Figure 4.

A ₁, A ₂, High magnification of serial sections from a mossy fiber terminal demonstrates that NAPE-PLD is present on cisternae of SER, but rarely on synaptic vesicles or on the plasma membrane. B, A similar subcellular localization is found in Schaffer collaterals in CA1. C, Quantitative analysis of subcellular immunogold distribution confirms the preferential localization of NAPE-PLD on cisternae of SER. Note that size limitations in immunogold labeling and the dense packing of synaptic vesicles (V) in mossy terminals exclude unequivocal determination of gold particle position in several cases; this category is indicated as SER/V. Nevertheless, the ratio of gold particles found on either SER or V is significantly different (Mann–Whitney U test; n = 4 mice indicated as m1–m4). PM, Plasma membrane. Scale bar, 100 nm.