GAS MICROBUBBLES IN BIOLOGY: THEIR RELEVANCE IN HISTOLOGY, TOXICOLOGY, PHYSIOLOGY, AND ANESTHESIA

Abstract

Pilot studies in 31 rats to detect gases in the brain during anesthesia demonstrated the presence of gas microbubbles in electron photomicrographs of brains taken from anesthetized and unanesthetized control animals. Gas microbubbles were numerous in specimens preserved with near-isotonic fixatives, but nearly absent in brains fixed with a substantially hypertonic fixative solution. Hypertonic fixation appears to deplete extracellular and intracellular fluid to an extent that tissue entrapped bubbles collapse and are flushed away. Using near-isotonic fixative solutions, it was shown that gas microbubbles may play important roles in Toxicology (CCl4-induced hepatotoxicity), Physiology (oxygen transport), and Pharmacology (inhalation anesthesia). Excessively hypertonic tissue fixative solutions are unsuitable for the histological study of tissue gases.

Keywords: :

• Anesthetic Mechanisms Cc14-INDUCED Hepatotoxicity Electron Microscopy Gas Microbubbles Oxygen Transport Vapor Pressures