Massachusetts General Hospital

Research

Research Areas

• Cortical mechanisms of general anesthetic-induced loss of consciousness
• Neural functional connectivity in the cerebral cortex under general anesthesia
• The mechanisms of general anesthetic inhibition of higher-order neurons
• Neural and behavioral recovery from general anesthesia
• Advanced analysis of neural activities (e.g. spike@ local field potential relationship)
• Establishing a non-human primate model for anesthesia mechanism research

Description of Research

My goal in research is to understand how and where in the brain general anesthetics induce behavioral changes (e.g. loss of consciousness), using a multidisciplinary approach, including behavioral and systems neuroscience, electrophysiology, and molecular and cellular biology. My current project focuses on the cortical neural mechanisms of general anesthesia and we have recently developed a non-human primate model in order to fully describe the dynamic features of neural change during the awake  anesthetized continuum. In this model, we record both cortical single neuron activities and local field potentials simultaneously from multiple cortical areas, along with the animals behavioral response. Preliminary studies indicate that the anima?s loss of responsiveness coincides with distinct sequential changes in neural synchronization, strongly suggesting significant change in functional connectivity (presented in 2012 at IARS and ASA). The work may lead not only to better neurophysiological monitors to prevent intraoperative awareness and safer anesthesia, but also to understanding of a fundamental question: how consciousness arises in the brain.

Publications

• Ishizawa Y, Ma HC, Dohi S, Shimonaka H. Effects of cholinomimetic injection into the brain stem reticular formation on halothane anesthesia and antinociception in rats. J Pharmacol Exp Ther. 2000;293(3):845-51.
• Ishizawa Y, Sharp R, Liebman PA, Eckenhoff RG. Halothane binding to a G protein coupled receptor in retinal membranes by photoaffinity labeling. Biochemistry. 2000;39(29):8497-502.
• Ishizawa Y. Selective blockade of muscarinic receptor subtypes in the brain stem reticular formation in rats: effects on anesthetic requirements. Brain Res. 2000;873(1):124-6.
• Ma HC, Dohi S, Wang YF, Ishizawa Y, Yanagidate F. The antinociceptive and sedative effects of carbachol and oxycodone administered into brainstem pontine reticular formation and spinal subarachnoid space in rats. Anesth Analg. 2001;92(5):1307-15. PMID:11323367
• Ishizawa Y, Pidikiti R, Liebman PA, Eckenhoff RG. G protein-coupled receptors as direct targets of inhaled anesthetics. Mol Pharmacol. 2002;61(5):945-52. PMID:11961111
• Peterlin Z, Ishizawa Y, Araneda R, Eckenhoff R, Firestein S. Selective activation of G-protein coupled receptors by volatile anesthetics. Mol Cell Neurosci. 2005;30:506-512.
• Ishizawa Y. Mechanisms of Anesthetic Actions and the Brain. Journal of Anesthesia. 2007;21:187-199. PMID:17458649
• Ishizawa Y.General Anesthetic Gases and the Global Environment. Anesthesia & Analgesia. 112:213-217, 2011 PMID:21048097

Selected publications