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adult patients after tonsillectomy in a double-blind study. All the drugs relieved pain equally. Bleeding from the operative site was the most common side effect. It appeared in 28, 24 and 3% of the patients treated with indo- methacin, tilidine and pethidine, respectively. On the evenirg of the opera- tive day, the indomethacin patients received another dose of indomethacin, whereas the other patients received a placebo suppository. On the following morning, the pain score was lowest and the speech least impaired in the indo- methacin patients. After indomethacin, the axillary temperature remained below 37°C, whereas it was slightly elevated in the other groups: In all groups the blood leukocyte count was significantly increased. The control values for the excretion of prostaglandin F2a in sputum ranged from 2.9 to 3.9 ng/8 min. The values were increased by 233, 183 and 29% in pethidine, tilidine and indomethacin groups, respectively. The control values for prostaglandin E ranged from 1.5 to 1.9 ng/8 min. There was an increase of 205, 111 and 80% in the pethidine, tilidine and indomethacin groups, respec- tively. Of the drugs studiec~, pethidine was most convenient for early treat- ment of throat pain in adults and indomethacin could be used for later alleviation of pain and inflammatory responses.

Studies in the primate on the analgetic effects associated with intrathecal actions of opiates, a-adrenergic agonists and baclofen. -- T.L. Yaksh and S.V. Reddy, Anesthesiology, 54 (1981) 451--467

The effects ~f intrathecally administered opiates (morphine sulfate and meperidine), a-adrenergic agonists (clonidine and ST-91) and baclofen were examined on the shock titration threshold of macaque monkeys chronically prepared with intrathecal (I) or epidural (E) catheters. Spiny opiates pro- duced a long-lasting analgesia which was antagonized by naloxone. The order of potency was I morphine ~ I meperidine ~> E meperidine ~> E morphine. Clonidine and ST-91, also produced a dose-dependent, long-lasting elevation in the shock' titration threshold, antagonized by phentolamine, but not naloxone. L-Baclofen. but not D-baclofen, resulted in a dose-dependent elevation of shock titration threshold, which was not antagonized by naloxone. Repeated administration at 24-h intervals over a 7-day period of morphine, clonidine or baclofen, resulted in a significant reduction in the analgetic effects of each drug. Cross-tolerance between the 3 classes of agents was not observed. Intrathecal co-administration of inactive doses of ST-91 and morphine resulted in a near maximal increase in the shock titration threshold, which failed to show any significant tolerance over 21 days.

Intrathecal ST-19 and morphine produced no change in muscle strength, tendon reflexes, respiratory rate, urine formation, or the ability to locomote. Baclofen, in contrast, produced a dose-dependent decrease in muscle strength. These results clearly indicate that a powerful analgesia can be pro- duced by selectively activating adrenergic, opiate, and baclofenergic receptor systems in the spinal cord.