van Megen Y J, Klaassen A B, Rodrigues de Miranda J F, van Ginneken C A, Wentges B T
Department of Otorhinolaryngology, University of Nijmegen, The Netherlands.
J Allergy Clin Immunol. 1991 Feb;87(2):521-9. doi: 10.1016/0091-6749(91)90011-c.
Cholinergic nasal hyperresponsiveness in nasal allergy may be due to changes of the characteristics in muscarinic cholinergic receptors. Radioligand receptor binding and in vitro autoradiographic studies of nasal mucosa in nonallergic (NA) and allergic patients were performed to investigate this hypothesis. The heterogeneous NA group was subdivided into control individuals and patients with chronic sinusitis and vasomotor rhinitis. The 3H-(-)-Quinuclidinylbenzilate binding to muscarinic receptors in human nasal mucosa membranes was saturable and of high affinity in all groups. No significant differences could be demonstrated between the subgroups of the NA patients. In allergic patients the dissociation constants and receptor densities were significantly decreased in comparison with those of NA and with those of control individuals. No differences in agonist binding or coupling of the muscarinic receptor to the effector system via the G protein could be observed in allergic patients. In vitro autoradiographic experiments demonstrated specific 3H-(-)-Quinuclidinylbenzilate labeling of the glandular acini in NA and allergic patients. No specific labeling could be observed in the epithelium, blood vessels, or connective tissue. In conclusion, the increased sensitivity and decreased muscarinic receptor number may reflect the cholinergic-induced hypersecretion in nasal allergy but are probably too small to explain the complex allergic reaction.
鼻过敏中的胆碱能性鼻高反应性可能归因于毒蕈碱胆碱能受体特性的改变。对非过敏性（NA）和过敏性患者的鼻黏膜进行放射性配体受体结合和体外放射自显影研究，以探究这一假说。将异质性的NA组再细分为对照组个体以及患有慢性鼻窦炎和血管运动性鼻炎的患者。在所有组中，人鼻黏膜膜中与毒蕈碱受体结合的3H-（-）-喹核醇基苯甲酸酯具有饱和性且亲和力高。NA患者的亚组之间未显示出显著差异。与NA患者及对照组个体相比，过敏性患者的解离常数和受体密度显著降低。在过敏性患者中，未观察到激动剂结合或毒蕈碱受体通过G蛋白与效应系统偶联方面的差异。体外放射自显影实验显示，NA和过敏性患者的腺泡有特异性的3H-（-）-喹核醇基苯甲酸酯标记。在上皮、血管或结缔组织中未观察到特异性标记。总之，敏感性增加和毒蕈碱受体数量减少可能反映了鼻过敏中胆碱能诱导的分泌过多，但可能太小而无法解释复杂的过敏反应。
