Pregnant women suffering from the common cold can be reassured about the safety of short-term use of OTC cold medications. These drugs, however, should not be used indiscriminately or for extended periods of time. In addition, use should be confined to only those products that are appropriate for the symptoms.
Acetylcholine (ACh) is a common neurotransmitter secreted by a variety of neurons. It binds to two different receptors-Ionotropic (fast) nicotinic receptors and metabotropic (slow) muscarinic receptors. 1  role in central nervous system. 2  role in peripheral nervous system. 3  receptors and signaling. 4  agonists and antagonists.
Neurotransmitters are endogenous chemicals that enable neurotransmission. They transmit signals across a chemical synapse, such as in a neuromuscular junction, from one neuron (nerve cell) to another target neuron, muscle cell, or gland cell. Enzyme degradation â special chemicals called enzymes break it down. 2  Reuptake â re-absorption of a neurotransmitter into the neuron. 3  Transporters, or membrane transport proteins, pump neurotransmitters from the synaptic cleft back into axon terminals (the presynaptic neuron) where they are stored.