Figure 6. Effects of blocking LPAR₁-mediated signaling in vivo.

(A) Experimental paradigm illustrating in vivo pharmacological blockade of LPAR₁ signaling. (B) Whole gut transit in mice treated with AM966 as measured by carmine red transit. (C) Body weight measurements in mice treated with AM966. (D–G) Representative examples of myenteric ganglia from the colons of control and AM966-treated mice immunolabeled for DAPI (nuclei, blue), doublecortin (nascent neurons, magenta), GFAP (glia, green), and HuC/D (neurons, gray). (D) In vehicle-treated colonic tissue, doublecortin staining can be visualized in fiber tracts coursing through the myenteric plexus alongside GFAP-positive fibers. This staining pattern is largely conserved in animals injected with low-dose AM966 (E) but is generally absent at higher doses (F and G). Both moderate (F) and high doses (G) of AM966 injection appeared to promote remodeling of glial morphology in the myenteric plexus with accompanying loss of enteric neurons. This pathological pattern is characterized by diffuse, hyperintense GFAP staining (green-channel). (H) Percentage of ganglionic area of doublecortin and GFAP staining. (I) Ganglionic HuC/D+ neuron density. n = 3–5 mice in B–I, *P < .05 and **P < .01, by 1-way ANOVA with Dunnett’s test. Scale bar in D = 50 μm and it pertains to A–D.