The relationship of brain catecholamine levels to enflurane requirements among three strains of mice with different anesthetic sensitivities.

Purpose: . It has been reported that brain catecholamines alter the minimum alveolar concentration (MAC) of anesthetics. The extent of the relation between the levels of brain catecholamine and anesthetic sensitivity should be evaluated by excluding several factors.

[Supplement of ulinastatin on renal function after cardiopulmonary bypass].

The effects of Miraclid (ulinastatin) on renal tubular function after open thorax surgery under cardiopulmonary bypass were investigated. On the 3rd day after open thorax surgery, which had lasted more than 127 min under cardiopulmonary bypass, the levels of urinary ulinastatin in the Miraclid group and control (without Miraclid) were 170 IU.mg Cr-1 and 95 IU.

Repetitive post-training exposure to enflurane modifies spatial memory in mice.

Background: Previously the authors found that a single post-training exposure to enflurane or isoflurane, but not halothane, enhanced memory storage in an active avoidance task, which is a behavior with underlying mechanisms that are poorly understood and still debated. In contrast, spatial tasks are known to depend on hippocampal functions. This study investigated the effects of repetitive post-training exposure to enflurane on spatial memory in mice.

Psychomotor performance during initial stage of exposure to halothane, enflurane, isoflurane and sevoflurane in mice.

1. The dose-response relationship during the pre-anaesthetic and pre-equilibrium state of four inhalation anaesthetics (halothane, enflurane, isoflurane and sevoflurane) on fixed-ratio schedule-controlled behaviour was studied in mice. 2.

[Urinary excretion of ulinastatin and NAG after cardiopulmonary bypass].

Although urinary trypsin inhibitor (ulinastatin, UTI) is excreted into urine, its physiological function has not been clarified well. Administration of UTI during surgical procedure was reported to protect renal function from surgical stress. This result suggests participation of UTI excretion in renal tubular function.

[Effects of ulinastatin on postoperative renal function in hepatectomized patients with liver cirrhosis].

Posthepatectomy patients with liver cirrhosis have a high incidence of multiple organ failure including renal failure. The depression of urinary ulinastatin (UTI) might be involved in renal derangements in the posthepatectomy patients with liver cirrhosis. We evaluated the relationship between the renal functions and the level of urinary UTI in perioperative period in the posthepatectomy patients with liver cirrhosis, and evaluated whether or not the renal function in the posthepatectomy patients with liver cirrhosis was protected by receiving synthetic UTI, Miraclid.

[Significance of postoperative elevation of urinary ulinastatin after open heart surgery under cardiopulmonary bypass].

To investigate the role of ulinastatin in perioperative stress, we measured the urinary levels of ulinastatin (UTI) in patients subjected to open heart surgery under cardiopulmonary bypass. The UTI levels began to increase on the first postoperative day and reached its maximum level on the third postoperative day. There is a good correlation between the maximum level of urinary UTI and cardiopulmonary bypass time.

Multiple but different genetic factors underlie enflurane and isoflurane requirements studied through backcross analysis in C57BL and ddN mice.

We performed a classic backcross analysis to examine the basic genetic nature of enflurane (ENF) and isoflurane (ISO) anesthetic requirement in two inbred mice strains, C57BL (BL) and ddN. We have previously reported different ENF and ISO anesthetic requirements in these two strains. BL (n = 22) and ddN (n = 26) mice were used as parents and were reciprocally crossed to produce F1 hybrid mice.

[Changes of urinary ulinastatin and serum CRP after elective surgery for gastric cancer].

Urinary ulinastatin (UTI) is elevated in various conditions, such as renal disease, myocardial infarction, neoplasm, leukemia and normal pregnancy. The purpose of the present study is to measure the change of UTI after surgery for gastric cancer and to compare with other acute phase reactants. Urine samples were collected from 7 surgical patients.

[Postoperative urinary ulinastatin secretion and renal function in hepatectomized patients with and without liver cirrhosis].

We compared ulinastatin secretion into urine with renal function during postoperative period in three groups, hepatectomized group with liver cirrhosis (LC(+), n = 7), hepatectomized group without liver cirrhosis (LC(-), n = 4) and subtotal gastrectomized group with normal liver function (GR, n = 7). In LC(+) group, N-acetyl-beta-D-glucosaminidase (NAG) increased above normal upper limit throughout the postoperative period. Ulinastatin (UTI) also increased but the increase was not remarkable.

[Effects of ulinastatin on postoperative renal function after cardiopulmonary bypass].

The effects of ulinastatin on postoperative renal function after the open cardiac surgery under cardiopulmonary bypass (CPB) were studied. N-acetyl-beta-D-glucosaminidase in urine as a marker of tubular function and serum creatinine rose significantly after CPB in the control group but not in the ulinastatin group. Ulinastatin was considered to be effective in protection of tubular function after CPB.

[A case of beneficial effect of ulinastatin on postoperative renal function in a patient with acute renal failure].

We experienced a case in which ulinastatin may have been beneficial to improve postoperative renal function in a patient with acute renal failure. The patient had acute renal failure with serum Cr of 9.3 mg.

[Effects of ulinastatin on renal function after subrenal aortic cross-clamping].

Ten patients who had undergone temporary occlusion of the abdominal aorta below the origin of the renal arteries were studied to evaluate the effect of ulinastatin on the postoperative renal function after abdominal aortic cross-clamping. They were divided into two groups: ulinastatin group (ulinastatin 300,000 units.day-1 during intraoperative and postoperative three days, N = 5), control group (N = 5).

Volatile anaesthetics as central nervous system excitants.

Volatile anaesthetics (VAs) act essentially as central nervous system (CNS) depressants. However, many evidences obviously demonstrate that VAs are also CNS excitants. In this review, we adduce our previous studies which are relevant to the behavioural evidences of the CNS excitation actions of VAs.

Anaesthetic mechanism--from molecular to biological aspects.

The mechanism of anaesthesia is still a black box, although many investigators have been concerned about this theme since the 19th century. It is too complex to clarify the mode of anaesthetic action, as a variety of compounds have been adopted as anaesthetics. Hill coefficients calculated from the righting reflex dose-response curve in enflurane, isoflurane sevoflurane and halothane anaesthesia in a certain strain of mice were from 14 to 56.

Differential effects of isoflurane, halothane, and ketamine on the regional methionine-enkephalinlike immunoreactivity in the mouse brain.

The widely used measurement index for anesthetic potency, minimum alveolar concentration (MAC), is hypothesized to be the sum of the effects on multiple neural systems whose contribution to anesthesia differs depending on the agents used. The present study, which compared the effects of halothane, isoflurane, and ketamine, at equipotent level of anesthesia, on the methionine-enkephalinergic neurons in 9 brain regions, showed a significant difference in the methionine-enkephalin-like immunoreactivity (Met-ENK-like IR) among the anesthetics in each region. The order of the Met-ENK-like IR was: halothane > ketamine > isoflurane in the caudatus putamen; halothane > isoflurane ≊ketamine in the nucleus accumbens and the ventral pallidum; halothane ≊isoflurane > ketamine in the globus pallidus, the nucleus dorsomedialis hypothalami, and the nucleus ventromedialis hypothalami; and halothane > isoflurane > ketamine in the arcuate nucleus, the periaqueductal gray, and the nucleus reticularis parvocellularis.

Possible participation of NMDA and glycine receptors but not GABAA receptors in enflurane-induced opisthotonus in mice.

1. We previously reported that volatile anaesthetics produce incidences of a transient opisthotonus in mice, a sign of CNS stimulation. This study was performed to investigate mechanisms by which enflurane-induced opisthotonus (EIO) occurs.

The N-methyl-D-aspartate (NMDA) receptor antagonist dizocilpine (MK-801) suppresses enflurane-induced opisthotonus in mice.

We determined whether enflurane-induced opisthotonus in ddN mice is mediated by N-methyl-D-aspartate (NMDA) receptor using NMDA receptor antagonists dizocilpine (MK-801) and ketamine. Animals were given intraperitoneal injections of 0.2 ml saline (control), 2.

Memory facilitation by posttraining exposure to halothane, enflurane, and isoflurane in ddN mice.

The effect of low and high concentrations of halothane, enflurane, and isoflurane on posttraining memory function was studied in male ddN mice. Mice were trained to escape an aversive electric foot shock as an unconditioned stimulus within 3 s after being exposed to light and a buzzer as a conditioned stimulus. Immediately after training (first session: 30 trials), the animals were exposed to halothane, enflurane, or isoflurane for 120 min and then were tested again on the avoidance task (second session: 30 trials) 22 h after cessation of exposure.

Strain-differences of sensitivity to volatile anesthetics and their genetic character in mice.

Using loss of the righting reflex, we determined the ED50 values for enflurane, isoflurane, sevoflurane and halothane in white-haired ddN mice and black-haired C57BL mice. The ED50s (Mean +/- SEM) in ddN and C57BL mice for enflurane were 1.65 +/- 0.

Subanesthetic concentrations of volatile anesthetics may enhance acquired avoidance training in ddN mice.

The effects of halothane, enflurane, and isoflurane on avoidance training were assessed in male ddN mice. Animals were trained to escape an aversive unconditioned stimulus (electric foot shock) within 3 s after being exposed to a conditioned stimulus (light and buzzer). Immediately after training (first session), the animals were exposed to halothane, enflurane, or isoflurane for 120 min and were then tested again on the avoidance task (second session) 30 min after cessation of the exposure.

The effects of age and anesthetic solubility on anesthetic-induced opisthotonus in mice.

In our previous report which indicated volatile anesthetics-induced opisthotonus in mice, we hypothesized that opisthotonus might relate with the rapidity of anesthetic induction, i.e., the blood/gas partition coefficient of the agent.