gamma-Aminobutyric acid in synovial membrane of rat knee joint.
gamma-Aminobutyric acid (GABA) content was measured, and the release of GABA was studied in the synovial membrane of the rat knee joint. GABA content of the synovial membrane was 20.1 nmol/g tissue. Ten days after unilateral dissection of the sciatic nerve, femoral nerve or both nerves, the GABA contents of the ipsilateral membrane were 13.8, 14.6 and 7.8 nmol/g tissue, respectively. High K+ evoked the Ca2+-dependent release of [3H] GABA from the synovial membranes of intact rats preloaded with [3H] GABA, but did not evoke release from the membrane ipsilateral to the dissection of both sciatic and femoral nerves. Evoked release of [3H] GABA was obtained in the synovial membrane preloaded with [3H] GABA in the presence of beta-alanine, but not in the presence of 2,4-L-diaminobutyric acid. These results indicate that GABA is present in the neuronal elements of the synovial membrane of the rat knee joint.
Nakano
A
A
Department of Orthopaedic Surgery, Kinki University School of Medicine, Osaka, Japan.
Kondo
M
M
Taniyama
K
K
Tanaka
S
S
D000818:Animals; D002118:Calcium / Q000502:physiology; D005260:Female; D007719:Knee Joint / Q000378:metabolism*; D008297:Male; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D012636:Secretory Rate / Q000187:drug effects; D013583:Synovial Membrane / Q000294:innervation / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D005680:gamma-Aminobutyric Acid; D011188:Potassium; D002118:Calcium