Effect of morphine and naloxone on a defensive response of the crab Chasmagnathus granulatus

  title={Effect of morphine and naloxone on a defensive response of the crab Chasmagnathus granulatus
  author={Mariana Lozada and Arturo Romano and H{\'e}ctor Maldonado},
  journal={Pharmacology Biochemistry and Behavior},

Opioid action on response level to a danger stimulus in the crab (Chasmagnathus granulatus).

Results suggest that morphine acts through an opiate receptor to inhibit the crab's response level to a danger stimulus and the most viable one suggests a central site of action.

The effect of opioids and their antagonists on the nocifensive response of Caenorhabditis elegans to noxious thermal stimuli

The effect of the opiate morphine and opioid neuropeptides Endomorphin 1 and 2 on the thermal avoidance (Tav) behavior of Caenorhabditis elegans is explored and Naloxone and CTOP were tested in combination with the drugs.

Habituation in the crabChasmagnathus granulatus: effect of morphine and naloxone

Results concerning stimulus generalization and dishabituation strongly suggest that neither motor fatigue nor sensory adaptation can account for the response waning, and the potential value of the response habituation as a model for studying both habituation dynamics and the mechanisms that subserve it is discussed.

Modulation of the escape response by [d-Ala2]Met-enkephalin in the crab Chasmagnathus




Quantitative studies on the antagonism by naloxone of some narcotic and narcotic‐antagonist analgesics

The results suggest that the Narcotic and the narcotic‐antagonist analgesics may inhibit stretching in this assay by interacting either with two different receptors or with the same receptor in a different manner.

Tissue Redistribution of Fentanyl and Termination of Its Effects in Rats

The authors conclude that the short duration of fentanyl effect is due to its rapid redistribution from sites of action in the brain to sites of storage (muscle and fat) and biotransformation (liver).

The relationship between pharmacokinetics and pharmacodynamic action as applied to in vivo pA2: application to the analgesic effect of morphine.

The time-dependent method provides a check on the pA2 in vivo and confirms the utility of this constant in classifying receptors in agonist-antagonist combinations classified according to their kinetics.

Kinetics of intravenous and intramuscular morphine

Both studies demonstrate that morphine distribution is rapid and extensive and its t½β relatively short and IM morphine is rapidly and completely absorbed.