Acetylcholine is released from a presynaptic neuron into the synaptic cleft. Once in the synaptic gap, acetylcholine can: - Bind to presynaptic receptors: presynaptic activation or inhibition leads to automodulation of the presynaptic cholinergic neuron.
When welts are a sign of a medical problem, they are usually accompanied by other symptoms which provide clues to the problem. Physical trauma such as a blow can cause a welt, and welts can also be caused by allergic reactions, infections, injections, insect bites, and skin reactions, in very sensitive people. For example, in people with dermographism, even a gentle touch to the skin can cause a welt to emerge.
A welt is decorative piping around a cushion. A welt is a decorative ridge around a cushion, usually filled with a thin rope to help it keep its form. The welt may be made of the same fabric as the cushion, or a different fabric and color entirely for a decorative embellishment. Welts, by Any Name. Welts are also called piping and you'll see them on couch or chair cushions, floor cushions and throw pillows. This edging is created by sandwiching a thin rope in a narrow, long piece of fabric, folding the fabric in half around the roping, then stitching the fabric against the roping to create a tight sleeve around it.