Amphetamine and morphine produce a conditioned taste and place preference in the house musk shrew (Suncus murinus).

Abstract

Rats have been shown to avoid consuming a flavor, but prefer a location, previously paired with amphetamine or morphine. A series of 4 experiments evaluated the hedonic properties of amphetamine and morphine in the house musk shrew (Suncus murinus), an insectivore that (unlike rats) is capable of vomiting when exposed to toxins. Unlike rats, amphetamine (20 mg/kg) and morphine (20 mg/kg) produced both a conditioned sucrose (0.3 M) and saccharin (0.1%) preference in shrews (administered intraperitoneally), when measured by both a 1- and a 2-bottle test. At the same dose, both drugs also produced a place preference in shrews. These results suggest that the potential of rewarding drugs to produce taste avoidance may vary on the basis of the ability of the species to vomit.

The 5-HT1A agonist 8-OH-DPAT dose-dependently interferes with the establishment and the expression of lithium-induced conditioned rejection reactions in rats

“…This suggestion is fortified by a recent finding in our laboratory. Parker et al (2002a) report that the Suncus murinus (house musk shrew) develops taste preference rather than taste avoidance when a novel saccharin flavor is paired with high doses of amphetamine or morphine, which also produce a place preference in this species. Yet, the shrew avoids saccharin that is paired with a dose of lithium chloride that induces vomiting (Smith et al 2001).…”

Taste avoidance and taste aversion: Evidence for two different processes

“…This suggestion is fortified by a recent finding with an animal that vomits in response to toxin exposure. Parker, Corrick, Limebeer, and Kwiatkowska (2002) reported that the Suncus murinus (house musk shrew) develops taste preference, rather than taste avoidance, when a novel saccharin flavor is paired with high doses of amphetamine or morphine, which also produce a place preference in this species. Yet the shrew avoids saccharin that is paired with lithium chloride (J. E. Smith, Friedman, & Andrews, 2001).…”

Conditioned Flavor Preference and the US Postexposure Effect in the House Musk Shrew (Suncus Murinus)

“…Indeed, this pattern of results imply the lack of a neophobic response in the house musk shrew since rats in similar studies (e.g., Kawai and Nakajima, 1997) did not show such consistent levels of intake throughout their sessions. Parker et al (2002) also reported no evidence of shrews exhibiting neophobic reactions to 0.3 M sucrose solutions, which were used in our study as the US. Ishii et al (2000) reported that thirsty shrews continued showing a phobic response to a 0.5% vinegar solution that did not habituate even after 14 sessions.…”

“…The house musk shrews, however, just have smaller variety of selecting food relative to the omnivores, implying the system of conditioned flavor preference and habituation to novel food seems to provide relatively small adaptive benefit for shrews in terms of food choice. On the other hand, previous research (Parker et al, 2002) obtaining conditioned taste preference in the house musk shrews used amphetamine and morphine as the USs, which have strong pharmacological impact on organism. It may be possible that shrews could form association between taste and pharmacological effect although nutritional effect, using in present research, has weak impact.…”

“…The only study, as far as we know, that deals with conditioned taste preference in shrews was conducted by Parker et al (2002). They found that using rewarding drugs like morphine as the US produced a conditioned taste preference to the CS in shrews, whereas rats that underwent the same procedure developed a rather aversive response to the CS (see also, e.g., Hunt and Amit, 1987).…”