A process in which membrane potential cycles through a depolarizing spike, triggered in response to depolarization above some threshold, followed by repolarization. This cycle is driven by the flow of ions through various voltage gated channels with different thresholds and ion specificities.

Any process that modulates the frequency or rate of heart contraction.

Any process that increases the concentration of calcium ions in the cytosol.

The vesicular release of classical neurotransmitter molecules from a presynapse, across a chemical synapse, the subsequent activation of neurotransmitter receptors at the postsynapse of a target cell (neuron, muscle, or secretory cell) and the effects of this activation on the postsynaptic membrane potential and ionic composition of the postsynaptic cytosol. This process encompasses both spontaneous and evoked release of neurotransmitter and all parts of synaptic vesicle exocytosis. Evoked transmission starts with the arrival of an action potential at the presynapse.

Any process that results in a change in state or activity of a cell or an organism (in terms of movement, secretion, enzyme production, gene expression, etc.) as a result of a nickel cation stimulus.

A process in which force is generated within smooth muscle tissue, resulting in a change in muscle geometry. This process occurs in the artery. Force generation involves a chemo-mechanical energy conversion step that is carried out by the actin/myosin complex activity, which generates force through ATP hydrolysis. The artery is a vessel carrying blood away from the heart.

Any process that modulates the establishment or extent of a membrane potential, the electric potential existing across any membrane arising from charges in the membrane itself and from the charges present in the media on either side of the membrane.

Any process that activates or increases the frequency, rate or extent of calcium ion-dependent exocytosis.

Any process that modulates the frequency, rate or extent of the directed movement of calcium ions into, out of or within a cell, or between cells, by means of some agent such as a transporter or pore.

Any process that modulates the establishment or extent of a membrane potential in the depolarizing direction away from the resting potential in an atrial cardiomyocyte.

The directed movement of calcium ions (Ca2+) into the cytosol.

The directed movement of calcium ions into a cell or organelle.

A process in which a calcium ion is transported from one side of a membrane to the other by means of some agent such as a transporter or pore.

All of the contents of a cell excluding the plasma membrane and nucleus, but including other subcellular structures.

The membrane surrounding a cell that separates the cell from its external environment. It consists of a phospholipid bilayer and associated proteins.

The membrane surrounding a cell that separates the cell from its external environment. It consists of a phospholipid bilayer and associated proteins.

A lipid bilayer along with all the proteins and protein complexes embedded in it an attached to it.

A neuron projection that has a short, tapering, morphology. Dendrites receive and integrate signals from other neurons or from sensory stimuli, and conduct nerve impulses towards the axon or the cell body. In most neurons, the impulse is conveyed from dendrites to axon via the cell body, but in some types of unipolar neuron, the impulse does not travel via the cell body.

The portion of a neuron that includes the nucleus, but excludes cell projections such as axons and dendrites.

The portion of a cell bearing surface projections such as axons, dendrites, cilia, or flagella that includes the nucleus, but excludes all cell projections.

Cytoplasm situated near, or occurring around, the nucleus.