The main musculature present in adult male Schistosoma
mansoni is mainly of the smooth muscle type. As we have previously
demonstrated, the contraction of S. mansoni presents a
tonic component, dependent on extraworm calcium, and a phasic one,
dependent on intracellular/intraworm calcium. Since intracellular
calcium channels sensitive to the alkaloid ryanodine and therefore
known as ryanodine receptors (RyR) have been demonstrated in a variety
of mammalian as well as non-mammalian (chicken, frog) and
non-vertebrate cells (Caenorhabditis elegans, lobster and
drosophila), the main objective of this work was to investigate the
presence of RyR in S. mansoni, as well as their subcellular
distribution profile, pharmacological modulation and their putative
involvement in S. mansoni contractility.
