[Use of the technology of the genetic chip to study of the nitric oxide synthase]. / Empleo de la tecnología del Chip genético en el estudio de la óxido nítrico sintasa.

INTRODUCTION: The end of our century has been characterized by a quick scientific and technological growth. Among other, the brain, the human genome project and the computer science, they are some of the numerous fields that characterize this revolution. DEVELOPMENT: In the following work, we will show as these three fields of the knowledge have converged in a new area of the science denominated technology of the gene chip or microarrays. Although this methodology would allow the study of thousands of genes in one chip, in the following work we will center ourselves in its potential application for the study of the enzyme nitric oxide synthase (NOS), which is responsible for the production of the nitric oxide (NO). The technical base of this system is to be able to synthesize chains of DNA in a chip, which will be hybridized with the sample of interest that in turn are usually marked with fluorescent nucleotides. The results are analyzed using a sophisticated image analysis system. The relative estimate of the quantity of existent messenger in each sample will come determined by the intensity of the fluorescence, and for its comparison with internal controls. The discovery of at least three genes that are coded for NOS, as well as that of numerous allelic variations will allow a more exhaustive study of this molecule, which has been recognized by their vital importance. CONCLUSION: In this review we will put in perspective the utility of this technology in the genetic study of the enzyme NOS, and its utility for the understanding of the pathophysiology of some neurological illnesses.

Nitric oxide, stress, and depression.

Stress and depression have a significant impact on modern society. Even though their symptomatology is well characterized, little is known about the molecular mechanisms underlying these disturbing disorders. While the role of neurotransmitters such as serotonin, norepinephrine (NE), dopamine (DA), corticotropin-releasing hormone (CRH), and arginine vasopressin (AVP) has been extensively studied, new evidence suggests a role for the unique neurotransmitter nitric oxide (NO). This highly diffusible and reactive molecule is synthesized by at least three enzyme subtypes of NO synthase (NOS). The commonly known neuronal NOS subtype is localized in areas of the brain related to stress and depression. The limbic-hypothalamic-pituitary-adrenal (LHPA) axis is the core of this system. These interrelated pathways have in common the production, and negative feedback, of glucocorticoids. Within these areas, NO is suggested to play a role in modulating the release of other neurotransmitters, acting as a cellular communicator in plasticity and development, and/or acting as a vasodilator in regulation of blood flow. This article summarizes some of the recent advances in the understanding of the role of NO in stress and depression.