ATP and [3H]noradrenaline release and the presence of ecto-Ca(2+)-ATPases in the capsule-glomerulosa fraction of the rat adrenal gland.
Both [3H]noradrenaline ([3H]NA) and ATP were released in response to supramaximal electric field stimulation in superfused rat adrenal capsule-glomerulosa preparations. The voltage-dependent potassium channel blocker 4-aminopyridine enhanced, while the ATP-sensitive potassium channel blocker glibenclamide failed to affect the stimulation-evoked release of [3H]NA. The selective alpha 2-adrenoceptor antagonist CH-38083 enhanced the evoked release of [3H]NA while the P2 receptor agonist ATP and alpha, beta-methylene-ATP failed to affect it. Neither the adenosine A1 receptor agonist N6-cyclopentyl-adenosine (CPA) nor the adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) influenced the stimulation-evoked [3H]NA release. The data showed that ATP was released from capsule-glomerulosa preparations in response to field stimulation together with but independently from [3H]NA, and that the local noradrenergic varicose axon terminals are not equipped with purinoceptors sensitive to ATP and/or adenosine. High concentrations of ATP also stimulated steroid hormone secretion in vitro, and thus may have a physiological role in this tissue. The presence of ecto-Ca(2+)-ATPases, enzymes able to terminate the effect of ATP, was demonstrated around the nerve profiles at the border of the capsule and zona glomerulosa tissue.
Jurányi
Z
Z
Institute of Experimental Medicine, Hungarian Academy of Sciences, Budapest, Hungary.
Orsó
E
E
Jánossy
A
A
Szalay
K S
KS
Sperlágh
B
B
Windisch
K
K
Vinson
G P
GP
Vizi
E S
ES
D015761:4-Aminopyridine / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000378:metabolism* / Q000494:pharmacology; D000311:Adrenal Glands / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D001599:Berberine / Q000031:analogs & derivatives / Q000494:pharmacology; D000252:Calcium-Transporting ATPases / Q000032:analysis / Q000378:metabolism*; D004558:Electric Stimulation; D005905:Glyburide / Q000494:pharmacology; D006651:Histocytochemistry; D008297:Male; D008854:Microscopy, Electron; D009638:Norepinephrine / Q000378:metabolism*; D009924:Organ Culture Techniques; D026902:Potassium Channel Blockers; D051381:Rats; D017208:Rats, Wistar; D013779:Tetrodotoxin / Q000494:pharmacology; D014316:Tritium
D000317:Adrenergic alpha-Antagonists; D026902:Potassium Channel Blockers; D001599:Berberine; D014316:Tritium; C048886:7,8-(methylenedioxy)-14-hydroxyberbane; D013779:Tetrodotoxin; D000255:Adenosine Triphosphate; D015761:4-Aminopyridine; D000252:Calcium-Transporting ATPases; D005905:Glyburide; D009638:Norepinephrine