The effects of iproniazid and reserpine on the accumulation of granular vesicles and noradrenaline in constricted adrenergic nerves.

1. The accumulation of granular vesicles proximal to a constriction applied to hypogastric nerves has been investigated with the electron microscope in cats treated with reserpine and/or iproniazid.2. The ultrastructural changes have been correlated with the accumulation of noradrenaline at the same site in similarly treated animals.3. The findings give further support to the view that granular vesicles constitute a major storage site for intraneuronal noradrenaline.