Background And Purpose: Little is known of how cranial autonomic symptoms (CAS) in cluster headache and migraine may contribute to their severe headache phenotype. This strong association suggests the involvement of the cranial parasympathetic efferent pathway. To investigate its contribution, we studied the role of pituitary adenylate cyclase activating polypeptide-38 (PACAP-38), a potent sensory and parasympathetic neuropeptide, in modulating pre- and post-ganglionic cranial parasympathetic projection neurons, and their influence on headache-related trigeminal-autonomic responses.

Experimental Approach: Using PACAP-38 and PACAP-38 responsive receptor antagonists, electrophysiological, behavioural and facial neurovascular-blood flow was measured in rats to probe trigeminal- and parasympathetic-neuronal, periorbital thresholds and cranial-autonomic outcomes, as they relate to primary headaches.

Key Results: Sumatriptan attenuated the development of PACAP-38 mediated activation and sensitization of trigeminocervical neurons and related periorbital allodynia. PACAP-38 also caused activation and enhanced responses of dural-responsive pre-ganglionic pontine-superior salivatory parasympathetic neurons. Further, the PACAP-38 responsive receptor antagonists dissected a role of VPAC and PAC receptors in attenuating cranial-autonomic and trigeminal-neuronal responses to activation of the cranial parasympathetic projection, which requires post-ganglionic parasympathetic neurotransmission.

Conclusion And Implications: Given the prevailing view that sumatriptan acts to some degree via a peripheral mechanism, our data support that PACAP-38 mediated receptor activation modulates headache-related cranial-autonomic and trigeminovascular responses via peripheral and central components of the cranial parasympathetic projection. This provides a mechanistic rationale for the association of CAS with more severe headache phenotypes in cluster headache and migraine, and supports the cranial parasympathetic projection as a potential novel locus for treatment by selectively targeting PACAP-38 or PACAP-38 responsive VPAC /PAC receptors.

Download full-text PDF

Source
http://dx.doi.org/10.1111/bph.16242DOI Listing

Publication Analysis

Top Keywords

cranial parasympathetic
24
parasympathetic projection
16
pacap-38 responsive
12
pacap-38
10
parasympathetic
9
cluster headache
8
headache migraine
8
severe headache
8
pacap-38 pacap-38
8
responsive receptor
8

Similar Publications

Third nerve palsies that result from head injuries or intracranial aneurysms may sometimes show symptoms of aberrant regeneration and only partially heal. The usual characteristics of oculomotor nerve palsy, caused by compression of the third cranial nerve, are severe ptosis, deficiencies in elevation, depression, and adduction, and a dilated, poorly responding pupil on the afflicted side. The parasympathetic fibres are usually spared from a vasculopathic lesion and impacted by compressive lesions because they are situated in the peripheral segment of the oculomotor nerve as it leaves the brain stem.

View Article and Find Full Text PDF
Article Synopsis
  • The case study discusses a 32-year-old woman diagnosed with Guillain-Barré syndrome (GBS) linked to SARS-CoV-2, presenting unique neurological symptoms like cranial nerve dysfunction and autonomic issues.
  • After receiving treatment, her inflammatory markers and sodium levels normalized, although some symptoms like fatigue and speech difficulties persisted after nine months.
  • This highlights the complex neurological effects of COVID-19, indicating a need for further research into its underlying mechanisms and treatment options for affected patients.
View Article and Find Full Text PDF
Article Synopsis
  • - The study examines the effects of parasympathetic stimulation via the pterygopalatine ganglion (PPG) on choroidal structure, specifically looking at how electroacupuncture impacts choroidal thickness and vascularity in healthy adults.
  • - In a crossover design, 22 participants underwent both PPG stimulation and sham stimulation, with measurements taken before and after each intervention, revealing significant increases in choroidal thickness and vascularity following PPG stimulation.
  • - Results showed that while choroidal thickness peaked 15 minutes after stimulation and remained elevated for 60 minutes, choroidal vascularity peaked immediately and then gradually returned to baseline, highlighting the potential of PPG activation for influencing choroidal health
View Article and Find Full Text PDF

Head and neck paragangliomas: Recent advances in translational and clinical research and guidelines for patient care.

Best Pract Res Clin Endocrinol Metab

December 2024

Department of Otology and Skull Base Surgery, Gruppo Otologico, 29121 Piacenza, Italy.

Head and neck paragangliomas (HNPGLs), rare neuroendocrine tumors that mainly arise from parasympathetic ganglia along the cranial nerves, are challenging due to anatomic origin, tendency to aggressive neurovascular and skull base infiltration, unpredictable metastatic potential, radio-chemoresistance, and risk of multiplicity. Symptoms range from mild to life threatening depending on location/size, but rarely relate to catecholamine excess. Risk factors include female sex and pathogenic germline variants in genes affecting hypoxia signaling (foremost succinate dehydrogenase genes).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!