TY - JOUR
T1 - Cannabinoid agonist, CP 55,940, facilitates intake of palatable foods when injected into the hindbrain
AU - Miller, Cheryl C.
AU - Murray, Thomas F.
AU - Freeman, Kimberly G.
AU - Edwards, Gaylen L.
N1 - Funding Information:
This work was supported by funds from the Department of Physiology and Pharmacology and the College of Veterinary Medicine, University of Georgia. Support was also provided by NIH F32 DA 14165 to C.C. Miller. We also wish to thank Emmanuel Rollin for technical assistance with behavioral studies.
PY - 2004/2
Y1 - 2004/2
N2 - Cannabinoids have been shown to influence food intake, and until recently, the neural pathways mediating these effects have remained obscure. It has been previously shown that intracerebroventricular injection of delta-9- tetrahydrocannabinol (Δ9-THC) causes increased consumption of palatable foods in rats, and we postulated the involvement of the hindbrain in this cannabinoid-induced food intake. Cannulated rats (both female and male groups) trained to consume sweetened condensed milk received either lateral or fourth ventricle injections of CP 55,940 and were presented with sweetened condensed milk 15 min after injection. Rats were injected over a range of doses between 100 pg and 10 μg per rat. Milk intake was recorded for a total of 3 h. Lateral ventricle injection of CP 55,940 increased milk intake at doses in the microgram range. However, CP 55,940 was effective in increasing food intake at nanogram doses when injected into the fourth ventricle. Finally, male rats appeared to be more sensitive to CP 55,940 than female rats inasmuch as milk consumption was increased at the 1 ng dose in male rats, whereas only the 10 ng dose was effective in females. These results indicate that CP 55,940 may act in the hindbrain to influence feeding behavior in rats.
AB - Cannabinoids have been shown to influence food intake, and until recently, the neural pathways mediating these effects have remained obscure. It has been previously shown that intracerebroventricular injection of delta-9- tetrahydrocannabinol (Δ9-THC) causes increased consumption of palatable foods in rats, and we postulated the involvement of the hindbrain in this cannabinoid-induced food intake. Cannulated rats (both female and male groups) trained to consume sweetened condensed milk received either lateral or fourth ventricle injections of CP 55,940 and were presented with sweetened condensed milk 15 min after injection. Rats were injected over a range of doses between 100 pg and 10 μg per rat. Milk intake was recorded for a total of 3 h. Lateral ventricle injection of CP 55,940 increased milk intake at doses in the microgram range. However, CP 55,940 was effective in increasing food intake at nanogram doses when injected into the fourth ventricle. Finally, male rats appeared to be more sensitive to CP 55,940 than female rats inasmuch as milk consumption was increased at the 1 ng dose in male rats, whereas only the 10 ng dose was effective in females. These results indicate that CP 55,940 may act in the hindbrain to influence feeding behavior in rats.
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U2 - 10.1016/j.physbeh.2003.10.019
DO - 10.1016/j.physbeh.2003.10.019
M3 - Article
C2 - 14984793
AN - SCOPUS:1242337340
VL - 80
SP - 611
EP - 616
JO - Physiology and Behavior
JF - Physiology and Behavior
SN - 0031-9384
IS - 5
ER -