Figure 3.

Discrete changes in GLP-1R expression in the SON and PVN of the WD rat brain. A, immunostaining of GLP-1Rs in the subfornical organ (SFO), SON, PVN, arcuate nucleus (Arc), NTS, area postrema (AP), median eminence (ME), and NIL of control and 3-day WD rats. Lower 4 panels are for 1 day WD. Inset are panels showing AVP staining (red) in the PVN of control and 1 day and 3-day WD animals. The white broken circle indicates the location of the PVN magnocellular bundle that is highly enriched with AVP expressing MCNs in the rat. The boxed regions of the ME in the Arc images have been expanded to visualise the staining of axons. B, western blot of GLP-1R immunoreactive bands in total protein extracts from GLP-1R expressing brain areas from control and 3-day WD rats. The ∗ in this panel indicates non-specific bands confirmed by receptor KD. Other marked bands have been confirmed by receptor KD. A separate image of the NIL captured at lower intensity is shown. Actin is shown as the housekeeping gene. C, densitometry analysis of GLP-1R immunoreactive bands in the SON and NIL. D, summary diagram of GLP-1R expression in control and WD AVP MCNs. Integrated into this diagram are changes to the synthesis and secretion of AVP in WD. OC, optic chiasm; 3 V, third ventricle; AP, anterior pituitary; IL, intermediate lobe. Values are means + SEM of n = 5–6 animals per group. ∗∗p ≤ 0.01. Scale bars = 50 μm.