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Atrial natriuretic peptide (ANP) or atrial natriuretic factor (ANF) is a natriuretic peptide hormone secreted from the cardiac atria that in humans is encoded by the NPPA gene. [5] Natriuretic peptides (ANP, BNP , and CNP ) are a family of hormone/paracrine factors that are structurally related. [ 6 ]
A descent of 10 metres (33 feet) in water increases the ambient pressure by an amount approximately equal to the pressure of the atmosphere at sea level. So, a descent from the surface to 10 metres (33 feet) underwater results in a doubling of the pressure on the diver. This pressure change will reduce the volume of a gas filled space by half.
These cells produce an electrical impulse known as a cardiac action potential that travels through the electrical conduction system of the heart, causing it to contract. In a healthy heart, the SA node continuously produces action potentials, setting the rhythm of the heart (sinus rhythm), and so is known as the heart's natural pacemaker.
Electrocardiography is the process of producing an electrocardiogram (ECG or EKG [a]), a recording of the heart's electrical activity through repeated cardiac cycles. [4] It is an electrogram of the heart which is a graph of voltage versus time of the electrical activity of the heart [ 5 ] using electrodes placed on the skin.
4879 18158 Ensembl ENSG00000120937 ENSMUSG00000029019 UniProt P16860 P40753 RefSeq (mRNA) NM_002521 NM_001287348 NM_008726 RefSeq (protein) NP_002512 NP_002512 NP_001274277 NP_032752 Location (UCSC) Chr 1: 11.86 – 11.86 Mb Chr 4: 148.07 – 148.07 Mb PubMed search Wikidata View/Edit Human View/Edit Mouse Brain natriuretic peptide (BNP), also known as B-type natriuretic peptide, is a hormone ...
The process of depolarization is entirely dependent upon the intrinsic electrical nature of most cells. When a cell is at rest, the cell maintains what is known as a resting potential. The resting potential generated by nearly all cells results in the interior of the cell having a negative charge compared to the exterior of the cell.
In a whole, it is the heart's reaction to catecholamines (norepinephrine, epinephrine, dopamine). Conditions that decrease bathmotropy (i.e. hypercarbia) cause the heart to be less responsive to catecholaminergic drugs. A substance that has a bathmotropic effect is known as a bathmotrope.
An increase in sympathetic stimulation to the heart increases contractility and heart rate. An increase in contractility tends to increase stroke volume and thus a secondary increase in preload. An increase in preload results in an increased force of contraction by Starling's law of the heart; this does not require a change in contractility.