Studies on the mechanism of inhibition of axoplasmic transport of neuronal organelles

Abstract

SummaryThis study is concerned with the effect of colchicine on the structure of fibrillar constituents of neurons and on the transport of neuronal organelles. Colchicine was injected beneath the perineurium of the hypoglossal nerve. Close to the site of the injection, the 24 and 48 h experimental axons showed loss of microtubules, increased numbers of filaments and increased amounts of the microfilamentous material bridging the filaments. Evidence of organelle damming was found proximal to the site of the injection. Five days after the injection of colchicine the nerves appear to have recovered and resemble control nerves. It is speculated that the circumscribed increase in the amount of filaments and microfilaments may produce a 'gel barrier' that interrupts mechanically the movement of organelles.

Peripheral nerve ischemia: Part 2. Accumulation of organelles

“…The most widely accepted explanation for organelle accumulation in damaged nerve is selective redistribution of axoplasmic organelles toward the lesion by normally occurring bidirectional axonal transport clear [ 17, 2 1,411. According to Rodriguez Echandia et al [36], the circumscribed increase in the quantity of filaments and microfilaments in colchicine-induced lesions is thought to produce a mechanical barrier that interrupts the movement of organelles. The mechanism of organelle accumulation in ischemic nerves seems to be quite different from that in crushed nerves or nerves exposed to vincristine or colchicine.…”