6533b829fe1ef96bd1289bc4

RESEARCH PRODUCT

Modulatory action of acetylcholine on cerebrovascular sympathetic neurotransmission

Cristina AlvarezEnrique AlborchJoséa. AlabadíFrancisco J. MirandaGermán TorregrosaJuan B. Salom

subject

medicine.medical_specialtySympathetic Nervous SystemContraction (grammar)Cerebral arteriesTyramineAdrenergicTetrodotoxinIn Vitro TechniquesSynaptic TransmissionMuscle Smooth VascularNorepinephrinechemistry.chemical_compoundIsometric ContractionInternal medicineMuscarinic acetylcholine receptormedicineAnimalsPharmacologyChemistryGoatsMuscarinic acetylcholine receptor M3Cerebral ArteriesTyramineAcetylcholineElectric StimulationAtropineEndocrinologyCerebrovascular CirculationFemaleAcetylcholinemedicine.drug

description

1. Acetylcholine (10 micrograms/min) diminished the electrically-induced cerebral blood flow reductions. Atropine (1-2 mg) partially blocked this inhibitory effect. 2. Exogenously administered noradrenaline (1-10 micrograms) and tyramine (50-500 micrograms) reduced cerebral blood flow but this effect was unchanged by acetylcholine infusion. 3. Acetylcholine inhibited the nonadrenergic component of the electrically-induced contraction at a concentration greater than or equal to 10(-6) M and potentiated the adrenergic component at a concentration greater than or equal to 10(5) M. Atropine 10(-7) M) inhibited both of these effects. In addition, acetylcholine (10(-4) M) enhanced the electrically-evoked [3H]noradrenaline overflow. 4. These results show that: (a) acetylcholine modulates cerebrovascular sympathetic neurotransmission by acting on muscarinic receptors; and (b) the potentiating effect of acetylcholine is achieved by a mechanism involving increases in noradrenaline release.

yearjournalcountryeditionlanguage
1991-01-01General Pharmacology: The Vascular System
https://doi.org/10.1016/0306-3623(91)90587-v