Organization of actin filaments in peritubular myoid cells from seminiferous tubule

LOSINNO A.D; MORALES A; LÓPEZ L.A

San Luis

Congreso; Reunión Científica conjunta de la Sociedad de Biología de Cuyo; 2011

Sociedad de Biología de Cuyo.

Myoid cells (MC) surround the seminiferous tubules (ST) and express contractile proteins of muscle cells like alfa-actin and myosin. Previous works showed an orthogonal display of actin filaments (AF) forming a net. In this study we analyzed the distribution of AF of MC by TEM and confocal microscopy. Isolated segments of ST from adult rats were fixed and hatched with alfa-actin-FITC antibody. On the other hand, segments of ST were processed by conventional technique for TEM study. Tangential confocal microscopy images of myoid cells showed that AF were distributed in two independent layers instead of an orthogonal net: the inner layer with filaments perpendicular to the ST axis and the external one with filaments parallel to the tubular axis. In both layers, filaments correspond with those of the neighboring cells. In addition, bundles of AF tighten these cells in the cell periphery. We confirmed this observation in cross sections of segments observed by TEM. The knowledge of the atypical distribution of AF and MF is very important to understand the role that myoid cells carry out in the contraction of the ST during spermatogenesis.