Does endogenous progesterone promote recovery of chronic sensorimotor deficits following contusion to the forelimb representation of the sensorimotor cortex?
We studied sensorimotor recovery in male, normal-cycling and pseudopregnant female rats following unilateral FL-SMC contusions. Forelimb use (push off before a rear, support against the walls, and landing after a rear) and the foot fault test (foot misplacements during locomotion on an elevated grid) were analyzed from videotapes taken before surgery, and then again on post-surgical days 2 and 36. High endogenous progesterone levels in females at the time of injury did not affect recovery as there were no differences between males, pseudopregnant females and normal-cycling female rats on these behaviors. None of the brain-injured rats recovered symmetrical forelimb use between 2 and 36 days after injury (P>0.05) and they also showed foot misplacements (P>0.05) in the foot fault test. Male and female rats with contusions had fewer mean foot misplacements on day 36 than 2 days after injury (P<0.001), indicating that there was partial recovery on this task. These results were taken to show that there were no sex differences in motor deficits caused by unilateral FL-SMC injury. In addition, higher endogenous progesterone levels in females did not protect them from the chronic sensorimotor deficits caused by unilateral FL-SMC contusions.
Grossman
K J
KJ
Department of Psychology, Emory University, 532 N. Kilgo Circle, Atlanta, GA 30322, USA. kgrossm@emory.edu
Stein
D G
DG
D000818:Animals; D001924:Brain Concussion / Q000503:physiopathology*; D001931:Brain Mapping; D005260:Female; D005552:Forelimb / Q000294:innervation*; D008297:Male; D009048:Motor Skills / Q000502:physiology; D009416:Nerve Regeneration / Q000502:physiology*; D009949:Orientation / Q000502:physiology; D011374:Progesterone / Q000502:physiology*; D011555:Pseudopregnancy / Q000503:physiopathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013003:Somatosensory Cortex / Q000293:injuries* / Q000503:physiopathology
D011374:Progesterone