Cerebral cortex 29 anesthesia

Biological Activities and Analogues. Somatostatin exerts some neurotropic actions, eg, as a tranquilizer and as a spontaneous motor activity depressor. It also lengthens barbiturate anesthesia time and induces sedation and hypothermia. These actions are consistent with the strong association between somatostatin and GABA in the primate cerebral cortex, 90—95% of somatostatin-positive ceHs also contain GABA (100). 

Albrecht J, Hilgier W, Zielinska M, Januszewski S, Hesselink M, et al. 2000. Extracellular concentrations of taurine, glutamate, and aspartate in the cerebral cortex of rats at the asymptomatic stage of thioacetamide-induced hepatic failure modulation by ketamine anesthesia. Neurochem Res 25(11) 1497-1502. 

The type of anesthesia can have a great effect on glucose use by the brain. In monkeys anesthetized with ketamine, F-FDG accumulation in the brain was 3.2 times greater than that in the conscious state and about 4.5 times greater in the cerebral cortex (Takashi Itoh, Osaka University, Japan). Under pentobarbital anesthesia, F-FDG accumulation in the occipital cortex was lower than when the animals were awake. The different effects of ketamine and pentobarbital are thought to be due to differences in hexokinase activity. 

The application of these alkaloids for clinical purposes is connected with the induction of general anesthesia. Clinical consideration should be paid to the fact that these alkaloids also affect the brain and thereby the central nervous system. Atropine crosses the blood-brain barrier. Hyoscyamine and hyosca-mine depress the motor areas of the cerebral cortex. 

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