passages.id: split_1_test_1519_passage
passages.type: progene_text
passages.text: Both type 1 and type 2A isoforms were absent in muscles regenerated during tetrodotoxin ( TTX ) block of impulse conduction in the sciatic nerve , but type 2A was still present when the TTX block was associated with the vinblastine block of axoplasmic flow ; vinblastine block alone caused the coexpression of type 1 and type 2A isoforms in the majority of fibers .