Neurology & Neurophysiology

Biography

Biography: Itaru Yazawa

Abstract

Most recent studies of motor behavior use in vitro preparations of the neonatal rodent brainstem-spinal cord and spinal cord. However, the relevance of these studies to the neural mechanisms of adult respiration/circulation and locomotion is unclear, because the neonatal brainstem and spinal cord are immature. Moreover, it has been reported that the oxygen tension in deep tissues in these preparations was extremely low compared to that in the in vivo preparations. Thus, the results obtained from these in vitro preparations might indicate the physiological phenomena produced in a hypoxic state. To overcome these difficulties in research fields using rodents, we have adapted a decerebrated and arterially perfused in situ preparation originally developed by Pickering et al., to the preparation that can investigate functional interactions between the central nervous system. For this purpose, the rodent (weighing about 5 g or more) was decerebrated and survived by a type of total artificial cardiopulmonary bypass as a means of extracorporeal circulation to deliver oxygen to the tissues of the entire body. The oxygen and ion components of body fluid required for the survival of the preparation were supplied via the blood vessels. The physiological state of this preparation resembles to that of unanesthetized rodents under hypothermia. Here we would like to introduce a decerebrated and arterially perfused in situ preparation, and talk about reciprocal functional interactions between the brainstem and the spinal cord found by using this preparation.