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Neural Control of the Intestinal Circulation and its Interaction With Autoregulation
Published in Irving H. Zucker, Joseph P. Gilmore, Reflex Control of the Circulation, 2020
Gerald A. Meininger, Harris J. Granger
Origin and Distribution of Parasympathetic Innervation. Parasympathetic nerves to the digestive organs arise as preganglionic fibers from the cranial (VII, IX, and X) and sacral (S2–S4) portions of the spinal cord. The VII and IX cranial nerves supply the salivary glands, whereas the X cranial nerve (Vagus) supplies the majority of the visceral organs. The sacral parasympathetic outflow is contained in the pelvic nerve that distributes nerve fibers to the colon and bladder. Preganglionic parasympathetic nerve fibers enter the digestive organs to form synapses with the extensive enteric neurons of the myenteric or submucosal nerve plexi. The neurotransmitter at this synapse is acetylcholine. Postganglionic fibers also utilize acetylcholine as a neurotransmitter. Although parasympathetic nerves are recognized to play an important role in regulation of gastrointestinal function, their role in vasoregulation has been less clear.
Psychoneuroimmunology, Stress and Infection
Published in Herman Friedman, Thomas W. Klein, Andrea L. Friedman, Psychoneuroimmunology, Stress, and Infection, 2020
Each of these factors has been shown to influence cells of the immune system in vitro, and many of them may have similar effects in vivo. Although the actions of each of these chemical messengers are complex, for the most part, the peptides have facilitatory effects. The sympathetic innervation of organs such as the spleen, the thymus and the lymph nodes may play important regulatory functions. A potential parasympathetic innervation has not been confirmed.12
Interventional Therapies for Essential Hypertension
Published in Giuseppe Mancia, Guido Grassi, Konstantinos P. Tsioufis, Anna F. Dominiczak, Enrico Agabiti Rosei, Manual of Hypertension of the European Society of Hypertension, 2019
Konstantinos P. Tsioufis, Kyriakos Dimitriadis, Alex Kasiakogias, Vassilios Papademetriou
The vagus nerve is the main provider of parasympathetic innervation of the heart. Preclinical data has shown that vagal nerve stimulation may reduce BP without producing bradycardia or bradypnea (30). An implantable vagal nerve neuro stimulator system has been tested in patients with heart failure, with improvements in left ventricular dimensions and functional capacity (31). Electrical stimulation is reversible by switching off the device. In a randomised placebo-controlled trial, transcutaneous vagus nerve stimulation via the auricular branch performed in 30 healthy individuals was associated with improvements in baroreflex sensitivity (32).
Accommodative and convergence anomalies in patients with opioid use disorder
Published in Clinical and Experimental Optometry, 2022
Mohaddeseh Ghobadi, Payam Nabovati, Hassan Hashemi, Ali Talaei, Hamid Reza Fathi, Yeganeh Yekta, Hadi Ostadimoghaddam, Abbasali Yekta, Mehdi Khabazkhoob
Some theories can be proposed for this high prevalence of accommodative insufficiency and accommodative infacility in patients with OUD. This finding may be due to changes in the sympathetic or parasympathetic innervation to the ciliary muscle via direct effects of opioids on the CNS. It should be noted that disturbance of balance in sympathetic/parasympathetic innervation to the ciliary muscle has been suggested as one of the possible causes of reduced AA in some studies.20–22 Another possible cause is pupillary miosis, which has been identified as a common complication in OUD patients.23,24 Although miosis occurs due to the effect of opioids on the CNS, the exact mechanism of opioid-related pupillary miosis is still unclear. Theories have been proposed in this regard, including direct stimulation of the Edinger Westphal (EW) nucleus, depression of cortical centres that normally inhibit EW, and stimulation of opioid receptors located on the iris sphincter.11,25 Pupillary miosis increases the depth of focus, which is associated with the need for less accommodative effort. This phenomenon can lead to reduced accommodative amplitude and facility over time. An interesting finding of this study was the significant inverse relationship between accommodative insufficiency and accommodative infacility with the pupil size after controlling for the effect of age, duration of opioid abuse, and refractive error, which is line with this theory.
Quantitative Evaluation of Pupil Responses in Patients with Prolactinomas Being Treated with Dopamine Agonists
Published in Neuro-Ophthalmology, 2022
Sedat Ava, Leyla Hazar, Mine Karahan, Seyfettin Erdem, Mehmet Emin Dursun, Zafer Pekkolay, Uğur Keklikçi
Normally, pupil responses are controlled by the autonomic nervous system. In the function of the PNS, acetylcholine as a neurotransmitter causes miosis in the pupil by stimulating the muscarinic receptors in the circular muscles of the iris, while in the function of the SNS, mydriasis occurs in the pupil when noradrenaline as a neurotransmitter stimulates the α-adrenergic receptors in the radial muscles of the iris.16 Sympathetic innervation is provided by the ipsilateral hypothalamus, while parasympathetic innervation is provided by the Edinger–Westphal nucleus located in the upper midbrain.17 Pupil responses normally reflect a balance between the SNS and PNS (between noradrenaline and acetylcholine) in the autonomic nervous system. In static pupillary function tests, PDs in dark environments show SNS function, whereas PDs in light environments show PNS function. Conversely, while the dilatation status (velocity and amplitude) of the pupil in dynamic tests indicates SNS function, the contraction status of the pupil (velocity and amplitude) indicates PNS function.
OnabotulinumtoxinA injection towards the SPG for treating symptoms of refractory chronic rhinosinusitis with nasal polyposis: a pilot study
Published in Acta Oto-Laryngologica, 2021
Kent Are Jamtøy, Erling Tronvik, Daniel Fossum Bratbak, Joan Crespi, Lars Jacob Stovner, Irina Aschehoug, Wenche Moe Thorstensen
The risk of serious and permanent side effects of current surgical procedures shows that novel, minimally invasive, and well-tolerated approaches are needed. A recent study has demonstrated that there is a benefit when combining traditional surgery (FESS) with resection of the parasympathetic innervation [11]. We would therefore expect a more significant reduction in sinonasal symptoms combining the procedure with traditional surgery and biological treatment (monoclonal antibodies) for CRSwNP. Despite patients having severe symptoms related to CRSwNP the present study showed a significant reduction in nasal obstruction without direct surgery. We think the results are promising and believe a larger randomized, controlled study, should be performed. After that, a natural next step could be to combine the procedure with traditional surgery or biological treatment to evaluate the procedure in a more realistic clinical setting.