Adrenergic neuromodulation by endothelin in guinea pig pulmonary artery.
Endothelin was tested for possible interactions with the noradrenergic neuroeffector transmission in guinea pig pulmonary artery. Endothelin concentration-dependently enhanced nerve-induced contractile responses and concomitantly increased basal tone. Furthermore, endothelin inhibited the stimulation-evoked release of [3H]noradrenaline and enhanced the contractile response to exogenously applied noradrenaline. These results suggest that endothelin, in addition to its direct contractile effect, may function as a modulator of adrenergic neuroeffector transmission in the guinea pig pulmonary artery via both stimulatory post- and inhibitory prejunctional mechanisms.
Wiklund
N P
NP
Department of Physiology, Karolinska Institutet, Stockholm, Sweden.
Ohlén
A
A
Cederqvist
B
B
D000320:Adrenergic Fibers / Q000502:physiology*; D000818:Animals; D004558:Electric Stimulation; D016232:Endothelins; D005260:Female; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009638:Norepinephrine / Q000493:pharmacokinetics*; D010455:Peptides / Q000494:pharmacology*; D011651:Pulmonary Artery / Q000187:drug effects / Q000294:innervation / Q000502:physiology*; D014662:Vasoconstrictor Agents / Q000494:pharmacology*
D016232:Endothelins; D010455:Peptides; D014662:Vasoconstrictor Agents; D009638:Norepinephrine