Constitutive and inducible nitric oxide synthase activities after spinal cord contusion in rats.
Nitric oxide (NO) plays a role in the secondary damage after spinal cord (SC) injury. NO is produced by the activity of two classes of enzymes: calcium-dependent constitutive nitric oxide synthase (NOS) and calcium-independent inducible NOS. To determine the time course of both NOS activities after SC injury, 50 Wistar rats were submitted to severe SC contusion. NOS activities were assayed at the site of SC injury at several times after lesion. Results showed a significant increase of 138 and 96% in the constitutive NOS activity at 4 and 8 h after the lesion, respectively, as compared to sham-operated rats. iNOS activity was increased 72 h after lesion by 103% (P<0.05). In conclusion, both isoforms of NOS increase their activity at different time periods after SC injury.
Díaz-Ruiz
Araceli
A
Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suarez, Mexico City DF, Mexico.
Ibarra
Antonio
A
Pérez-Severiano
Francisca
F
Guízar-Sahagún
Gabriel
G
Grijalva
Israel
I
Ríos
Camilo
C
D000818:Animals; D003288:Contusions / Q000201:enzymology*; D005260:Female; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D051381:Rats; D017208:Rats, Wistar; D013116:Spinal Cord / Q000201:enzymology*; D013119:Spinal Cord Injuries / Q000201:enzymology*; D013997:Time Factors
D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C496322:Nos1 protein, rat; C496318:Nos2 protein, rat; C496316:Nos3 protein, rat