%0 Journal Article
%T Influence of the Cholinergic System on the Immune Response of Teleost Fishes: Potential Model in Biomedical Research
%A G. A. Toledo-Ibarra
%A A. E. Rojas-Mayorqu¨ªn
%A M. I. Gir¨®n-P¨¦rez
%J Journal of Immunology Research
%D 2013
%R 10.1155/2013/536534
%X Fishes are the phylogenetically oldest vertebrate group, which includes more than one-half of the vertebrates on the planet; additionally, many species have ecological and economic importance. Fish are the first evolved group of organisms with adaptive immune mechanisms; consequently, they are an important link in the evolution of the immune system, thus a potential model for understanding the mechanisms of immunoregulation. Currently, the influence of the neurotransmitter acetylcholine (ACh) on the cells of the immune system is widely studied in mammalian models, which have provided evidence on ACh production by immune cells (the noncholinergic neuronal system); however, these neuroimmunomodulation mechanisms in fish and lower vertebrates are poorly studied. Therefore, the objective of this review paper was to analyze the influence of the cholinergic system on the immune response of teleost fish, which could provide information concerning the possibility of bidirectional communication between the nervous and immune systems in these organisms and provide data for a better understanding of basic issues in neuroimmunology in lower vertebrates, such as bony fishes. Thus, the use of fish as a model in biomedical research may contribute to a better understanding of human diseases and diseases in other animals. 1. Immune System in Teleost Fishes Fishes are the phylogenetically oldest vertebrate group and appeared >560 million years ago. This group includes >27,000 species, representing more than one half of the vertebrates on the planet. The vast majority of fishes are teleosts (teleostei, possessing a bony skeleton) and some are noted for their ecological and economic importance, whereas other species are widely used as biological models for genomic studies and developmental biology [1, 2]. In addition, because these organisms are the first that present adaptive immune mechanisms (Figure 1), the Big Bang of Immunology [3], the study of the immune system of these organisms is of great relevance because it provides information on the evolution of the immune system in vertebrates, thus supporting the understanding of basic aspects of immunology, therefore the possible treatment of emerging diseases in humans and in other animals [4]. Figure 1: Main humoral, cellular, and anatomical components of the immune system in fishes. Fish lymphoid organs: pronephros (1), spleen (2), and thymus (3). 1.1. Lymphoid Organs Fishes, unlike mammals, lack lymph nodes and bone marrow [5]. However, the anterior kidney or pronephros, analog evolutionary of the bone marrow,
%U http://www.hindawi.com/journals/jir/2013/536534/