JPH0458451B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to an agent for improving brain metabolic disorders, and particularly to an agent for improving brain metabolic disorders, which contains human urinary kallidinogenase as an active ingredient. (Prior art) Kallidinogenase is an enzyme produced in the pancreas and excreted in the urine. It forms kallidin from kininogen, has a direct or indirect effect on water electrolyte metabolism in the kidney, and acts on the antihypertensive system. It is thought to be useful as a therapeutic agent for various circulatory system disorders such as hypertension, peripheral vascular disorders, and angina pectoris. Conventionally, kallidinogenase extracted mainly from pig pancreas has been administered orally or by injection for the purpose of treating the above-mentioned circulatory system disorders. Since the amount of kallidinogenase that reaches the target is extremely small, administration of large amounts and over a long period of time is required, and as a result, side effects may occur. From this safety standpoint, kallidinogenase, which is derived from human urine instead of pig pancreas, has recently attracted attention. (Problems to be Solved by the Invention) Kallidinogenase is an enzyme protein, and has a problem in that it has relatively low stability and is easily deactivated in a short period of time. Therefore, the aim during the research process related to the present invention was to improve the stability of kallidinogenase. (Means and Effects for Solving the Problems) The present inventors have conducted intensive studies on the stabilization method, pharmacological action, therapeutic effect, etc. of kallidinogenase of various origins, and found that basically human urinary kallidinogenase was extracted with citric acid. The present invention was basically completed by discovering that deactivation can be suppressed for a long period of time when sodium is coexisted with sodium. As a result of further investigation into the pharmacological effects of this stabilized human urinary kallidinogenase, we found that it was not only used for the treatment of hypertension and peripheral vascular disorders, which were previously known, but also for the treatment of cerebral metabolic disorders. It was also found that this method is also effective, leading to the completion of the present invention. That is, the present invention is based on the discovery of a new pharmacological action of human urinary kallidinogenase through stabilization. Therefore, according to the present invention, there is provided an agent for improving cerebral metabolic disorders containing human urinary kallidinogenase as an active ingredient, characterized in that it contains human urinary kallidinogenase and 0.1-10% by weight of sodium citrate. be done. The agent for improving brain metabolic disorders according to the present invention can be administered either intravenously or orally, and in the former case, sodium citrate 0.1-1
In the latter case, the content is preferably 3-10% by weight. Human urinary kallidinogenase, which is the main component of the agent for improving brain metabolic disorders according to the present invention, can also be modified with a stabilizing derivative such as polyethylene glycol. When the brain function improving agent according to the present invention is in an intravenous administration form, the carrier for the preparation can be physiological saline, and in the case of a powder for injection, it can be dissolved in physiological saline at the time of use. On the other hand, in the case of oral administration forms such as tablets, excipients, disintegrants, etc. may be contained. The amount of kallidinogenase to be added is determined depending on the type and severity of the disease, but in the case of injections, it is preferably set within the range of 1-100 international kallidinogenase units (IU)/g, and for oral administration. In the case of tablets for use, it is preferably within the range of 1-100 IU/g [Kallidinogenase activity is indicated by “KU”,
"KE" etc. were used, but later it was unified to "IU" or "International Unit." A specific explanation will be given.Reference example (Production method of modified kallidinogenase) 2-o-methoxypolyethylene glycol-
200 mg of 4,6-dichloro-S-triazine and 25 mg of kallidinogenase were reacted in a 0.1 M borate buffer under low temperature conditions for 2 hours, and then ultrafiltered.
Polyethylene glycol-modified kallidinogenase was obtained by freeze-drying. Production example 1 (injection) Sodium citrate was added to human urine kallidinogenase solution whose concentration was adjusted to 50 KI/ml to make the sodium citrate concentration 3%, heated to 70°C and held for 20 hours to sterilize it. An injection powder was obtained by desalting by dialysis and freeze-drying (in this case, almost no loss in the potency of kallidinogenase was observed). By adding physiological saline, dissolve the above lyophilized powder and increase the concentration of kallidinogenase.
After adjusting to 50 KI/ml, the solution was dispensed into 3 ml ampoules. Production example 2 (Oral administration tablet) Sodium citrate was added to human urinary kallidinogenase stock solution to adjust the citric acid concentration to 3% and at 70°C.
The mixture was sterilized by heating to 10 hours and then freeze-dried. Excipients and the like were added to this freeze-dried powder in a conventional manner and the mixture was compressed to obtain tablets each containing 50 IU of kallidinogenase. Test Example 1 (Stability Test) Lyophilized powders for injection were prepared in the same manner as in Production Example 1, except that the concentration of sodium citrate was set to 0.5% and 1.0%. Each powder for injection was dissolved in physiological saline, the kallidinogenase concentration was adjusted to 15 KI/ml, and the test sample was prepared. On the other hand, a solution of kallidinogenase at the same concentration that does not contain sodium citrate and a solution of modified kallidinogenase at the same concentration that does not contain sodium citrate (the one using the modified and stabilized kallidinogenase described in the reference example) were used as controls. And so. The above two types of test subjects and two types of controls were placed in vials and stored at room temperature for 90 days, and the residual titer rate of kallidinogenase was measured over time. The results are as shown in the drawing. Ta. The test results revealed that the coexistence of sodium citrate contributed to the stabilization of kallidinogenase, and that the appropriate amount of sodium citrate for stabilization purposes was 1.0% or more. Although there is no particular upper limit to the amount of sodium citrate added, the effect of addition reaches a plateau at about 10% by weight. Test Example 2 (Acute Toxicity Test) Kallidinogenase is an enzyme (glycoprotein) produced by living organisms, and its toxicity varies depending on the species of animal of origin, and physicochemical differences are also observed depending on the animal of origin. Therefore, it is difficult to be certain of the safety of clinical use from the results of animal experiments, but the acute toxicity when human urine kallidinogenase is administered orally or intravenously to rats is as follows. It can be said that the toxicity of the cerebral metabolic disorder improving agent is quite low.

[Table] Test Example 3 (Brain metabolism promotion effect) (a) Test method Male Wistar rats weighing 320-400 g 5
The animals were used as experimental animals and were anesthetized with pentobarbital. The lyophilized powder for injection according to Production Example 1 was dissolved in physiological saline, and 0.21 ml (3 IU of kallidinogenase) was injected into the cerebellobulbar cistern, and the administration effect was examined by visual observation of behavior. (b) Test results Hyperexcitability and clonic spasticity were observed 3 to 5 minutes after administration, and spontaneous activity, which continued for 4 to 5 minutes, was reduced, leading to a state of depression. . When stimulated with a stick, the animal exhibited spinning and jumping behavior, but then showed a depressed state again. Test Example 4 (Brain metabolism promoting effect) Three tablets according to Manufacturing Example 2 were administered to three people who were recognized to have a hangover. () Improved, () I think it is improving, () Unknown, and () Worsened. When we conducted a questionnaire survey regarding the treatment effects in four categories, all of the respondents answered that they had ``improved'' or ``I think they are improving.'' (Effect of the invention) As a pharmacological action of kallidinogenase, the effect of improving cerebral metabolic disorders was not known until now, but as a result of improving the stability of human urinary kallidinogenase by coexisting with sodium citrate, it is possible to administer it intravenously or orally. The pharmacological effect is expressed.

[Brief explanation of the drawing]

The accompanying drawing is a graph showing the results of examining changes over time in the residual potency of kallidinogenase when the injection solution of the agent for improving cerebral metabolic disorder according to the present invention and the conventional kallidinogenase injection solution were stored at room temperature.

Claims (1)

[Scope of Claims] 1. An agent for improving cerebral metabolic disorders containing human urinary kallidinogenase as an active ingredient, characterized in that it contains human urinary kallidinogenase and 0.1-10% by weight of sodium citrate. 2. The agent for improving cerebral metabolic disorders according to claim 1, which contains 0.1-1% by weight of sodium citrate and is administered in an intravenous form. 3. The agent for improving cerebral metabolic disorder according to claim 1, which contains 3-10% by weight of sodium citrate and is in an oral administration form. 4. The agent for improving cerebral metabolic disorder according to any one of claims 1 to 3, wherein the cerebral metabolic disorder is alcohol poisoning due to drinking.