Faculty Collaboration Database

Neuronal nitric oxide synthase inhibition prevents cerebral palsy following hypoxia-ischemia in fetal rabbits: comparison between JI-8 and 7-nitroindazole. Dev Neurosci 2011;33(3-4):312-9

Date

06/11/2011

Pubmed ID

21659718

Pubmed Central ID

PMC3225251

DOI

10.1159/000327244

Scopus ID

2-s2.0-80255131292 (requires institutional sign-in at Scopus site)   38 Citations

Abstract

Cerebral palsy and death are serious consequences of perinatal hypoxia-ischemia (HI). Important concepts can now be tested using an animal model of cerebral palsy. We have previously shown that reactive oxygen and nitrogen species are produced in antenatal HI. A novel class of neuronal nitric oxide synthase (nNOS) inhibitors have been designed, and they ameliorate postnatal motor deficits when administered prior to the hypoxic-ischemic insult. This study asks how the new class of inhibitors, using JI-8 (K(i) for nNOS: 0.014 μM) as a representative, compare with the frequently used nNOS inhibitor 7-nitroindazole (7-NI; K(i): 0.09 ± 0.024 μM). A theoretical dose equivalent to 75 K(i) of JI-8 or equimolar 7-NI was administered to pregnant rabbit dams 30 min prior to and immediately after 40 min of uterine ischemia at 22 days gestation (70% term). JI-8 treatment resulted in a significant decrease in NOS activity (39%) in fetal brain homogenates acutely after HI, without affecting maternal blood pressure and heart rate. JI-8 treatment resulted in 33 normal kits, 2 moderately and 13 severely affected kits and 5 stillbirths, compared with 8 normal, 3 moderately affected and 5 severely affected kits and 10 stillbirths in the 7-NI group. In terms of neurobehavioral outcome, 7-NI was not different from saline treatment, while JI-8 was superior to saline and 7-NI in its protective effect (p < 0.05). In the surviving kits, JI-8 significantly improved the locomotion score over both saline and 7-NI scores. JI-8 was also significantly superior to saline in preserving smell, muscle tone and righting reflex function, but 7-NI did not show significant improvement. Furthermore, a 100-fold increase in the dose (15.75 μmol/kg) of 7-NI significantly decreased systolic blood pressure in the dam, while JI-8 did not. The new class of inhibitors such as JI-8 shows promise in the prevention of cerebral palsy and is superior to the previously more commonly used nNOS inhibitor.

Author List

Yu L, Derrick M, Ji H, Silverman RB, Whitsett J, Vásquez-Vivar J, Tan S

Author

Jeannette M. Vasquez-Vivar PhD Professor in the Biophysics department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Animals, Newborn
Cerebral Palsy
Enzyme Inhibitors
Female
Fetus
Humans
Hypoxia-Ischemia, Brain
Indazoles
Neuropsychological Tests
Nitric Oxide Synthase Type I
Pregnancy
Rabbits