Innervation and maturation of muscular tissue in testicular teratomas in strain 129/Sv-ter mice.
In strain 129/Sv-ter mice, teratomas develop spontaneously during the 13th day of gestation. These testicular germ cell tumors exhibit characteristics of different germ layers closely resembling normal embryonic tissue. We investigated the interrelationship between nervous and muscular tissues (often found side by side) in teratomas of 4-week-old 129/Sv-ter mice. In well-differentiated mouse teratomas, histochemically and immunohistochemically distinct muscle fiber types could be distinguished, but not with all reactions. According to its aerobic oxidative capacity, teratoma muscle tissue was comparable with normal muscles. However, with respect to myosin-related properties, fiber type differentiation was incomplete. The muscle fibers - generally arranged in bundles - contained one centrally located endplate which was contacted mostly by a single nerve terminal. From this, proper endplate zones within the fiber bundles were formed. Occasionally "type grouping" was encountered, suggesting collateral axonal branching paralleled by synapse elimination. Together with the earlier in vivo observation of muscular contractions, we assume that teratoma muscle fibers are innervated by nerve cells (within the nervous tissue compartments) corresponding to spinal motoneurons. Thus, myogenesis, maturation and innervation of skeletal muscular tissue in mouse teratomas are largely comparable to normal development.
Müntener
M
M
Institute of Anatomy, University of Zürich-Irchel, Switzerland.
Kägi
U
U
Stevens
L C
LC
Walt
H
H
D000818:Animals; D006651:Histocytochemistry; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D009132:Muscles / Q000737:chemistry / Q000294:innervation / Q000473:pathology; D013724:Teratoma / Q000737:chemistry / Q000473:pathology*; D013736:Testicular Neoplasms / Q000737:chemistry / Q000473:pathology*