Perinatal hypothyroidism in rats: persistent motivational and metabolic effects.
Five groups of female rats which were exposed to thiouracil for varying periods around the time of birth were compared with a 6th group of untreated controls in motivational, metabolic, and hormonal test situations during adolescence and adulthood. The thiouracil-treated rats displayed reduced fearfulness in lever-touching and lever-pressing tasks in operant conditioning chambers and in their initial adaptation to activity-wheel and maze apparatuses. These rats also showed hyperactivity in asymptotic running-wheel performance, increased spontaneous recovery of extinguished lever-pressing, and elevated responding in lever-pressing for variable-interval food reinforcement. A supplemental study revealed significantly greater ad libitum food and water intake and oxygen consumption in male thiouracil-treated rats and elevated serum thyroxine levels in thiouracil-treated females. In general the results indicate that perinatal thyroid deficiency engenders a chronic hypermetabolic state in both sexes which may be associated with a persistent, mild hyperthyroid condition in the case of female rats.
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D003216:Conditioning, Operant / Q000502:physiology; D004327:Drinking Behavior / Q000502:physiology; D004971:Estrus; D005108:Extinction, Psychological / Q000502:physiology; D005247:Feeding Behavior / Q000502:physiology; D005260:Female; D007037:Hypothyroidism / Q000097:blood / Q000139:chemically induced / Q000150:complications*; D008297:Male; D008660:Metabolism; D009042:Motivation / Q000502:physiology*; D009043:Motor Activity / Q000502:physiology; D011247:Pregnancy; D051381:Rats; D012055:Reinforcement Schedule; D012737:Sex Factors; D013147:Spirometry; D013889:Thiouracil; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
D014284:Triiodothyronine; D013889:Thiouracil; D013974:Thyroxine