Premium
Modulation of cholinergic neurotransmission in guinea‐pig trachea by neuropeptide Y
Author(s) -
Stretton C.D.,
Barnes P.J.
Publication year - 1988
Publication title -
british journal of pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.432
H-Index - 211
eISSN - 1476-5381
pISSN - 0007-1188
DOI - 10.1111/j.1476-5381.1988.tb10325.x
Subject(s) - cholinergic , endocrinology , medicine , neuropeptide y receptor , acetylcholine , adrenergic , bretylium , yohimbine , guinea pig , neurotransmission , neurotransmitter , stimulation , inhibitory postsynaptic potential , neuropeptide , chemistry , biology , receptor , central nervous system , antagonist
1 Neuropeptide Y (NPY) is localized to adrenergic nerves in guinea‐pig airways but its function is not known. 2 NPY (1 × 10 −10 ‐3 × 10 −7 m ) had no direct effect on guinea‐pig tracheal smooth muscle in vitro.3 NPY produced a concentration‐ and frequency‐dependent inhibition of the cholinergic component of responses elicited by electrical field stimulation (EFS) whilst having no effect on the contractile response to exogenously applied acetylcholine (ACh). 4 Yohimbine was able to reverse significantly the inhibitory effect of noradrenaline on the cholinergic component to EFS without having any significant effect on the inhibition produced by NPY. 5 Neither blockade of β‐adrenoceptors by propranolol, nor depletion of adrenergic nerves by incubation with 6‐hydroxydopamine caused any significant alteration in the response to EFS in the presence of 3 × 10 −7 m NPY. Bretylium tosylate incubation to prevent noradrenaline release produced a small but significant enhancement of the inhibitory effect of NPY on EFS at high frequencies. 6 NPY appears to reduce the cholinergic component to EFS via a prejunctional mechanism, acting directly on receptors on cholinergic nerve terminals, rather than affecting adrenergic mechanisms. NPY released by adrenergic nerves may modulate cholinergic neurotransmission in guinea‐pig airways.