An immunofluorescence study about staining pattern variability of Sarcoglycans in rat’s cerebral and cerebellar cortex

Background: Sarcoglycans are transmembrane glycoproteins which connect extracellular matrix components to cytoskeleton. This protein system has been long studied in muscle but there are few data about its localization in non-muscular tissues. Methods and Findings: In the present report, we have conducted an indirect immunofluorescence study on normal rat’s cerebral and cerebellar cortex. Our results show that in these districts each sarcoglycan is expressed by a “spot-like” staining pattern, with spots of 0.5-2 μm average diameter, extending mainly around the soma of neurons and glial cells. In cerebral cortex, although all sarcoglycans are present, a staining pattern variability for each sarcoglycan, in the different cerebral cortex areas, exists. Instead, the pattern distribution level of sarcoglycans in cerebellar cortex doesn’t change. We also performed a statistical analysis which confirms the immunofluorescence results. Conclusions: Then, the presence of a sarcoglycans variability in cerebral cortex, where it is known the existence of several synaptic network, and the absence of a sarcoglycans variability in cerebellar cortex, where the same synaptic networks are repeated unchanged, suggest that in brain sarcoglycans may be associated with synaptic networks. Moreover, the distribution of sarcoglycans, mainly in post-synaptic regions of the neurons, suggests a role of these proteins in cellular signalling, regulating membrane receptors assembly. We also support that sarcoglycans in glial cells could be associated with the regulation of the mechanism in the brain-blood-barrier.