Modulation of Alpha2-Adrenergic Receptors of Rat Vas Deferens by Adenosine Receptors
It is generally considered that norepinephrine and ATP are co-stored in dense core vesicles in the sympathetic nerve terminals (1,2) and that the two substances are released together on stimulation (3–5). Furthermore, it was reported that the response of vas deferens induced by norepinephrine was augmented by adenosine (6). Adenosine in the synaptic cleft comes from ATP in the nerve terminals and also from the smooth muscles. We examined the effects of adenosine and its derivatives on adrenergic receptors in rat vas deferens and found that adenosine and its derivatives have a novel effect on presynaptic adrenergic α2 receptors through activation of adenosine receptors.
KeywordsAdenosine Receptor Contractile Response Vasoactive Intestinal Polypeptide Dense Core Vesicle Sympathetic Nerve Terminal
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