Sham feeding, flavor associations and diet self-selection as indicators of feeding satiety or aversive effects of peptide hormones.
We have attempted to develop a constellation of behaviors which show differential effects following the administration of putative satiety hormones (CCK-8, BBS, insulin) as opposed to effects seen following a toxin, such as LiCl. In the initial behavior assessed, sham feeding of differently paired, flavored milks (flavor paired with insulin, BBS or saline) was carried out. Male adult Sprague-Dawley rats which sham fed milk flavors paired with 16 micrograms/kg BBS showed a significant aversion of that flavor in a two-bottle taste test (compared to saline-paired flavors, p less than 0.001) but a significant preference for flavored milk paired with 0.4 and 0.75 U insulin/rat. Lower dosages of BBS (4 and 8 micrograms/kg) and insulin (0.1 U/rat) showed no significant aversion or preference when compared to saline. The second behavioral paradigm evaluated the effects of the hormones CCK-8 and BBS and the toxin, LiCl, upon self-selection of pure macronutrients. While CCK-8 reduced intake of calories by significantly lowering ingestion/selection of fats (55%, p less than 0.01 compared to saline, control injections) and carbohydrates (50%, p less than 0.01), LiCl and BBS reduced calories by decreasing selection of primarily proteins (LiCl--49%, p less than 0.03; BBS--63% at 4 micrograms/kg and 80% at 8 micrograms/kg, both p less than 0.025). In both paradigms then, BBS at doses sufficient to significantly reduce sham intake or suppress caloric ingestion in a self-selection paradigm produced behavioral effects most similar to those observed following the injection of a toxin. LiCl, rather than effects seen following other various putative satiety signals.
Vanderweele
D A
DA
Oetting
R L
RL
Jones
R E
RE
Deems
D A
DA
D000818:Animals; D001839:Bombesin / Q000008:administration & dosage / Q000633:toxicity; D002712:Chlorides / Q000008:administration & dosage; D002766:Cholecystokinin / Q000008:administration & dosage / Q000633:toxicity; D004322:Drainage; D005247:Feeding Behavior / Q000187:drug effects*; D005508:Food Deprivation; D007328:Insulin / Q000008:administration & dosage / Q000633:toxicity; D008094:Lithium / Q000008:administration & dosage; D018021:Lithium Chloride; D008297:Male; D009419:Nerve Tissue Proteins / Q000008:administration & dosage*; D051381:Rats; D011919:Rats, Inbred Strains; D012527:Satiation / Q000187:drug effects*; D012528:Satiety Response / Q000187:drug effects*; D013649:Taste / Q000187:drug effects*
D002712:Chlorides; D007328:Insulin; D009419:Nerve Tissue Proteins; D002766:Cholecystokinin; D008094:Lithium; D018021:Lithium Chloride; D001839:Bombesin