Fig. 2
Sample of changes in fluorescence (DF/F%) induced by α-synM, which are indicative of alterations in intracellular calcium levels in LDTM and LDTF. (A) In both sexes, changes in response of the fluorescence to α-synM exhibited two different polarities, which suggested increases (A1a, A2a) or decreases (A1b, A2b) in intracellular calcium levels, respectively. Inset in A2 is a fluorescent image under 380 nm wavelength light of one of the LDTF brain slices used in this study in which two Fura 2-AM filled cells indicated with red arrows can be seen. Regions of interest were drawn around each cell and average fluorescent intensity (F) within each region of interest was plotted against time. White scale bar indicates 20 μm. (B) Histograms summarizing the data from the population of recorded cells indicating that (B1) the frequency of responses to α-synM did not significantly differ between the two sexes (LDTM: n = 38/39, LDTF: n = 89/89; p = 0.3047; Fischer’s Exact test), (B2) whereas the distribution of response polarity differed significantly between the sexes with a greater proportion of responses suggesting decreases in calcium being elicited in females than males (LDTM: n of decreases = 9/38, LDTF: n of decreases = 52/89; p = 0.0004; Fisher’s Exact test). LDTM: Laterodorsal tegmental nucleus of male; LDTF: Laterodorsal tegmental nucleus of female. *** Indicates p < 0.001