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.
The neurotransmitter then crosses the synaptic gap to reach the receptor site of the other cell or neuron. Then, in a process known as reuptake, the neurotransmitter attaches to the receptor site and is reabsorbed by the neuron. Neurotransmitters play a major role in everyday life and functioning. Scientists do not yet know exactly how many neurotransmitters exist, but more than 100 chemical messengers have been identified.