Neuronal signalling expression profiles of motoneurons supplying multiply or singly innervated extraocular muscle fibres in monkey.

Motoneurons of the oculomotor nucleus subserving multiply innervated muscle fibres (MIF) receive different afferent inputs from the motoneurons subserving singly innervated muscle fibres (SIF). We asked whether MIF and SIF motoneurons have different neurotransmitter signalling expression profiles. Adult rhesus monkey extraocular muscles were injected with the retrograde tracer cholera toxin.