RESUMEN
Purinergic receptors regulate the processing of neural information in the hippocampus and cerebral cortex, structures related to cognitive functions. These receptors are activated when astrocytic and neuronal populations release adenosine triphosphate (ATP) in an autocrine and paracrine manner, following sustained patterns of neuronal activity. The modulation by these receptors of GABAergic transmission has only recently been studied. Through their ramifications, astrocytes and GABAergic interneurons reach large groups of excitatory pyramidal neurons. Their inhibitory effect establishes different synchronization patterns that determine gamma frequency rhythms, which characterize neural activities related to cognitive processes. During early life, GABAergic-mediated synchronization of excitatory signals directs the experience-driven maturation of cognitive development, and dysfunctions concerning this process have been associated with neurological and neuropsychiatric diseases. Purinergic receptors timely modulate GABAergic control over ongoing neural activity and deeply affect neural processing in the hippocampal and neocortical circuitry. Stimulation of A2 receptors increases GABA release from presynaptic terminals, leading to a considerable reduction in neuronal firing of pyramidal neurons. A1 receptors inhibit GABAergic activity but only act in the early postnatal period when GABA produces excitatory signals. P2X and P2Y receptors expressed in pyramidal neurons reduce the inhibitory tone by blocking GABAA receptors. Finally, P2Y receptor activation elicits depolarization of GABAergic neurons and increases GABA release, thus favoring the emergence of gamma oscillations. The present review provides an overall picture of purinergic influence on GABAergic transmission and its consequences on neural processing, extending the discussion to receptor subtypes and their involvement in the onset of brain disorders, including epilepsy and Alzheimer's disease.
RESUMEN
Learning endocrine physiology can be challenging. Some physiological concepts are abstract, making the process of learning more difficult for students. The comprehension of basic concepts, such as chemical hormone classification, is essential to understand the differences in synthesis, secretion, transport, and mechanism of action of hormones. To assist the students on this subject, we developed an analogy between the basic concepts of hormone synthesis, transport, and mechanism of action and a bank robbery as a first approach to engage and stimulate their learning process. In the analogy, the students are asked to help identify and characterize two bank robbery crews based on a set of evidence collected by the police. The goal is to identify the general profile of lipid- and water-soluble hormones synthesis, transport, and mechanism of action on target cells. When applying the activity, the students showed a great deal of interest in solving the crime and they seemed to understand the similarities between the analogy and the subject.NEW & NOTEWORTHY Two endocrine bank robbery crews are being searched by the police. As an endocrine system student, you have been summoned to help the police solve the robberies.