. It is concluded that NK-1 receptors in the dorsal PAG modulate the unconditional but not the mnemonic aspects of fear behaviors.

show abstract

Serotonin-, substance P- and tyrosine hydroxylase-like immunoreactive neurons projecting from the periaqueductal gray to the ventromedial hypothalamic nucleus in the rat

Cited by 11 publications

References 14 publications

Cellular basis for the effects of substance P in the periaqueductal gray and dorsal raphe nucleus

Cellular basis for the effects of substance P in the periaqueductal gray and dorsal raphe nucleus

Increases in vocalization and motor reflex thresholds are influenced by the site of morphine microinjection: Comparisons following administration into the periaqueductal gray, ventral medulla, and spinal subarachnoid space.

Differential effects of neurokinin-1 receptor activation in subregions of the periaqueductal gray matter on conditional and unconditional fear behaviors in rats.

Contact Info

Product

Resources

About