Distributions of Cholinergic and Nitroxidergic Neurons in the Spinal Cord of Neonatal and Adult Rats

Abstract

The aim of the present work was to study the distributions of cholinergic and nitroxidergic neurons in the spinal cord (SC) in neonatal and adult rats. Immunohistochemical detection of choline acetyltransferase (CAT) and nitric oxide synthase (NOS) was performed in the cervical segments of the SC in neonatal (n = 5) and adult (n = 5) Wistar rats. CAT-containing neurons were found to be located in the anterior horns of the SC; occasional cells were located in the posterior horns of the gray matter of the SC, and the central gray matter and at the boundary between Rexed laminae VI and VII. Nitroxidergic neurons were located in the superficial layers of the posterior horns of the gray matter of the SC, the central gray matter, and Rexed laminae VI–VII. The SC of neonatal and adult rats was found to contain NOS-expressing cholinergic neurons. The finding of cells containing both enzymes as early as the fi rst day after birth suggested that they are formed in the rat SC during prenatal ontogeny.