A note on the action of usnic acid on anaesthetized cats.

Abstract

Summary.1. Experiments have been performed with usnic acid on eats anaesthetized with nembutal or, in a few cases, with chloralose.2. 10 mg sodium usnate/kg body weight caused a prompt and heavy rise in oxygen consumption accompanied by a pronounced increase in rate and amplitude of respiration and by a gradual rise in body temperature, lasting for about 5 hours and then dowly falling.3. Larger doses are as a rule lethal.4. Lethal doses cause an intense rigor mortis. This effect is opposite to the effect of vulpinic acid but similar to the Well known action of the dinitrophenols.5. In normal anaesthetized cats there is a steep rise in arterial blood sugar to a level of 300–400 mg% lasting for about the same time as the increased respiratory volume. In fasted cats the rise is much slower and somewhat smaller.6. It is concluded that the major part of the rise in arterial blood sugar is due to an increased breakdown of glycogen to glucose, but there may be increased gluconeogenesis.7. The actions of usnic acid in the cat are, in the whole, very similar to those of the dinitrophenols.