Amphetamine treatment during early postnatal development transiently restricts somatic growth.
OBJECTIVE
Restricted somatic growth during fetal or early postnatal periods has been suggested to serve as a predictive indicator for neuroanatomical changes and behavioral impairments during adulthood. Here, the effects of d-amphetamine sulfate (AMPH) exposure during the brain growth spurt period on this potential indicator were evaluated.


METHODS
Rats received 0, 5, 15 or 25mg/kg/day of AMPH via two daily intragastric intubations from PD4-9. Body weight data were collected every other day from PD1 to 21, and then weekly until PD59. On PD9, a subset of animals was terminated 90min after the last amphetamine treatment and the weights of the cortex, cerebellum, and brainstem were collected. Weights of these brain regions from young adult rats were also assessed on PD68.


RESULTS
AMPH exposure during early postnatal development limited somatic growth in a dose-related manner, with significantly lower body weights in animals assigned to the AMPH 25 and AMPH 15 groups. However, this was transient in nature, with no significant difference in weight observed after pups were weaned on PD21. Further, no differences in brain weight were observed at either age as a result of AMPH exposure.


CONCLUSIONS
These findings support the idea that developmental AMPH exposure transiently restricts somatic growth. Moreover, the lack of effect on brain weight shows that AMPH differentially affects somatic and brain growth. The current findings suggest that in addition to the immediate effects on body weight, amphetamine may alter the rate of growth, and increase the risk for weight-related adult diseases.
Department of Pharmaceutical Science, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA. andrewsmith@uky.edu
Andrew M
AM
Smith
Wei-Jung A
WJ
Chen
D000661:Amphetamine / Q000494:pharmacology*; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000254:growth & development; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005865:Gestational Age; D008297:Male; D009929:Organ Size; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000187:drug effects*; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D012015:Reference Standards
D000697:Central Nervous System Stimulants; D000661:Amphetamine