Biomaterial Database

Effects of neuropeptide Y (NPY) on isolated guinea-pig heart. 1987

C Wahlestedt, and B Wohlfart, and R Håkanson

Neuropeptide Y (NPY) is present in nerve fibres throughout the mammalian heart. We have elucidated the effects of NPY on the isolated papillary muscle and heart (Langendorff) from the guinea-pig. The paced papillary muscle was studied with regard to duration of the action potential, peak force, maximum rate of force development, time to peak force, and time from peak force to half relaxation; all these parameters were identical whether or not NPY (5 X 10(-7) M) was present in the medium. When a stimulation with trains of pulses was superimposed, the paced papillary muscle exhibited enhanced contractions. This increase in contractility was not observed in the presence of the beta-adrenoceptor antagonist propranolol (10(-6) M) and was thus considered to be adrenergically mediated. The latter (adrenergic) response was markedly attenuated by NPY. Since NPY did not interfere with the response to exogenous noradrenaline (NA) it is suggested that the peptide exerts a pre-junctional inhibitory affect on adrenergic nerve-mediated positive inotropy. Neuropeptide Y did not influence the electrocardiogram from the spontaneously beating heart (Lagendorff), nor did the peptide modify the positive chronotropic effect of exogenously applied NA. In conclusion, the results indicate that NPY is without effect on the heart muscle proper but that the sympathetic terminals of the heart possess pre-junctional receptors for NPY (and/or related peptides) related to suppression of stimulated NA release.

UI	MeSH Term	Description	Entries
D009119	Muscle Contraction	A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.	Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D009200	Myocardial Contraction	Contractile activity of the MYOCARDIUM.	Heart Contractility,Inotropism, Cardiac,Cardiac Inotropism,Cardiac Inotropisms,Contractilities, Heart,Contractility, Heart,Contraction, Myocardial,Contractions, Myocardial,Heart Contractilities,Inotropisms, Cardiac,Myocardial Contractions
D009478	Neuropeptide Y	A 36-amino acid peptide present in many organs and in many sympathetic noradrenergic neurons. It has vasoconstrictor and natriuretic activity and regulates local blood flow, glandular secretion, and smooth muscle activity. The peptide also stimulates feeding and drinking behavior and influences secretion of pituitary hormones.	Neuropeptide Y-Like Immunoreactive Peptide,Neuropeptide Tyrosine,Neuropeptide Y Like Immunoreactive Peptide,Tyrosine, Neuropeptide
D010210	Papillary Muscles	Conical muscular projections from the walls of the cardiac ventricles, attached to the cusps of the atrioventricular valves by the chordae tendineae.	Muscle, Papillary,Muscles, Papillary,Papillary Muscle
D011433	Propranolol	A widely used non-cardioselective beta-adrenergic antagonist. Propranolol has been used for MYOCARDIAL INFARCTION; ARRHYTHMIA; ANGINA PECTORIS; HYPERTENSION; HYPERTHYROIDISM; MIGRAINE; PHEOCHROMOCYTOMA; and ANXIETY but adverse effects instigate replacement by newer drugs.	Dexpropranolol,AY-20694,Anaprilin,Anapriline,Avlocardyl,Betadren,Dociton,Inderal,Obsidan,Obzidan,Propanolol,Propranolol Hydrochloride,Rexigen,AY 20694,AY20694,Hydrochloride, Propranolol
D006168	Guinea Pigs	A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.	Cavia,Cavia porcellus,Guinea Pig,Pig, Guinea,Pigs, Guinea
D006321	Heart	The hollow, muscular organ that maintains the circulation of the blood.	Hearts
D000200	Action Potentials	Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.	Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In