Synapses+MC

-What is a motor neuron? It’s a nerve cell that conducts nerve impulses away from the central nervous system and innervates effectors (muscles and glands). Effectors carry out our responses to environmental changes, whether they are external or internal. -What is the name neurotransmitter released by motor neurons? Ach (acetylcholine). -How does botox prevent muscle contraction? It blocks the release of Ach into the synaptic cleft, and therefore muscle contraction never occurs. Botox is the trade name for botulinum toxin A, a neurotoxin produced by a bacterium. -What does cocaine interfere with at the synapses? Cocaine is a powerful stimulant in the CNS that interferes with the re-uptake of dopamine at synapse. The result is a rush of well-being that last 5-30 minutes. -What is the effect? Its extremely addictive and its use is very harmful. The result is sleeplessness, lack of appetite, increased sex drive, tremors, and “cocaine psychosis,” a condition that resembles paranoid schizophrenia. During the crash period, fatigue, depression, and irritability are common, along with memory loss and a confused state of cognition. -What neurotransmitter does meth resemble? It has a structure similar to that of dopamine, and it’s stimulatory effect mimics cocaine. - What is the effect? It reverses the effects of fatigue, maintains wakefulness, and temporarily elevates the mood of the user. After the initial rush, there is typically a state of high agitation that, in some individuals, leads to violent behavior. Chronic use can lead to what is called an amphetamine psychosis resulting in paranoia, auditory and visual hallucinations, self-absorption, irritability, and aggressive, erratic behavior. Drug tolerance, dependence, and addiction are common, and hyperthermia, convulsions, and death can occur. -Where is heroin derived? It is derived from the resin or sap of the opium poppy plant, which is grown from Turkey to Southeast Asia and in parts of Latin America. - What is heroin converted to that can bind opiate receptors in the brain? Heroin is the most abused opiate because it is rapidly delivered to the brain, where it is converted to morphine. Morphine binds promptly to opioid receptors, and the result is a rush sensation and euphoric experience. - What do the opiate receptors do? Opiates depress breathing, activate the reward circuit, block pain pathways, cloud mental function, and sometimes cause nausea and vomiting. -What is THC? It’s tetrahydrocannabinol in which the dried flowering tops, leaves, and stems of the Indian hemp plant Cannabis sativa contain and are covered by a resin that is rich in it, THC. - What is anandamide? It’s a neurotransmitter that belongs to a class of chemicals called cannaboids. - What is the relationship between THC and anandamide and cannabinoids? Both THC and anandamide belong to a class of chemicals called cannabinoids. It would seem, then, that THC mimics the actions of anadamide. - Why are the receptors that bind cannabinoids important? Receptors that bind cannabinoids are located in the hippocampus, cerebellum, basal ganglia, and cerebral cortex, brain areas that are important for memory, orientation, balance, motor coordination, and perception. - What does smoking THC cause? Mild euphoria, along with altercations in vision and judgment, occur. Distortions of space and time can also occur in occasional users. IN heavy users, hallucinations, anxiety, depression, rapid flow of ideas, body image distortions, paranoia, and psychotic symptoms can result.
 * Motor Neuron p.234
 * Cocaine p.268
 * Methamphetamine p.268
 * Heroin p. 268
 * Marijuana p. 269