Also Known As:spastic
Mice homozygous for the spastic spontaneous mutation (Glrbspa) can usually be recognized at 14 days of age, but some mutant mice may not be reliably distinguished until 5 or 6 weeks of age. They show spastic symptoms in response to handling, but spastic behavior can occur spontaneously. The spasms consist of rapid tremor, stiffness of posture, and difficulty in righting when placed on the back. No anatomical pathology occurs in either muscle or the central nervous system, except that herniated intervertebral discs and cysts of the leptomeninges occur, most severely in the lumbar region, possibly resulting from traumatic injuries sustained during the myoclonic episodes. The spastic symptoms can be markedly alleviated by intraperitoneal injection of aminooxyacetic acid, an inhibitor of g-aminobutyric acid transaminase (GABA-T), but not by Dilantin or trimethadione. Glycine receptor expression in the CNS of spastic mice is reduced to 20%, or less, of normal.
