Universidad Autonoma del Estado de Mexico 1 article published in JoVE Biology Immunohistochemistry Techniques to Analyze Cellular Proliferation and Neurogenesis in Rats Using the Thymidine Analog BrdU Mario Buenrostro-Jauregui*1, Alejandro Tapia-de-Jesús1, Jesus Mata1, Luis Miguel Rodríguez-Serrano1, María Elena Chávez-Hernández1, Florencia Mata1, Marco Monroy-Plasencia1,2, Aixchell Camila Alonso-Flores1, Perla Leal-Galicia*1 1Laboratorio de Neurociencias, Departamento de Psicología, Universidad Iberoamericana Ciudad de México, 2Facultad de Ciencias, Universidad Autónoma del Estado de México This paper presents four of the most common techniques for visualizing BrdU positive cells to measure adult neurogenesis in rats. This work includes instructions for reagent preparation, thymidine analog administration, transcardial perfusion, tissue preparation, peroxidase immunohistochemical reaction, immunofluorescence, signal amplification, counterstaining, microscopy imaging, and cell analysis.