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Carlos M. Villalón - One of the best experts on this subject based on the ideXlab platform.
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effects of two isometheptene enantiomers in isolated human blood vessels and rat middle Meningeal Artery potential antimigraine efficacy
Journal of Headache and Pain, 2019Co-Authors: Alejandro Labastidaramirez, Eloisa Rubiobeltran, Kristian Agmund Haanes, Rene De Vries, Ruben Dammers, Ad J.j.c. Bogers, Antoon J Van Den Bogaerdt, Bruce L. Daugherty, Alexander H. J. Danser, Carlos M. VillalónAbstract:Racemic isometheptene [(RS)-isometheptene] is an antimigraine drug that due to its cardiovascular side-effects was separated into its enantiomers, (R)- and (S)-isometheptene. This study set out to characterize the contribution of each enantiomer to its vasoactive profile. Moreover, rat neurogenic dural vasodilatation was used to explore their antimigraine mechanism of action. Human blood vessel segments (middle Meningeal Artery, proximal and distal coronary arteries, and saphenous vein) were mounted in organ baths and concentration response curves to isometheptene were constructed. Calcitonin gene-related peptide (CGRP)-induced neurogenic dural vasodilation was elicited in the presence of the enantiomers using a rat closed cranial window model. The isometheptene enantiomers did not induce any significant contraction in human blood vessels, except in the middle Meningeal Artery, when they were administered at the highest concentration (100 μM). Interestingly in rats, (S)-isometheptene induced more pronounced vasopressor responses than (R)-isometheptene. However, none of these compounds affected the CGRP-induced vasodilator responses. The isometheptene enantiomers displayed a relatively safe peripheral vascular profile, as they failed to constrict the human coronary Artery. These compounds do not appear to modulate neurogenic dural CGRP release, therefore, their antimigraine site of action remains to be determined.
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characterisation of cgrp receptors in the human isolated middle Meningeal Artery
Life Sciences, 2006Co-Authors: Saurabh Gupta, Carlos M. Villalón, Suneet Mehrotra, C J J Avezaat, Pramod R Saxena, Antoinette MaassenvandenbrinkAbstract:Although the understanding of migraine pathophysiology is still incomplete, there seems to be little doubt that dilatation of cranial blood vessels, including Meningeal arteries, is involved in the headache phase of migraine. Since calcitonin gene-related peptide (CGRP) has been implicated in this vasodilatation, the present study set out to compare the relaxant effects of the endogenous ligand h-alphaCGRP, and [ethylamide-Cys(2,7)]h-alphaCGRP ([Cys(Et)(2,7)]h-alphaCGRP), a CGRP(2) receptor agonist, on human isolated middle Meningeal Artery segments, precontracted with KCl. Classical Schild plot analysis was used to characterise the receptor population in this Artery using BIBN4096BS and h-alphaCGRP(8-37) as antagonists. h-alphaCGRP relaxed arterial segments more potently than [Cys(Et)(2,7)]h-alphaCGRP (pEC(50): 8.51+/-0.16 and 7.48+/-0.24, respectively), while the maximal responses to these agonists were not significantly different. BIBN4096BS equipotently blocked the relaxations induced by both agonists with a pA(2) of approximately 10 and with a Schild plot slope not significantly different from unity. h-alphaCGRP(8-37) also antagonised the response to h-alphaCGRP with a pA(2) of 6.46+/-0.16 and a Schild plot slope not different from unity. Furthermore, the results obtained from RT-PCR studies confirmed the presence of all the essential components required for a functional CGRP(1) receptor in these arteries. Considering the high antagonist potency of BIBN4096BS, coupled to the lower agonist potency of [Cys (Et)(2,7)]h-alphaCGRP, it is reasonable to suggest a predominant role of CGRP(1) receptors in the human middle Meningeal Artery. This view is reinforced by Schild plot analysis, which revealed a slope of unity in all experiments, giving further evidence for a homogeneous CGRP receptor population in this vascular preparation.
Robert F Spetzler - One of the best experts on this subject based on the ideXlab platform.
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Posterior inferior cerebellar Artery origin thrombosis with aneurysm of collateralized posterior Meningeal Artery presenting as subarachnoid hemorrhage: case report.
Neurosurgery, 2009Co-Authors: Steven W Chang, Udaya K Kakarla, Giriraj K Sharma, Robert F SpetzlerAbstract:Objective This is the first report of a ruptured aneurysm involving a collateral branch to the posterior inferior cerebellar Artery (PICA) in a patient who had a subarachnoid hemorrhage. Clinical presentation A 56-year-old man initially presented with a subarachnoid hemorrhage and underwent 2 catheter-based 4-vessel angiograms with negative results. A delayed angiogram 4 weeks later revealed a dissecting aneurysm of the posterior Meningeal Artery, a branch of the vertebral Artery. Intervention A 3-dimensional reconstruction of the vertebral angiogram showed proximal occlusion of the proximal left PICA and distal filling via a collateral branch from the posterior Meningeal Artery. A far-lateral approach was used for this patient. The aneurysm was found along the course of the collateral posterior Meningeal Artery and was clipped successfully. Conclusion Aneurysms involving collateral branches of the PICA are rare. It is important to recognize such collateral flow preoperatively because inadvertent sacrifice of these vessels during a surgical approach could lead to stroke and neurological deficits of the PICA territory.
Ankit Khandelwal - One of the best experts on this subject based on the ideXlab platform.
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an undocumented variation involving auriculotemporal nerve inferior alveolar nerve and middle Meningeal Artery
International Journal of Research in Medical Sciences, 2014Co-Authors: Sunita Kalra, Swati Thamke, Ankit KhandelwalAbstract:Auriculotemporal nerve typically has two roots, encircling the middle Meningeal Artery, one anterior to it and another posterior to it as well as maxillary Artery. The middle Meningeal Artery is largest of the Meningeal arteries, ascends between the sphenomandibular ligament and lateral pterygoid muscle and traverses between the roots of the auriculotemporal nerve before entering the cranial cavity through the foramen spinosum. The knowledge of the neurovascular relationships of the infratemporal region is significant in surgical practice. We present a case of unusual communication between the auriculotemporal nerve and inferior alveolar nerve together with an extraordinary change in relations with the middle Meningeal Artery. Some clinical implications that these relations may have on the development of the supplementary innervations and the surgical interventions in this region are discussed in this article.
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An undocumented variation involving auriculotemporal nerve, inferior alveolar nerve and middle Meningeal Artery
Medip Academy, 2014Co-Authors: Sunita Kalra, Swati Thamke, Ankit KhandelwalAbstract:Auriculotemporal nerve typically has two roots, encircling the middle Meningeal Artery, one anterior to it and another posterior to it as well as maxillary Artery. The middle Meningeal Artery is largest of the Meningeal arteries, ascends between the sphenomandibular ligament and lateral pterygoid muscle and traverses between the roots of the auriculotemporal nerve before entering the cranial cavity through the foramen spinosum. The knowledge of the neurovascular relationships of the infratemporal region is significant in surgical practice. We present a case of unusual communication between the auriculotemporal nerve and inferior alveolar nerve together with an extraordinary change in relations with the middle Meningeal Artery. Some clinical implications that these relations may have on the development of the supplementary innervations and the surgical interventions in this region are discussed in this article. [Int J Res Med Sci 2014; 2(4.000): 1720-1722
Steven W Chang - One of the best experts on this subject based on the ideXlab platform.
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Posterior inferior cerebellar Artery origin thrombosis with aneurysm of collateralized posterior Meningeal Artery presenting as subarachnoid hemorrhage: case report.
Neurosurgery, 2009Co-Authors: Steven W Chang, Udaya K Kakarla, Giriraj K Sharma, Robert F SpetzlerAbstract:Objective This is the first report of a ruptured aneurysm involving a collateral branch to the posterior inferior cerebellar Artery (PICA) in a patient who had a subarachnoid hemorrhage. Clinical presentation A 56-year-old man initially presented with a subarachnoid hemorrhage and underwent 2 catheter-based 4-vessel angiograms with negative results. A delayed angiogram 4 weeks later revealed a dissecting aneurysm of the posterior Meningeal Artery, a branch of the vertebral Artery. Intervention A 3-dimensional reconstruction of the vertebral angiogram showed proximal occlusion of the proximal left PICA and distal filling via a collateral branch from the posterior Meningeal Artery. A far-lateral approach was used for this patient. The aneurysm was found along the course of the collateral posterior Meningeal Artery and was clipped successfully. Conclusion Aneurysms involving collateral branches of the PICA are rare. It is important to recognize such collateral flow preoperatively because inadvertent sacrifice of these vessels during a surgical approach could lead to stroke and neurological deficits of the PICA territory.
Krishna Raja Rao Holavanahalli - One of the best experts on this subject based on the ideXlab platform.
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communicating root of auriculotemporal nerve with inferior alveolar nerve looping around accessory Meningeal Artery
International Journal of Research in Medical Sciences, 2015Co-Authors: Shakuntala Nallagatla, Manivannan Karuppan, Gangadhara Muninarayanaswamy, Krishna Raja Rao HolavanahalliAbstract:Background: The auriculotemporal nerve has been described as having two roots in standard textbooks of anatomy. It lies on the tensor veli palatini muscle while passing backwards behind the lateral pterygoid muscle. It runs behind the temporomandibular joint after passing between the sphenomandibular ligament and the neck of mandible. It ascends over the posterior root of zygoma posterior to superficial temporal vessels. It gives superficial temporal branches and also branches to facial nerve and otic ganglion. The branches to the facial nerve join at the posterior border of masseter. On the face the cutaneous branches supply the tragus, part of the adjoining auricle of the ear and posterior part of temple. Methods: Variations in the origin of the auriculotemporal nerve have been described by many authors in the past and this prompted the study of the auriculotemporal nerve, its origin and course, in 36 specimens (18 cadaveric heads) in bodies that were allotted for dissection purpose to first year medical students in the department of anatomy in P.E.S Medical College, Kuppam. Results: It was seen that the auriculotemporal nerve had two roots of origin and they formed a loop to enclose the middle Meningeal Artery in all the 35 specimens except in one side of the cadaveric heads. In only one half of a cadaveric head it was found to arise by three roots which formed two nerve loops. The first and second nerve roots joined with each other to form a nerve loop. The third root joined with the inferior alveolar nerve and formed the second nerve loop. The accessory Meningeal Artery passed through the second nerve loop. The normal presentation of two roots enclosing the middle Meningeal Artery was not present. Instead the accessory Meningeal Artery was enclosed between the third root and the inferior alveolar nerve. The middle Meningeal Artery entered the skull through the foramen spinosum as usual but was not enclosed by the nerve roots. The trunk of the auriculo temporal nerve was seen between the middle Meningeal Artery and inferior alveolar nerve and the study reports the presence of variant nerve loops encircling the accessory Meningeal Artery. Conclusion: The variations in the roots of auriculotemporal nerve have been reported in the past and since it is important in the clinical implications of the region especially for the facio-maxillary surgeons and dental surgeons. The incidence of variation has to be documented as this helps in updating the clinical database for surgical procedures and treatment in the region of infratemporal fossa.
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Communicating root of auriculotemporal nerve with inferior alveolar nerve-looping around accessory Meningeal Artery
Medip Academy, 2015Co-Authors: Shakuntala Nallagatla, Manivannan Karuppan, Gangadhara Muninarayanaswamy, Krishna Raja Rao HolavanahalliAbstract:Background: The auriculotemporal nerve has been described as having two roots in standard textbooks of anatomy. It lies on the tensor veli palatini muscle while passing backwards behind the lateral pterygoid muscle. It runs behind the temporomandibular joint after passing between the sphenomandibular ligament and the neck of mandible. It ascends over the posterior root of zygoma posterior to superficial temporal vessels. It gives superficial temporal branches and also branches to facial nerve and otic ganglion. The branches to the facial nerve join at the posterior border of masseter. On the face the cutaneous branches supply the tragus, part of the adjoining auricle of the ear and posterior part of temple. Methods: Variations in the origin of the auriculotemporal nerve have been described by many authors in the past and this prompted the study of the auriculotemporal nerve, its origin and course, in 36 specimens (18 cadaveric heads) in bodies that were allotted for dissection purpose to first year medical students in the department of anatomy in P.E.S Medical College, Kuppam. Results: It was seen that the auriculotemporal nerve had two roots of origin and they formed a loop to enclose the middle Meningeal Artery in all the 35 specimens except in one side of the cadaveric heads. In only one half of a cadaveric head it was found to arise by three roots which formed two nerve loops. The first and second nerve roots joined with each other to form a nerve loop. The third root joined with the inferior alveolar nerve and formed the second nerve loop. The accessory Meningeal Artery passed through the second nerve loop. The normal presentation of two roots enclosing the middle Meningeal Artery was not present. Instead the accessory Meningeal Artery was enclosed between the third root and the inferior alveolar nerve. The middle Meningeal Artery entered the skull through the foramen spinosum as usual but was not enclosed by the nerve roots. The trunk of the auriculo temporal nerve was seen between the middle Meningeal Artery and inferior alveolar nerve and the study reports the presence of variant nerve loops encircling the accessory Meningeal Artery. Conclusion: The variations in the roots of auriculotemporal nerve have been reported in the past and since it is important in the clinical implications of the region especially for the facio-maxillary surgeons and dental surgeons. The incidence of variation has to be documented as this helps in updating the clinical database for surgical procedures and treatment in the region of infratemporal fossa. [Int J Res Med Sci 2015; 3(3.000): 626-629