Structural Alterations of Skeletal Muscle Induced by Chronic Administration of D-Amphetamine and Food Restriction

Amphetamines are frequently used as anorexigenic drugs to facilitate fasting and weight loss, although some side effects are known. The objective of the study was to study the effects of fasting induced by amphetamine administration as compared to food restriction alone on skeletal muscle. Twelve male Wistar rats were assigned to three groups: One group (AMPH) received d-amphetamine sulphate during 14 days (20 mg/Kg/day, s.c.); group FRES was the pair-fed, food restricted control receiving each day the same quantity of food consumed by the AMPH group the day before; a control group (CONT) was fed ad libitum. Food intake and body weights were controlled daily. After 14 days the animals were sacrificed and the soleus muscles were removed for light and electron microscopical evaluation and muscle fiber morphometry. Towards the end of the experimental period, food intake returned to normal in the AMPH group due to amphetamine tolerance. The AMPH and FRES animals experienced a comparable weight loss of about 15%. The muscles fibers of the AMPH and FRES group showed a slightly (n.s.) higher incidence of central nuclei than the CONT group. Their muscle fibers atrophied by about 25%. Signs of degeneration and regeneration were observed at the ultrastructural level in both experimental groups. It is concluded that the deleterious effects on skeletal muscle are rather the common result of the alimentary restriction than the particular effect of amphetamine.