Emotional behaviors as well as the hippocampal reelin expression in C57BL/6N male mice chronically treated with corticosterone.

Depression is a common psychiatric disorder affecting around 300 million people worldwide. Serum cortisol and glucocorticoid levels in humans are reportedly higher in patients with depression compared to controls. Furthermore, rodents repeatedly treated with exogenous corticosterone (CORT), a glucocorticoid in rodents, exhibit deficits in emotional behaviors. To confirm the availability of mice with chronic CORT treatment as an animal model of depression, we investigated the effect of chronic CORT treatment on depression-like behavioral and neuropathological phenotypes in C57BL/6N male mice. Behavioral studies showed depression- and anxiety-like behaviors in mice treated with CORT compared with control mice in the forced-swim and elevated-plus maze tests. Additionally, treated mice represented anhedonia and social behavior impairments in the sucrose preference and social interaction tests, respectively. Brains of depression patients have altered expression of reelin, an extracellular matrix protein involved in neuronal development and function. Likewise, in the present study, mice with chronic CORT treatment also exhibited reelin downregulation in cells of the hippocampus. Hence, we investigated therapeutic effects of reelin supplementation on CORT-induced behavioral abnormalities in mice. Microinjections of recombinant reelin protein into the hippocampus did not rescue behavioral deficits in mice with chronic CORT treatment. These results suggest that C57BL/6N male mice chronically treated with CORT are a suitable animal depression model, in which depressive behaviors may occur independently of the alternation of hippocampal Reelin expression.

New surgical scoring system to predict postoperative mortality.

PURPOSE: There is still no easy and highly useful method to comprehensively assess both preoperative and intraoperative patient statuses to predict postoperative outcomes. We attempted to develop a new scoring system that would enable a comprehensive assessment of preoperative and intraoperative patient statuses instantly at the end of anesthesia, predicting postoperative mortality. METHODS: The study included 32,555 patients who underwent surgery under general or regional anesthesia from 2008 to 2012. From the anesthesia records, extracted factors, including patient characteristics and American Society of Anesthesiologists physical status classification (ASA-PS), and three intraoperative indexes (the lowest heart rate, lowest mean arterial pressure, and estimated volume of blood loss) are used to calculate the surgical Apgar score (sAs). The sAs and ASA-PS, and surgical Apgar score combined with American Society of Anesthesiologists physical status classification (SASA), which combines the sAs and ASA-PS into a single adjusted scale, were compared and analyzed with postoperative 30-day mortality. RESULTS: Increased severity of the sAs, ASA-PS and SASA was correlated with significantly higher mortality. The risk of death was elevated by 3.65 for every 2-point decrease in the sAs, by 6.4 for every 1-point increase in the ASA-PS, and by 9.56 for every 4-point decrease in the SASA. The ROC curves of the sAs and ASA-PS alone also individually demonstrated high validity (AUC = 0.81 for sAs and 0.79 for ASA-PS, P < 0.001). The SASA was even more valid (AUC = 0.87, P < 0.001). CONCLUSIONS: The sAs and ASA-PS were shown to be extremely useful for predicting 30-day mortality after surgery. An even higher predictive ability was demonstrated by the SASA, which combines these simple and effective scoring systems.

[Case of respiratory arrest during intraoperative magnetic resonance imaging (iMRI) for awake craniotomy].

We had a neurosurgical patient who developed apnea during iMRI. She was suspected of obstructive sleep apnea. The tumor had a risk of motor aphasia, and therefore awake craniotomy with iMRI was planned. First, the patient was anesthetized and her airway was secured. After 11 minutes of termination of anesthetics, the patient regained consciousness. The level of consciousness was sufficient. Her respiration was stable with oxygen supply. Anesthetics were not given any more. She gradually became drowsy when the tasks were finished and tumor was removed, although she responded to verbal commands. During the second iMRI, capnogram showed flat line and peripheral oxygen saturation level dropped to 90%. Scanning was urgently stopped and the patient was intubated. The patient recovered without any neurological deficits the day after the surgery although the reason of respiratory arrest is still unknown. Awake craniotomy could be challenging because of unsecured airway with risks of vomitting, epileptic attacks or unstable level of consciousness. It is considered that the patient monitoring becomes more difficult when iMRI is performed because the patient's face cannot be obsereved directly. We should remember that conscious level as well as respiration pattern may change during operation.

Sigma-1 receptor alters the kinetics of Kv1.3 voltage gated potassium channels but not the sensitivity to receptor ligands.

Sigma1 receptors (Sigma1R) are intracellular chaperone proteins that bind psychotropic drugs and also clinically used drugs such as ketamine and haloperidol. Co-expression of the Sigma1R has been reported to enhance the sensitivity of several voltage-gated ion channels to Sigma1R ligands. Kv1.3 is the predominant voltage-gated potassium channel expressed in T lymphocytes with a documented role in immune activation. To gain a better understanding of Sigma1R modulation of Kv ion channels, we investigated the effects of Sigma1R co-expression on Kv1.3 physiology and pharmacology in ion channels expressed in Xenopus oocytes. We also explored the protein domains of Kv1.3 necessary for protein:protein interaction between Kv1.3 and Sigma1R through co-immunoprecipitation studies. Slowly inactivating outward-going currents consistent with Kv1.3 expression were elicited on step depolarizations. The current characterized by E(rev), V(1/2), and slope factor remained unchanged when co-expressed with Sigma1R. Analysis of inactivation time constant revealed a faster Kv1.3 current decay when co-expressed with Sigma1R. However the sensitivity to Sigma1R ligands remained unaltered when co-expressed with the Sigma1R in contrast to the previously reported modulation of ligand sensitivity in closely related Kv1.4 and Kv1.5 voltage gated potassium channels. Co-immunoprecipitation assays of various Kv1.3 truncation constructs indicated that the transmembrane domain of the Kv1.3 protein was responsible for the protein:protein interaction with the Sigma1R. Sigma1R likely interacts with different domains of Kv ion channel family proteins resulting in distinct modulation of different channels.

[Can preoperative administration of H2 blocker reduce the incidence of postoperative nausea and vomiting (PONV)?].

BACKGROUND: PONV is a complication that reduces a patient's quality of life (QOL). Recently, it was reported that PONV is reduced by preoperative administration of histamine receptor (H1 and H2) inhibitor. In the present study, based on the hypothesis that PONV might be reduced by preoperative administration of H2 blocker, we examined the effect of preoperative administration of H2 blocker only on the incidence of PONV. METHODS: Eighty seven patients having regular operations were randomly assigned into two groups; the control (C), and the H2 blocker (F) groups. In the operating room, 20 min after intravenous injection of famotidine 20 mg as H2 blocker, anesthesia was maintened by sevofluorane, oxygen, nitrous oxide, and fentanyl following the induction by fentanyl, propofol, and vecuronium. The frequency and extent of vomiting were observed and the patients were interviewed at postoperative hours 0-6 and 6-12. The incidences between the two groups were examined using the chi-squared test. RESULTS: No significant difference in the appearance of PONV was found between the F group and the C group. In women in the F group, the incidence of vomiting was lower. CONCLUSIONS: Preoperative administration of H2 blocker tends to reduce PONV in women.

[Urine specific gravity during general anesthesia].

BACKGROUND: The urine volume and urine specific gravity per unit time during a short operation under volume loading were examined to explore the possibility of urine specific gravity as an indirect index of fluid therapy. METHODS: After introducing anesthesia, under volume loading with acetic acid Ringer solution 10 ml x kg(-1) x hr(-1), urine volume and specific gravity per unit time at 30 min intervals from urination to 90 min later and the correlation between the urine volume and urine specific gravity were examined. A chronological increase of urine specific gravity was also confirmed. Therefore, the values of urine specific gravity of each 30 minute intervals were compared using Student's t-test. RESULTS: The urine volume and urine specific gravity per unit time showed no significant negative correlation until after 90 min. Increasing urine specific gravity even under volume loading became significant 90 min after urination. CONCLUSIONS: There is a possibility of employing urine specific gravity as an indirect index of fluid therapy.

[The injection pain of propofol with different emulsion].

BACKGROUND: Incidence and intensity of pain on intravenous injection of propofol were assessed with emulsion of long-chain/medium-chain triglycerides (LCT/MCT, 50: 50) and only long-chain triglycerides (LCT, 100) in patients undergoing different elective surgical interventions in this prospective, randomized, cross over and double-blinded study. METHODS: 1) Forty six patients were assigned to two groups. One group received 0.2 mg x kg(-1) LCT/ MCT propofol prior to LCT propofol administration. The other group received 0.2 mg x kg(-1) LCT propofol prior to LCT/MCT propofol administration. Pain elicited upon questioning was assessed with each injection in the two groups. Patients were asked to grade the pain as VAS of 0 to 100 mm. 2) Fifty one patients were randomly assigned to two groups. One group received 0.4 mg x kg(-1) LCT propofol. The other group received 0.4 mg x kg(-1) LCT/MCT propofol. Patients were asked to grade the pain as VAS of 0 to 100 mm. RESULTS: Pain of LCT propofol injection was stronger than LCT/MCT propofol. As incidence of 0.4 mg x kg(-1) propofol injection, VAS on LCT/MCT propofol and LCT propofol gave score as 0 and 23.5 (P=0.0019). CONCLUSIONS: Propofol with emulsion of long- and medium-chain triglycerides appears to reduce the injection pain than with emulsion of only long-chain triglycerides.