Cauna N
Anat Rec. 1977 May;188(1):1-11. doi: 10.1002/ar.1091880102.
Morphological changes in cutaneous nerve endings were investigated electron microscopically in patients suffering from certain kinds of urticaria with associated itching and in normal skin in which wheals and local itching were induced either by application of nettle hairs or by intracutaneous injections of a timothy pollen extract. Skin samples were obtained with a high speed dermal punch without anesthesia from the wheal areas. It was found that some subepidermal free nerve endings derived from non-myelinated nerve fibers (penicillate endings) showed accumulations of extra-cytoplasmic glycogen which was localized in the distended spaces between the axolemma, the Schwann cell membrane and the nerve basement membrane. In some cases, the glycogen was found to be so abundant that it occupied most of the cross sectional area of the ending. No morphological changes were observed in the pappilary endings, in nerve endings of the hairs or in the autonomic terminals. The conducting segments of all cutaneous nerve fibers showed normal morphology. The unusual morphological changes that occur in some penicillate nerve endings during the wheal development indicate that these endings are involved in the skin reaction and therefore they may be the specific end organs that are associated with itch, at least in urticaria.
对患有某些伴有瘙痒的荨麻疹患者的皮肤神经末梢形态变化进行了电子显微镜研究，并对通过涂抹荨麻毛或皮内注射梯牧草花粉提取物诱发风团和局部瘙痒的正常皮肤进行了研究。在未麻醉的情况下，用高速真皮打孔器从风团区域获取皮肤样本。结果发现，一些源自无髓神经纤维的表皮下游离神经末梢（细须状末梢）显示出胞外糖原的积累，这些糖原位于轴膜、施万细胞膜和神经基底膜之间的扩张间隙中。在某些情况下，发现糖原非常丰富，占据了末梢大部分横截面积。在乳头末梢、毛发神经末梢或自主神经末梢中未观察到形态变化。所有皮肤神经纤维的传导段均显示正常形态。在风团形成过程中，一些细须状神经末梢发生的异常形态变化表明，这些末梢参与了皮肤反应，因此它们可能是至少在荨麻疹中与瘙痒相关的特定终末器官。
