morphine-3-glucuronide and tifluadom

The influences of morphine sulphate, morphine-3-glucuronide and tifluadom on social encounters were compared in male and female mice that were allowed to interact with an anosmic male partner. The drugs were compared, as morphine sulphate is thought to act via mu, and tifluadom via kappa opiate receptors; morphine-3-glucuronide is the breakdown product of morphine. Neither morphine sulphate nor morphine-3-glucuronide significantly influenced inter-male social encounters. However, tifluadom increased non-social and decreased social behaviour, while increasing timid/defensive activities. Tifluadom did not significantly influence the behaviour of female mice in this social encounter: in contrast both morphine sulphate and morphine-3-glucuronide decreased timid/defensive behaviour and stimulated non-social behaviour. It was concluded that the results could be explained by suggesting that morphine sulphate decreases whereas tifluadom increases timidity.

Topics: Animals; Benzodiazepines; Fear; Female; Male; Mice; Morphine; Morphine Derivatives; Receptors, Opioid; Receptors, Opioid, kappa; Receptors, Opioid, mu; Sex Factors; Social Behavior