Normal expression and inflammation-induced changes of Na and Na/K ATPase activity in spinal dorsal horn of the rat.
We tested whether that peripheral inflammation induces changes in the spinal dorsal horn ATPase activity. Adult Sprague-Dawley rats were anesthetized (thiobarbital), the left hind paw (inflammation group; n = 15) was immersed in water at 60 degrees C for 60s, which induced a local inflammation. A control group (n = 12) was tested with water at room temperature. After 60 min of peripheral inflammation left (LDH) or right lumbar dorsal horn (RDH) were processed for total, Na/K, Na and remanent ATPase activities (nM P(i) (mgprotein)(-1) min(-1)). In control animals isoenzymatic activities were: Na (31.2%); Na/K (20.6%) and remanent (48.2%) from total ATPase activity. No LDH-RDH asymmetry was found. The inflammation group presented an ipsilateral increase of total ATPase activity in LDH (X+/-S.E.M.; 4798.9+/-601) over the RDH (3982.2+/-451; Delta+817; P<0.05). This is due to an increase in Na ATPase activity (1609.3+/-297) over RDH (1164.2+/-166; Delta+445; P<0.05). ATPase activities were increased in LDH from inflamed over the control group as follows: total (4798.9+/-601; Delta+840; P<0.05), Na/K (1298.1+/-301; Delta+483; P<0.05) and Na (1609.3+/-297; Delta+373; P<0.05). These increased ATPase activities, induced in a short time, can be considered a functional marker of nociceptive neuronal activity.
Czaplinski
Mariana
M
Dpto. de Ciencias Fisiológicas, Facultad de Ciencias de la Salud, Universidad de Carabobo, P.O. Box 3798, El Trigal 2002, Valencia, Venezuela.
Abad
Cilia
C
Eblen-Zajjur
Antonio
A
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000818:Animals; D027682:Cation Transport Proteins / Q000378:metabolism*; D007839:Functional Laterality / Q000502:physiology; D006358:Hot Temperature / Q000009:adverse effects; D007249:Inflammation / Q000209:etiology / Q000378:metabolism*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013126:Spinal Nerve Roots / Q000201:enzymology* / Q000378:metabolism*
D027682:Cation Transport Proteins; D000251:Adenosine Triphosphatases; C021838:sodium-translocating ATPase; D000254:Sodium-Potassium-Exchanging ATPase