Regulation of nociception threshold by norepinephrine through adrenergic α2 receptor in rat models of Parkinson's disease

© 2023 The Authors. CNS Neuroscience & Therapeutics published by John Wiley & Sons Ltd..

BACKGROUND: The mechanism of pain symptoms in Parkinson's disease (PD) is unclear. Norepinephrine (NE) regulates neuropathic pain through ascending and descending pathways. However, the loss of NE neurons in the brain of patients with PD is obvious, it is speculated that NE is involved in the occurrence of PD pain symptoms.

AIMS: To investigate the effect of NE on the activation of brain cells through adrenergic α2 receptor, so as to regulate the nociception threshold in a 6-OHDA-induced animal model of PD.

METHODS: PD rat model was established by 6-OHDA injection (6-OHDA group). DSP-4 (or anti-DBH-saporin) was used to reduce the NE level of the PD rat brain. The heat sensitivity threshold (HST) and pressure withdrawal threshold (PWT) were measured. Tyrosine hydroxylase and NE in rat brains were detected by Elisa. The percentage of GFAP-positive cells in the prefrontal cortex, cingulate gyrus and striatum of rats was detected by immunohistochemistry and immunofluorescence. GFAP protein was semiquantified by method of western blot. Then yohimbine and guanfacine were used to increase the NE level in PD rats, and the above experimental changes were observed after drug application.

RESULTS: The contents of NE in the brain of 6-OHDA-induced PD rats were lower than that of control group. After DSP-4 (or anti-DBH-saporin) injection, PD rats showed the lowest NE level (compared with 6-OHDA group, p ≤ 0.05), and after yohimbine and guanfacine were applied to 6-OHDA group, the contents of NE increased in the prefrontal cortex of rats. The HST and PWT of 6-OHDA group were significantly lower than those of control group, and after DSP-4 (or anti-DBH-saporin) injection, the HST and PWT of rats were lower than those of 6-OHDA group, and after the administration of yohimbine and guanfacine, both HST and PWT were significantly increased. GFAP-positive cells increased in prefrontal cortex and anterior cingulate gyrus of 6-OHDA group rats, and more significantly increased after DSP-4 (or anti-DBH-saporin) injection, and significantly reduced after yohimbine and guanfacine were used.

CONCLUSIONS: The change of norepinephrine content can affect the activation of prefrontal and cingulate gyrus glial cells and participate in the regulation of nociception threshold in PD rats. Adrenergic α2 receptor agonist and central presynaptic membrane α2 receptor blocker both affect cell activation and improve hyperalgesia.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:30

Enthalten in:

CNS neuroscience & therapeutics - 30(2024), 3 vom: 15. März, Seite e14446

Sprache:

Englisch

Beteiligte Personen:

Gao, Qing [VerfasserIn]
Zhang, Yingying [VerfasserIn]
Wang, Xiaoying [VerfasserIn]
Wang, Rui [VerfasserIn]
Zhang, Limei [VerfasserIn]

Links:

Volltext

Themen:

α2-adrenergic receptors
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30OMY4G3MK
8HW4YBZ748
Adrenergic alpha-2 Receptor Agonists
Benzylamines
DSP 4
EC 3.2.2.22
GFAP
Guanfacine
Journal Article
Nociception threshold
Norepinephrine
Oxidopamine
PQ1P7JP5C1
Parkinson's disease
Research Support, Non-U.S. Gov't
Saporins
X4W3ENH1CV
Yohimbine

Anmerkungen:

Date Completed 07.03.2024

Date Revised 18.04.2024

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1111/cns.14446

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM362182671