A REVIEW ON THE ROLE OF ANGIOTENSIN II IN THE SKELETAL MUSCLE HYPERTROPHY AND MUSCLE STRENGTH.

Angiotensin II (ANG II) is intensely involved in the hypertrophy of cardiac muscle cells. However, a potential role of ANG II in skeletal muscle hypertrophy has not been widely studied. The objective of the present review is to highlight the molecular mechanisms (if any) behind the role of ANG II in the regulation of the skeletal muscle growth. The available data (however limited) demonstrate that ANG II is necessary for an optimal overload-induced skeletal muscle hypertrophy. Although the exact mechanisms by which ANG II mediates skeletal muscle growth under conditions of overload remain unclear, these effects may be partly mediated by the type 1 receptor (ATI). Moreover, ANG II may influence hypertrophy via its interaction with the insulin-like growth factor I (IGF 1). Furthermore, it appears that circulating ACE (Angiotensin Converting Enzyme) activity is directly associated with human muscle strength. These findings support the assertion that ANG II is likely to act as a growth factor in human skeletal muscle. Identifying the optimal local concentration of ANG II needed to contribute to measurable skeletal muscle hypertrophy is of great importance. Discovering how ANG II may influence muscle hypertrophy /atrophy may lead to the development of new pharmacological interventions designed to increase muscle mass in cases when resistance training cannot be prescribed. Furthermore, finding alternative therapies to increase/preserve muscle mass would have a major impact on geriatric medicine, rehabilitation and sports science. [ABSTRACT FROM AUTHOR]