Does CA1 dopaminergic system play a role in cholestasis induced hypothermia?

There is some of evidence describing that cholestasis induces hypothermia. Meanwhile, there is paucity of comprehensive data on the mechanism(s) governing this phenomenon. The present study was undertaken to determine the effect of CA1 dopaminergica system on cholestasis induced hypothermia.

Male NMRI mice weighing 25-30g, were used. Bilateral cannulae were implanted in dorsal hippocampi (CA1) for drug microinjection. Animals were randomly divided into non-operated control, sham-operated and bile duct-ligated (BDL) groups. Cholestasis was induced by means of main bile duct ligation. Body temperatures were measured before, two and four days after BDL.

Data indicated that, two and four days post BDL, the body temperature decreases as compared to the sham-operated animals, which indicates hypothermia. Intra-CA1 injection of different doses of sulpiride (SUL; 0.25, 0.5 and 0.75μg/mouse), SCH23390 (SCH; 0.125, 025 and 0.5μg/mouse), SKF38393 (SKF; 0.25, 0.5 and 1μg/mouse) and quinpirole (QUI; 0.25, 05 and 0.75μg/mouse) exerted no effect on body temperature in non-operated and sham operated mice, by themselves. Moreover, intra-CA1 injection of SUL, QUI or SKF blocked, whereas, SCH tended to increase BDL induced hypothermia.

The present data revealed that the CA1 dopaminergic system is possibly involved in the BDL induced impairment of thermoregulation.