Neuroprotective efficacy of subcutaneous insulin-like growth factor-I administration in normotensive and hypertensive rats with an ischemic stroke.

Abstract

The aim of this study was to test the insulin-like growth factor-I (IGF-I) as a neuroprotective agent in a rat model for ischemic stroke and to compare its neuroprotective effects in conscious normotensive and spontaneously hypertensive rats. The effects of subcutaneous IGF-I injection were investigated in both rat strains using the endothelin-1 rat model for ischemic stroke. Motor-sensory functions were measured using the Neurological Deficit Score. Infarct size was assessed by Cresyl Violet staining. Subcutaneous administration of IGF-I resulted in significantly reduced infarct volumes and an increase in motor-sensory functions in normotensive rats. In these rats, IGF-I did not modulate blood flow in the striatum and had no effect on the activation of astrocytes as assessed by GFAP staining. In hypertensive rats, the protective effects of IGF-I were smaller and not always significant. Furthermore, IGF-I significantly reduced microglial activation in the cortex of hypertensive rats, but not in normotensive rats. More detailed studies are required to find out whether the reduction by IGF-I of microglial activation contributes to an impairment IGF-I treatment efficacy. Indeed, we have shown before that microglia in hypertensive rats have different properties compared to those in control rats, as they exhibit a reduced responsiveness to ischemic stroke and lipopolysaccharide.

DOI: 10.1016/j.neuroscience.2013.07.016

Cite this paper

@article{Geyter2013NeuroprotectiveEO, title={Neuroprotective efficacy of subcutaneous insulin-like growth factor-I administration in normotensive and hypertensive rats with an ischemic stroke.}, author={Deborah De Geyter and Wendy Stoop and Sophie Sarre and Jacques H A De Keyser and R. Kooijman}, journal={Neuroscience}, year={2013}, volume={250}, pages={253-62} }