Influence of Morphine on Tissue Permeability and the Spreading Effect of Hyaluronidase *

Work recently reviewed by Duran-Reynals,6 in whose laboratory this investigation was carried out, has provided facts which form the basis for a concept of the permeability of connective tissue. Tissue permeability has a normal constitutional state or tonus which can be increased by certain factors and decreased by others. Of the former, the most important are the spreading factors, some of which are identified as mucolytic enzymes, hyaluronidases,4 endowed with the property of hydrolyzing the hyaluronic acid of the intercellular cement of the connective tissues, and thus promoting the spreading of materials injected intradermally. In the present investigation we report results concerning the effects exerted by morphine on tissue permeability, as shown by the distribution of India ink, suspended either in saline solution or in testicular extract (hyaluronidase), after intradermal injection.