Central nervous system response

TABLE 67-2. Central Nervous System Response to Infection (Cerebrospinal Fluid Findings)4,15 24... 

Testing of the subjects consisted of both subjective evaluations and physiological and central nervous system responses observed under medical supervision. The lowest concentration at which odor was detected was 0.2 ppm (four of nine subjects), but the ability to detect the odor disappeared within 5 min. Subjective symptoms consisted of headache and eye irritation. At 0.1 ppm, two of the subjects experienced mild headache (Table 2-3). One of these subjects had developed headache during each of the control exposures and during the exposure at 0.03 ppm. The other subject developed headache after 6 h, and the headache continued for several hours postexposure. 

A9-Tetrahydrocannabinol (A9-THC) is considered to be the predominant compound in preparations of C. sativa (marijuana, hashish, bhang) that is responsible for the central nervous system effects in humans. The recognized central nervous system responses to these preparations include alterations in cognition and memory, euphoria, and sedation. Potential therapeutic applications of cannabis preparations that are of either historical or contemporary interest include analgesia, attenuation of the nausea and vomiting of cancer chemotherapy, appetite stimulation, decreased intestinal motility of diarrhea, decreased bronchial constriction of asthma, decreased intraocular pressure of glaucoma, antirheumatic and antipyretic actions, and treatment of convulsant disorders. These effects have been reviewed recently (Howlett, 1995). 

The first identified cannabinoid receptor subtype, CB was cloned and demonstrated to have an amino acid sequence consistent with a tertiary structure typical of the seven transmembrane-spanning proteins that are coupled to G proteins. In addition to being found in the central nervous system, mRNA for CB has also been identified in testes. The central nervous system responses to cannabinoid compounds are believed to be mediated exclusively by CB, inasmuch as CB2 transcripts could not be found in brain tissue by either Northern analysis or in situ hybridization studies. CBj transduces signals in response to central-nervous-system-active constituents of C. sativa as well as synthetic bicyclic and tricyclic cannabinoid analogs, aminoalkylindole, and eicosanoid cannabimimetic compounds. CB is coupled to G, to inhibit adenylate cyclase activity and to a pertussis-sensitive G protein to regulate Ca2+ currents. 

Ephedra supplements typically contain caffeine, and users may consume caffeine in carbonated beverages, coffee, or tea. Researchers suspect that caffeine may enhance ephedra s stimulant effects on cardiovascular and/or central nervous system responses. This may account for the types of adverse events that have been reported by ephedra users. 

White JL, Darko DF, Brown SJ, Miller JC, Hayduk R, Kelly T, Mitler MM. Early central nervous system response to HIV infection sleep distortion and cognitive-motor decrements. AIDS 1995 9 1043-1050. 

Monlux WS, Luedke AJ, Browne J. Central nervous system response of horses to Venezuelan equine encephalomyelitis vaccine (TC-83). J Am Vet Med Assoc. 1972 161 (3) 265 269. 

Another important compound derived from tryptamine, 5-hydroxytryptamine (3) or serotonin, is derived by hydrox-ylation and is found in many plants (Fig. 28-5). Serotonin is widely distributed in nature and is a natural nerve transmitter in the central nervous system, responsible, at least in part, for sleep patterns. There also is some evidence that... 

A review is given of classic foreign body responses to polymeric drug delivery devices with emphasis on the central nervous system response. In vivo biocompatibility studies of implanted drug carriers are summarised to illustrate the behaviour of different classes of polymers and the methodologies used to evaluate their tolerance. 150 refs. 

Central Nervous System Response to Implanted Devices... 

Barbituric acid is the parent of a group of compounds known as barbiturates The bar biturates are classified as sedative-hypnotic agents meaning that they decrease the responsiveness of the central nervous system and promote sleep Thousands of deriva lives of the parent ring system of barbituric acid have been tested for sedative-hypnotic activity the most useful are the 5 5 disubstituted derivatives... 

Metabolic Functions. Manganese is essential for normal body stmcture, reproduction, normal functioning of the central nervous system, and activation of numerous enzymes (126). Synthesis of the mucopolysaccharide chondroitin sulfate involves a series of reactions where manganese is required in at least five steps (127). These reactions are responsible for formation of polysaccharides and linkage between the polysaccharide and proteins that form... 

Sedative. A drug that decreases responsiveness of the central nervous system. 

Ethanol is classified for medical purposes as a central nervous system (CNS) depressant. Its effects—that is, being drunk—resemble the human response to anesthetics. There is an initial excitability and increase in sociable behavior, but this results from depression of inhibition rather than from stimulation. At a blood alcohol concentration of 0.1% to 0.3%, motor coordination is affected, accompanied by loss of balance, slurred speech, and amnesia. When blood alcohol concentration rises to 0.3% to 0.4%, nausea and loss of consciousness occur. Above 0.6%, spontaneous respiration and cardiovascular regulation are affected, ultimately leading to death. The LD50 of ethanol is 10.6 g/kg (Chapter 1 Focus On). 

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