Electronmicroscopic investigation of rat substantia nigra after chronic amphetamine treatment. I. Changes in the...

The neurones in substantia nigra of albino rats were studied at ultrastructural level after chronic intraperitoneal administration of dl-amphetamine (5 mg/kg) for 90 days. Neurones with proliferated cytoplasmic organelles (granulated and smooth endoplasmic reticulum) were observed, as well as a tendency towards increase in the number of dense core vesicles. Very often it was possible to observe neurones with disorganization of the cytoplasmic organelles, with drastic decrease and disappearance of the dense core vesicles and simultaneous rise in the number and hypertrophy of the complex vesicles. Although less frequently, there also occur profiles with increased electron density and swelling of the astroglial growths in the adjacent neuropile.