The presence of an opioid system mediating behavioral thermoregulation in the terrestrial snail, Cepaea nemoralis.
Administration of the opiate agonist, morphine sulfate (0.1-10 micrograms per snail) resulted in a significant dose- and time-dependent increase in the temperatures selected by the terrestrial snail, Cepaea nemoralis, in a thermal gradient. These thermoregulatory effects could be blocked and reversed by naloxone hydrochloride, with the opiate antagonist by itself (1 and 10 micrograms) causing a significant decrease in preferred temperatures. After 6-10 days of daily administration of morphine, Cepaea displayed tolerance, the effects of morphine decreasing and thermal preferences becoming similar to those of saline-treated individuals. These results suggest that an opioid system is involved in the control of thermoregulation in snails, in a manner that is similar to that shown by vertebrates.
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D001833:Body Temperature Regulation; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D009020:Morphine / Q000494:pharmacology; D009270:Naloxone / Q000494:pharmacology; D011957:Receptors, Opioid / Q000502:physiology*; D012908:Snails / Q000502:physiology*; D013696:Temperature; D013997:Time Factors
D011957:Receptors, Opioid; D009270:Naloxone; D009020:Morphine