The antinociceptive effect of intracerebroventricularly administered prostaglandin E1in the rat

✍ Scribed by A. K. Sanyal; D. N. Srivastava; S. K. Bhattacharya

• Publisher: Springer
• Year: 1979
• Tongue: English
• Weight: 394 KB
• Volume: 60
• Category: Article
• ISSN: 0033-3158
• DOI: 10.1007/bf00432287

✦ Synopsis

It is generally accepted that prostaglandins (PGs) are nociceptive substances. However, earlier studies from this laboratory indicated that morphine analgesia, in the rat, was not only serotonin mediated, but involved PGs as well. Several PG synthesis inhibitors were shown to inhibit morphine analgesia and PGE a was shown to potentiate the antinociceptive effect of morphine. Intraperitoneal administration of PGE1, but not PGE 2 and PGF2~, elicited antinociceptive effect per se, by the radiant heat method. The present study was undertaken to confirm the antinociceptive action of PGEi, after intracerebroventricular administration, against nociceptive impulses induced by radiant heat, pressure, and high frequency electric current. PGE~ produced a dose-dependent antinociceptive effect by the radiant heat and pressure methods. It potentiated the antinociceptive action of morphine by the electrical stimulation method. The antinociceptive action of PGE 1 was not evident in 5,6dihydroxytryptamine-pretreated rats, suggesting that this effect is serotonin mediated. The present study thus confirms the antinociceptive action of PGE1 and suggests that, unlike its peripheral action, the central action of PGE 1 results in suppression of nociceptive responses which may be serotonin mediated.