English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The present investigation was undertaken to demonstrate how a conditional stimulus (cs) similar to the a ction of morphine, can increase rectal temperature during morphine abstinence. Also, the study implicates certain neurotra11E.rn1iters which are involved in the ef'f'ect of conditional stimulus and of morphine to affect rectal temperature. Rats were given two equally spaced injections of morphine sulfate daily, each injection being paired with a bell. The bell was presented fo r one minute and the injection was given during the last 15 seconds. This procedure was followed for lJ-15 days. Twenty-four hours after the last injection the bell was presented alone. The rats learned to increase their body temperature folloi.ving the presentation of the bell. This increase was specific only to animals that had the bell paired with morphine prior to challenge treatment. This change in temperature was shown to be approximately equivalent to an injection of 12.5 mg/Kg at 24 hr after the last morphine injection. When naive animals were exposed to a bell, no change in temperature was observed. Those rats which had received a random bell or no bell during addiction demonstrated no change in temperature when presented with the CS 24 hr after the last injection. iii Naloxone, a narcotic antagonist, produces hypothermia in normally addicted rats only if given within 12 hr after the last morphine injection. In contrast, when administered to CS-morphine paired animal s which received only the CS 24 hr after the las t morphine injection, naloxone caused a hypothermia. This data suggest that the CS and morphine a re working by either the same or parallel pathways in the brain. The CS induced increase in temperature was b locked dur ing withdrawal ~hen t h e animals we re pret reated wi th phenoxybenzamine (2 mg/Kg ), mecarnylamine (2.5 mg/Kg) , h a loperidol (0. 2 mg/Kg) and benztropine (0 . 625 mg/Kg ) but was not blocked by cyprohe ptidine (2 mg/Kg) . Morphine induced increas e in temperatur e ~~s blo cked by me camyJ.nmine, ph e n oxybenzamine and cyprohept idin e but was not blocked by haloperidol or bentropine. Propranolol (2 mg/Kg ) had little effec t on the increase in t emperature due to t he CS or morphine when given at 24 hr after the last CS-morphine pairing . The CS wa s not able to affect other withdrawal symptoms such as sha kes, ptosis, pi loerection, loss in body weight, or writhing when presented 24 hr after the last morphine dose. These data indicate that the increase in temperature elicited by morphine during withdrawal can be classically conditioned. Such a response required a functional autonomic and centra l nervous system.

Effect of Selected Drugs on Control of Morphine Withdrawal Hypothermia Induced by Morphine or Conditional Stimulus Associated with Morphine