Early changes in nitric oxide synthase activity in atrial intramural arteries following experimental spinal cord injury in rats.
Previously, we have shown that immediately after an experimental spinal cord injury (SCI) in anaesthetized rats, there is a large fall in mean arterial pressure (MAP) and heart rate (HR), followed by an abrupt increase in MAP. To evaluate the participation of nitric oxide (NO), we evaluated the activity of nitric oxide synthase (NOS) using Nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase histochemistry in sections of atria at several post-injury time-intervals. Staining increased at 3 min, reached a maximum at 9 min and diminished 30 min after injury. Pretreatment with atropine prevented changes in MAP, HR and NADPH-d staining suggesting that such modifications result from an increased vagal stimulation. In conclusion, the NOS activity is transiently elevated in the atrial intramural arteries of rats subjected to an SCI.
Bravo
G
G
Depto. Farmacología y Toxixología, México D.F., Mexico. gbravof@dfl.telmex.net.mx
Larios
F
F
Rojas-Martínez
R
R
Hong
E
E
Salazar
L A
LA
Guízar-Sahagún
G
G
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects; D003331:Coronary Vessels / Q000201:enzymology* / Q000473:pathology; D008058:Dihydrolipoamide Dehydrogenase / Q000378:metabolism; D006325:Heart Atria; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D019001:Nitric Oxide Synthase / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013119:Spinal Cord Injuries / Q000201:enzymology* / Q000503:physiopathology; D013997:Time Factors
D001285:Atropine; D019001:Nitric Oxide Synthase; D008058:Dihydrolipoamide Dehydrogenase