Figure 2

ET-1 induces a febrile response in sham-operated but not in ovariectomized (OVX) female rats. The animals were administered ET-1 (ET-1, 1 pg, i.c.v.) or saline (Sal). (A) mean ± s.e.mean of body temperature variation (°C) in each group (n = 4–7). *p < 0.05 compared with the saline group, ^#p < 0.05 when compared with Sham ET-1 group. (B–I) Representative confocal images of hypothalamic samples from sham-operated and OVX female rats, treated with LPS 50 µg/kg, i.p. or saline (100×). Groups are indicated at the left of each row. Panels B, D, F and H show immunoreactivity for ET_B receptors (red), while panels C, E, G and I show merged images representing the red (ET_B), the blue (cell nuclei, DAPI), and the green (astrocytes, GFAP) channels. Arrows point to ET_B signals. High-magnification inserts (400×) show localization in greater detail. (J) Fluorescence was quantified using ImageJ. Values are mean ± s.e.mean for ET_B fluorescence intensity (arbitrary units, UA). *p < 0.05 when compared with OVX Sal group; ^#p < 0.05 when compared with Sham LPS group.