RESUMEN
Unlike other mammalian AQPs, multiple tetramers of AQP4 associate in the plasma membrane to form peculiar structures called Orthogonal Arrays of Particles (OAPs), that are observable by freeze-fracture electron microscopy (FFEM). However, FFEM cannot give information about the composition of OAPs of different sizes, and due to its technical complexity is not easily applicable as a routine technique. Recently, we employed the 2D gel electrophoresis BN-SDS/PAGE that for the first time enabled the biochemical isolation of AQP4-OAPs from several tissues. We found that AQP4 protein is present in several higher-order complexes (membrane pools of supra-structures) which contain different ratios of M1/M23 isoforms corresponding to AQP4-OAPs of different size. In this paper, we illustrate in detail the potentiality of 2D BN/SDS-PAGE for analyzing AQP4 supra-structures, their relationship with the dystrophin glycoprotein complex and other membrane proteins, and their role as a specific target of Neuromyelitis Optica autoantibodies.
Asunto(s)
Acuaporina 4/química , Animales , Acuaporina 4/metabolismo , Astrocitos/metabolismo , Autoanticuerpos/química , Autoanticuerpos/metabolismo , Encéfalo/metabolismo , Membrana Celular/química , Membrana Celular/metabolismo , Células Cultivadas , Distrofina/química , Distrofina/genética , Distrofina/metabolismo , Electroforesis en Gel Bidimensional , Electroforesis en Gel de Poliacrilamida , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Ratones , Ratones Noqueados , Neuromielitis Óptica/inmunología , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Multimerización de Proteína , Estructura Cuaternaria de Proteína , RatasRESUMEN
OBJECTIVE: To compare the efficacy of two modalities of local anesthesia for diagnostic hysteroscopy in different steps of the procedure in terms of pain control and time required for the examination. STUDY DESIGN: One hundred eighty women undergoing diagnostic hysteroscopy were included in the study and randomly allocated to one of two groups. Group A (n = 88), treated with prilocaine plus lidocaine cream, and group B (n = 92), treated with lidocaine spray, were compared with group C, a control group (n = 165), including all the hysteroscopies performed without anesthesia in the same period. Duration of the hysteroscopic examination was recorded; intensity of pain induced by the procedure and shoulder pain 10 minutes after the end of the examination were recorded for all patients on the basis of a four-point pain scale. RESULTS: Duration of the procedure required was two minutes in a significantly lower percentage of patients in group A as compared to groups B and C. Furthermore, in group A we found a significant reduction in pain at placement of the tenaculum in comparison to groups B and C. In groups A and B, no patient experienced a "very painful" grade of pain versus 4.8% in group C. The vasovagal reaction rate was also significantly lower in both treated groups in comparison to the control group. Furthermore, the intensity of shoulder pain was significantly lower in the group receiving prilocaine plus lidocaine cream as compared to the other two groups. CONCLUSION: Local anesthesia has a beneficial effect, at least in those hysteroscopies presumed to be, for whatever reasons, more cumbersome to perform. Prilocaine plus lidocaine cream was more effective than lidocaine spray in decreasing pain at placement of the tenaculum and shoulder pain after the procedure.