Pharmacology
-
To investigate the mechanism of lidocaine's effect to cause vasorelaxation, swine epicardial mid-right coronary arterial rings were placed under constant (5 g) tension in a muscle bath, precontracted with 35 mmol/l KCl and exposed to increasing concentrations of lidocaine (3-2,000 micrograms/ml). At a concentration of 10 micrograms/ml, mild vasoconstriction occurred, increasing tension 1.9 +/- 0.1% above baseline. Vasodilation began to occur at 30 micrograms/ml and was maximal at 2,000 micrograms/ml, reducing tension 97.5 +/- 0.2% below baseline. Vasodilation was not altered significantly by removal of endothelium or by pretreatment with propranolol or indometacin.
-
Sennosides and related compounds are presumed to be severe cell poisons after prolonged ingestion. Some histological and ultrastructural studies in animals and man with such laxative misuse have revealed myenteric plexus and colonic epithelium injuries; but others have failed to point out identical data. ⋯ Electron microscopic observations showed nervous myenteric plexus abnormalities only in 1,8-dihydroxyanthraquinone-treated animals. These results suggest that sennosides have a good intestinal mucosa tolerance as opposed to aglycosidic-related compounds.
-
Laxatives are classified according to their actions on the gut, and the special role and use of senna in the treatment of constipation are discussed. Standardised senna is the most physiological of all the non-fibre laxatives and is safe when used in appropriate dosage avoiding loose stools. Additional advice on bulk supplement should be given.
-
To investigate the role of endogenous opioids on ventilatory control in pentobarbitone-anesthetized rats, the opioid antagonists naloxone and naltrexone were studied for their effects on ventilation, arterial blood gases and on ventilatory responses to hypoxia and carbon dioxide. In animals breathing room air, intravenous administration of naloxone and naltrexone (4 and 10 mg/kg) caused a dose-related increase in tidal volume, respiratory rate and minute volume. These ventilatory responses were rapid in onset and were associated with a decrease in arterial PaCO2, an increase in arterial pH and an increase in arterial PaO2. ⋯ In conclusion, our results demonstrate that naloxone and naltrexone caused hyperventilation in pentobarbitone-anesthetized rats. This effect was probably triggered by stimulation of the peripheral arterial chemoreceptors and did not involve mechanisms directly associated with the central nervous system. However, endogenous opioids were not involved in the chemical control of breathing in pentobarbitone-anesthetized rats since ventilatory responses to hypoxia and carbon dioxide were not changed by administration of these opioid antagonists.
-
Randomized Controlled Trial Comparative Study Clinical Trial
Oral analgesic efficacy of suprofen compared to aspirin, aspirin plus codeine, and placebo in patients with postoperative dental pain.
The purpose of this study was to evaluate the analgesic efficacy and safety of single oral doses of suprofen 200 and 400 mg, compared with aspirin 650 plus codeine 60 mg, aspirin 650 mg, and placebo in the relief of moderate to severe pain resulting from the surgical removal of impacted third molars. 157 patients completed a randomized, double-blind, single-dose, stratified, parallel-groups trial, and were observed for at least 4 h. Based upon each of the summary efficacy measures, sum pain intensity difference (SPID), percent SPID, TOTPAR and a global evaluation, all four active treatments were approximately equally effective and all were statistically superior to placebo. ⋯ Side effects were minimal; there was one in the suprofen 200 mg, three in the aspirin 650 mg, and one in the placebo treatment group. Thus, it appears that suprofen at 200 and 400 mg is a safe and effective oral analgesic for the relief of moderate or severe postoperative dental pain, and it is possible that compared to aspirin 650 mg and aspirin 650 mg plus codeine 60 mg, it has a more rapid onset of action.