Abstract
Purpose :
Pituitary adenylate cyclase-activating polypeptide (PACAP) and its receptors have been demonstrated to play a vital role in the process of neuronal apoptosis. This study investigated the expression changes of PACAP and its receptors and its association with retinal ganglion cell (RGC) death following optic nerve crush (ONC) in the rat.
Methods :
Eyes of Male Sprague–Dawley rats were enucleated 1, 3, 5, 7 and 14 days after the crush of the optic nerve. Changes of the protein and mRNA level of PACAP and its receptors, PAC1R, VPAC1R and VPAC2R in the retina after ONC were examined by western blot and Real-Time PCR analysis. Besides, immunofluorescent staining was performed to detect the localization of PACAP and its receptors.
Results :
The expression of PACAP and PAC1R increased in a time manner in ONC group (*P<0.05, **P<0.01, ***P<0.001), which reached a peak 5 days after the crush of the optic nerve. Moreover, double label immunofluorescent staining showed that PACAP and PAC1R located mainly in ganglion cell layer (GCL). Besides, both PACAP (+) cells and PAC1R (+) cells within GCL increased after ONC (PACAP positive cells, 10.7 folds, *P<0.05; PAC1R positive cells, 12.6 folds, **P<0.01). The expression of PACAP and PAC1R increased in a time manner in ONC group (*P<0.05, **P<0.01, ***P<0.001), which reached a peak 5 days after the crush of the optic nerve. Moreover, double label immunofluorescent staining showed that PACAP and PAC1R located mainly in ganglion cell layer (GCL). Besides, both PACAP (+) cells and PAC1R (+) cells within GCL increased after ONC (PACAP positive cells, 10.7 folds, *P<0.05; PAC1R positive cells, 12.6 folds, **P<0.01).
Conclusions :
We first detected that the expression of PACAP and its high affinity receptor PAC1R were remarkably increased after ONC, and mainly expressed in GCL of the retina.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.