Abstract:
Pharmaceutical compositions containing 2-amino-6-benzyl-3-ethoxycarbonyl-4,5,6,7-tetrahydro-thieno[2,3-c]pyridine hydrochloride and a method of using such compositions in treatment of liver dysfunction in mammals are disclosed.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to pharmaceutical compositions containing 2-amino-6-benzyl-3-ethoxycarbonyl-4,5,6,7-tetrahydro-thieno-[ 2,3-c] pyridine hydrochloride, and to a method of using such compositions in treatment of liver dysfunction in mammals. 
     2. Description of the prior art 
     2-Amino-6-benzyl-3-ethoxycarbonyl-4,5,6,7-tetrahydro-thieno-[ 2,3-c]pyridine hydrochloride (hereinafter called tinoridine hydrochloride by generic name) of the formula ##STR1## is disclosed in U.S. Pat. No. 3,563,997, and has utility as analgesic and antiinflammatory agent. 
     SUMMARY OF THE INVENTION 
     The present invention provides a new use for tincridine hydrochloride, namely the application of this agent to the treatment of liver dysfunction in mammals, e.g. in humans. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention has been accomplished on the basis of new finding that tinoridine hydrochloride shows highly protective effects on liver injuries of animals caused by carbon tetrachloride, thioacetamide and D-galactosamine. Such excellent pharmacological efforts are recognized as being indicative of effect in humans who are afflicted with liver dysfunction such as acute and chronic hepatitis, liver cirrhosis, fatty liver and toxic hepatitis induced by ethanol, organophosphorus insecticide, chloroform, carbon tetrachloride and so on. (see, for example, Arzneimittel-Forschung, vol. 18, 698 (1968) and vol. 21, 1194, 1209 (1971)) 
     Protective effects of tinoridine hydrochloride on experimental disturbances in the rat liver are shown below: 
     I. Methods 
     1. Protective effect against acute liver injury by carbon tetrachloride 
     Essentially the test was performed according to the method described by Von G. Hahn et al. in &#34;Arzneimittel-Forschung&#34;, vol. 18, 698 (1968). 
     Carbon tetrachloride (CCl 4 ) was dissolved in olive oil and injected intraperitoneally at a dose of 0.25 ml/kg to male Wistar rats (about 200 g). Then serum glutamic oxalacetic transaminase (S-GOT) and serum glutamic pyruvic transaminase (S-GPT) were determined by AutoAnalyser AA-II (Technicon Corporation) 24 hours after the CCl 4  injection. The test compound (tinoridine hydrochloride) was administered orally one hour before the CCl 4  injection. The results are shown in Table I. 
     2.  Protective effect against acute liver injury by thioacetamide 
     The test was also performed essentially according to the method mentioned above. 
     Thioacetamide was dissolved in water and injected subcutaneously at a dose of 50 mg/kg to male Wistar rats (about 200 g). Then S-GOT and S-GPT activities were determined by AutoAnalyzer AA-II 24 hours after the thioacetamide injection. The test compound was administered orally one hour before the thioacetamide injection. The results are shown in Table II. 
     3. Protective effect against acute liver injury by D-galactosamine 
     Essentially the test was performed according to the method described by D. Keppler et al. in &#34;Experimental and Molecular Pathology&#34;, vol. 9, 279 (1968). To Wistar rats (about 200 g) fasted for 24 hours, 100 mg of D-galactosamine in 1 ml of saline solution was injected intraperitoneally and 4 hours later an additional 50 mg of D-galactosamine in saline solution was injected. Then S-GOT and S-GPT activities were determined by AutoAnalyzer AA-II 7 hours after the initial injection of D-galactosamine. The test compound was administered twice orally each one hour before the D-galactosamine injection. The results are shown in Table III. 
     
                                           TABLE I__________________________________________________________________________      No. of          S-GOT       S-GPTTreatment  Rats          (mU/ml)     (mU/ml)__________________________________________________________________________Normal Control      5   176±9**                 (100)                       55±2**                             (100)CCl.sub.4 Control      5   2,848±646                      1,790±355CCl.sub.4 + TinoridineHydrochloride10 mg/kg   5   2,184±701                 (25) 1,299±415                             (28)40 mg/kg   4   1,274±147                 (59)  666±110* (65)160 mg/kg  5    971±104*                 (70) 531±94*                             (73)__________________________________________________________________________ Mean ± S.E. *p&lt;0.05, **p&lt;0.01 vs. CCl.sub.4 Control The values parenthesized in Table I represent % inhibition. 
    
     
                                           TABLE II__________________________________________________________________________          No. of              S-GOT        S-GPTTreatment      Rats              (mU/ml)      (mU/ml)__________________________________________________________________________Normal Control 4    180±11**                      (100)                            66±4**                                   (100)Thioacetamide Control          6   1,818±268 996±154Thioacetamide + TinoridineHydrochloride25 mg/kg       7   1,194±126*                      (38) 629±81*                                   (39)50 mg/kg       6    889±181**                      (57)  488±102**                                   (55)100 mg/kg      7    732±125**                      (66)  389±73**                                   (65)200 mg/kg      7    798±89**                      (62)  425±54**                                   (62)400 mg/kg      3    433±121**                      (85)  203±67**                                   (85)__________________________________________________________________________ Mean ± S.E. *p&lt;0.05, **p&lt;0.01 vs. Thioacetamide Control The values parenthesized in Table II represent % decrease vs. Thioacetamide Control. 
    
     
                                           TABLE III__________________________________________________________________________           No. of                S-GOT        S-GPTTreatment       Rats (mU/ml)      (mU/ml)__________________________________________________________________________Normal Control  5    139±3**                        (100)                              42±2**                                     (100)D-Galactosamine Control           5    1,907±177 1,141±134D-Galactosamine + TinoridineHydrochloride25 mg/kg × 2           5     1,218±159*                        (39) 627±99*                                     (47)__________________________________________________________________________ Mean ± S.E. *p&lt;0.05 **p&lt; 0.01 vs. D-Galactosamine Control The values parenthesized in Table III represent % decrease vs. D-Galactosamine Control. 
    
     In the histopathological studies, tinoridine hydrochloride has been found to improve necrosis, e.g. centrolobular necrosis caused by CCl 4 , and focal necrosis caused by D-galactosamine. 
     The results of comparative studies of protective effect against liver injuries in rats by CCl 4  and thioacetamide are shown in Table IV. The testing methods are the same as mentioned above. 
     
                       TABLE IV______________________________________Test           Dose      Protection %.sup.a) of S-GPTCompound       mg/kg, p.o.                    CCl.sub.4                            Thioacetamide______________________________________Tinoridine Hydrochloride           50       65      43          100       84      71Indomethacin   2.5       21      -11Phenylbutazone 100        9      24Ibuprofen      100       -27      7Prednisolone    10       -26     84Clutathione    250 (i.p.)                    31      -62______________________________________.sup.a) The percent inhibition is calculated by the following formula; ##STR2## 
    
     As is seen from the data in Table IV, other known antiinflammatory agents (indomethacin, phenyloutazone, ibuprofen and prednisolone) and glutathione cannot be said to have very excellent protective affects on experimental liver injuries. Only tinoridine hydrochloride has quite potent effects. 
     In view of various tests, including those mentioned above, tinoridine hydrochloride can be safely administered for the treatment of liver dysfunction in mammals, e.g. in humans such as mentioned previously, in the form of a pharmaceutical preparation with a suitable and conventional carrier, without adversely affecting the patients. 
     The pharmaceutical preparation can take any conventional form of capsules, tablets and powders for oral administration, or of suppositories for topical administration. For example, 50 mg and 100 mg capsules are prepared from the following compositions: 
     
         ______________________________________         50 mg Capsules                   100 mg Capsules______________________________________Tinoridine Hydrochloride           55.8 mg*    111.6 mg**Lactose         50.0        50.0Starch          42.0        35.0Methylcellulose 1.2         2.0Magnesium Stearate           1.0         1.4Total           150.0 mg    200.0 mg______________________________________  * equivalent to 50 mg of the base ** equivalent to 100 mg of the base 
    
     The daily dose of tinoridine hydrochloride for human adults suffering form liver dysfunction usually ranges from about 300 mg to 600 mg, i.e. 6 to 12 capsules, each capsule containing 55.8 mg. (equivalent to 50 mg of the base) of tinoridine hydrochloride, in single or multiple dose, but it may vary depending upon the age, body weight, and/or severity of the condition to be treated as well as the response to the medication. 
     Although the present invention has been adequately discussed in the foregoing specification, one readiy recognizes that various changes and modifications may be made without departing from the spirit and scope thereof.