Some morphological effects of strychnine on the spinal cord: A light and electron microscopic study


  • This research supported in part by Anatomy Training Grant 5 T1 495-04; USPHS Grant NB-00690-1OS1 and USPHS Grant AM-08222-01


Adult rats, given intracardiac injections of strychnine (2.5 mg/kg), were allowed to convulse for periods of 5 or 35 minutes after which they were perfused with osmium tetroxide using a variation of Palay's method.

Light and electron microscopic examinations revealed no discernible changes in the size of the soma or appearance of the nuclei or nucleoli of the neurons of the ventral horn. However, light microscopic studies showed that clustering of the basophilic content was not as well defined as in the control cells. The most conspicuous feature of the treated material was the presence of a peripheral network of clear spaces in the cytoplasm of many of the large neurons.

An electron microscopic investigation showed that many neurons exhibited obvious and consistent cytoplasmic differences from control cells. These differences consisted of dilated endoplasmic spaces approximately 0.4 μ in diameter dispersed throughout the cytoplasm and devoid of material of appreciable density. The Golgi complex was more conspicuous and vesicles surrounding the complex appeared to be more numerous following the convulsive periods. These cytological changes were more extensive and prominent after 35 minutes than after five minutes. Mitochondria were comparable in appearance to those of control cells and vesicles of the axosomatic and axodendritic endings did not seem to differ structurally or numerically from those of control tissues.