Local anesthetic and antiarrhythmic effect of some imidazolidin-2-one derivatives

LOCAL ANESTHETIC AND ANTIARRHYTHMIC EFFECT OF SOME IMIDAZOLIDIN-2-ONE DERIVATIVES

T A D E U SZ LIBRO W SKI, B A R B A R A FILIPEK and R Y SZ A R D CZA RN ECK I

Department o f Pharmacodynamics, C ollegium M edicum Jagiellonian U niversity, 9 M edyczna Str., 3 0 -6 8 8 Krakow, Poland

A b s t r a c t : A s e rie s o f th e n e w d e riv a tiv e s o f im id a z o lid in - 2 - o n e w a s in v e stig a te d in o rd e r to d e te rm in e th e ir lo c al a n e sth e tic a n d an tia rrh y th m ic a c tiv ity . A ll c o m p o u n d s te ste d sh o w e d stro n g lo cal a n e sth e tic p ro p e rtie s a n d v a ria b le e ffe c ts o n a d r e n a lin e - , a c o n itin e - a n d b a riu m c h l o r id e - in d u c e d a rrh y th m ia . T h e re su lts su g g e s t th a t th e an tia rrh y th m ic p ro p e rtie s o f th e se c o m p o u n d s is re la te d to th e ir lo c al a n e sth e tic p ro p ertie s.

K e y w o r d s : lm id a z o lid in - 2 - o n e d e riv a tiv e s - lo c a l an e sth e tic s - a n tia rrh y th m ic a c tiv ity .

The local anesthetic effect is characteristic for the antiarrhythmic drugs o f I class, i.e. drugs w hich stabilize the cellular membranes and m odulate sodium channel activity (2, 3, 14, 15). N um erous earlier studies suggested correlation betw een so- dium -channel antagonists o f this class and its antiarrhythmic activity (3, 4 , 11).

The subject o f this study w as anesthetic effect and antiarrhythmic effect o f new im id azolid in - 2-o n e derivatives, w hich were synthesized in the Department o f C hem ical T echnology o f drugs in the Faculty o f Pharmacy o f the M edical Academ y in Gdańsk (Table 1).

MATERIALS AND METHODS

Com pounds used

Epinephrine (Adrenalinum hydrochloricum Polfa), aconitine (A conitinum nitricum in subst., Toscat), barium chloride (POCh G liw ice), lidocai- ne (Lignocainum hydrochloricum , Polfa), pentotal (Thiopental sodium B.P., Abbott Laboratories), propranolol (Propranololum hydrochloricum , Pol­

fa), quinidine sulfate (Polfa).

Anim als

T he studies were carried out on m ale A lbino S w iss (w eight 1 8 -2 4 g), m ale W istar rats (w eigt 1 4 0 -2 2 0 g) and guinea pigs o f both sexes (w eight 3 0 0 -3 5 0 g). A nim als were housed in wire mesh cages in a room at 2 0 + 2°C with natural light-dark cycles. The anim als had free access to standard pellet diet and water, and used after a minim um o f 3 days acclim ation to the housing conditions. C ont­

rol and experim ental group consisted o f 8 -1 0 anim als each.

D o ses and routes o f administration

D epending on the experim ental method, the tested com pounds were given intravenously, in doses corresponding to 1/2 0 , 1/ 10, 1/5 and 2/5 L D 50 or intradermally and topically, in the form o f 0,5, 1 and 2 % stolutions.

Statistical analysis

The data are expressed as m eans ± SEM.

Student’s t-test w as used to determ ine the sig ­ nificance betw een mean values o f control and treatment groups. D ifferences were considered sig ­ nificant w hen p<0.05.

EC50 values and their confidence lim its were calculated according to the m ethod o f Litchfield and W ilcoxon after 30 min observation.

I. L ocal anesthetic activity acc. to Biilbring and Wajda (1)

A. Corneal anesthesia

T he com p ou n d s studied w ere in stilled to the right con ju n ctival sac as a 0,5; 1,0 and 2,0%

so lu tio n s in the sam e v o lu m e 0 ,0 5 m l, on the contrary to the le ft e y e the sam e v o lu m e o f 0,9%

N aC l.

T he corneal reflex w as exam ined by irritation a right ey e conjunctiva (studied ey e) and a left eye conjunctiva (control ey e) by horse’s hair. The strength o f local anesthetic activity w as determined from the m om ent o f solution instillation to the m om ent o f reflex return. The presence or lack o f corneal reflex were considered during an activity assessm ent. The eye conjunctiva irritation w as done 6 tim es (every 5 sec) in the pause o f 5 minutes during the first 3 0 minutes. T he sum o f the ir­

391

392 T A D E U SZ LIBROW SKI et al.

ritation, for what guinea pig did not react to each o f the above concentrations (in %) served to assess

E C 5 0 .

B. The infiltration anesthesia (intradermal wheal test)

The infiltration anesthesia w as done on guinea pig, causing the intradermal w heal by injection to the dorsum skin com pounds studied in volum e 0,1 ml and dosages 0,5; 1,0 or 2,0%.

The painful reaction to prick w as registered pricking 3 tim es the skin at the center o f the wheal (every 5 sec) in 5 minutes intervals during the first 30 minutes o f observation and next after 15 minu­

tes. Experiment w as continued to achieve the return o f reaction for a prick.

The control w heal w as done by an intradermal injection o f 0,1 ml 0,9% N aCl. The comparable studied o f duration tim e o f infiltration anesthesia in guinea pigs w ere done using lidocaine in dosage 0,1; 0,5 and 1,0%. The differences betw een control and studied groups were estim ated by EC50.

II. Prophylactic antiarrhythmic activity

A . A drenaline-induced arrhythmia acc. to Szekeres (13)

The arrhythmia w as evoked in rats anestheti­

zed with thiopental (75 m g/kg, ip) by intravenous injection o f adrenaline (2 0 p g/k g, in volum e o f 1 m l/kg animal w eight). The studied com pounds were administered intravenously 15 min before adrenaline. Evaluation o f the antiarrhytmic activity w as made acc. to the tim e o f occurring postad­

renaline disorders and the survival tim e o f animals in control and studied group. ECG w as recorded on a Multicar E -3 or E - 3 0 apparatus, using the stan­

dard lim b lead, and the tape speed 50 mm /s.

B. A con itin e-in d u ced arrhythmia acc. to Szekeres (13)

The arrhythmia w as evoked in rats anestheti­

zed with thiopental (75 m g/kg ip) by iv injection o f aconitine (10 pg/kg). The investigated com pound w as given iv 15 m inutes before the arrhythmogen (prophylactic activity). The tim e o f onset o f severe ventricular arrhythmia’s or the tim e restoration o f the sinus rhythm and mortality in a particular group were accepted as a criterion o f evaluation.

C. Barium chloride-induced arrhythmia acc. to Szekeres (13)

Barium chloride solution w as injected into the caudal vein o f rat (32 m g/kg, in a volum e o f 1 m l/kg). The investigated com pound w as given iv

15 minutes before the arrhythmogen. The criterion o f antiarrhytmic activity w as a gradual disappea­

rance o f the arrhythmia and restoration o f the sinus rhythm.

III. A cu te to x ic ity acc. to L itch field and W il- c o x o n (6 )

A cute toxicity w as assessed according by the method o f Litchfield and W ilcoxon and presented as L D 50 calculated from the mortality o f m ice after 24 hours.

RESULTS

I. Local anesthetic effect

A . Corneal anesthesia

The new derivatives o f im id a zo lid in -2 -o n e applied into the conjunctival sac in a concentration o f 0,5; 1,0 and 2,0% did not exert local anesthetic activity.

B. Infiltration anesthesia

C o m p o u n d B F -1 7, B F -1 8 , B F - 1 9 a n d B F - 2 0 , injected intradermally at concentrations o f 0 ,5-2% , show ed strong anaesthetic effect. The strongest effect, higher than that lidocaine, w as show n by com pound B F - 1 9 and B F -2 0 . Com pounds B F - 1 7 and B F -1 8 produced an effect sim ilar to that o f lidocaine. The duration tim e o f anesthesia after tested com pound w as 2 - 4 h and w as considerably longer than that o f lidocaine (4 0 - 5 0 min). A d­

ministration o f com pound B F -2 1 and B F -2 2 was im possible to cause a low solubility o f this com ­ pounds. The EC50 values determ ined after 30 min observation period are presented in Table 2. The data reported in Table 2 indicate that the therapeu­

tic index o f investigated com pounds w as more favorable than for lidocaine.

Prophylactic antiarrhythmic activity

A . A drenaline-induced arrhythmia

The intravenous injection o f adrenaline, in the dose o f 20 ftg/kg, caused ventricular tachycardia and supraventricular ectopic beats. A ll new com ­ pounds administered iv 15 min before adrenaline in doses o f 1/10 to 2/5 L D 50, contrary to propranolol (E Djo- 1 ,0 5 (0 ,6 4 -0 ,7 3 ) did not prevent adrenali­

ne-induced disturbances. Only com pound B F - 1 7 and B F -1 8 given in highest dose show ed low est antiadrenaline activity (Figure 1).

B. A conitine-induced arrhythmia

A conitine (10 pg/kg iv) caused in rats at-

T a b le 1. A c u te to x ic ity (L itc h fie ld , W ilc o x o n ). T im e : 2 4 h , R o u te : iv. A n im a l: m o u se

rioventricular conduction disorders, ventricular ta­

chycardia and ventricular fibrillation, ending very often by deaths o f anim als after 1 2 -1 5 minutes.

The study results o f influence o f investigated compounds on arrhythmogenic effects caused by intravenously administered aconitine were showed in Table 3. The antiarrhythmic activity o f BF com ­ pounds was evaluated on the basis o f time delay o f arrhythmia appearance and extension o f animal time survival. All the compounds studied, to be sure, exerted the prevention influence on animals mortality, caused by aconitine intravenously administered, made however in the high dosage equal to 2/5 LD 5n.

The BF series com pounds in the dosage 2/5 LD 50 intravenously administered 15 minutes before aconitine injection caused appearance delay o f the arrhythmia with very mean decrease o f the vent­

ricular heterotropy. The relative high activity strength distinguished the B F -1 9 compound. The intravenous dosages o f this compound in 2/5 L D 50, administered 15 minutes before the aconitine injec­

tion, led to delay o f the disorders o f the rhythm from 60 sec in control to 390 sec the groups studied.

Therefore the B F -1 9 com pound delayed at 550% appearance period o f the aconitine arrhyth­

mia and protected also before appearance o f toxic

394

F ig u re I. A n tia rrh y th m ic a c tiv ity o f th e in v e stig a te d c o m p o u n d s o n th e a d re n a lin e -in d u c e d a rrh y th m ia . A n im a l: ra t. w e ig h t 140 - 2 2 0 g , N = 8 - 10

A rrh y th m o g e n : a d re n a lin e , 2 0 g g /k g i.v.

C o m p o u n d s: iv 15 m in b e fo re th e a rrh y th m o g e n

T a b le 2. L o c al a n e sth e tic a c tiv ity o f in v e stig a te d c o m p o u n d s

Compound Concentration Activity EC,,,

....

TI

(%) (%) (%) (LDji/EC,,,)

0.1 39.0 0.36

Lidocaine 0.5 59.3 (0.18-0.74) 83.33

1.0 87.0

0.5 50.0 0.52

BF-17 1.0 67.6 (0.28-0.92) 142.31

2.0 89.4

0.5 71.3 0.31

BF-18 1.0 80.8 (0.15-0.69) 187.09

2.0 96.7

0.5 76.9 0.105

BF-19 1.0 73.2 (0.098-0.210) 476.19

2.0 89.1

0.5 82.5 0.101

BF-20 1.0 85.5 (0.086-0.198) 564.45

2.0 87.9

Results are expressed as a mean ±SEM ; N =8-I0.

The EC50 values are given with 5% confidence limits.

p h a s e - e x te n d e d th e a n im a l s u rv iv a l tim e s . T h e a n im a l m o ra lity y ie ld e d p ro lo n g a tio n ( B F - 1 9 ) a b o u t 2 6 % to c o m p a re w ith th e c o n tro l g ro u p g e ttin g o n ly a lo n e a c o n itin e .

B F - 1 7 c o m p o u n d s im ila r a n tia rr h y th m ic an d a n tito x ic a c tiv ité s s h o w e d . B F - 1 7 a d m in is te re d in tra v e n o u s ly in th e d o s a g e o f 2/5 L D W b e fo re a c o n itin e in je c tio n d e la y e d at a b o u t fiv e tim e s

T a b le 3. A n tia rrh y th m ic a c tiv ity o f th e in v e stig a te d c o m p o u n d s in a c o n itin e -in d u c e d arrh y th m ia . A n im a l: W is ta r rates, w e ig h t 1 4 0 -2 2 0 g

A rry th m o g e n : ac o n itin e , 10 Jig /k g i.v.

C o m p o u n d s : i.v. 15 m in b e fo re th e a rrh y th m o g e n

Com pound Dose

mg/kg iv 2/5 LDm

A ppearance tim e of arrhythm ia

(sec)

Prolongation tim e o f arrhythm ia

(%)

M ortality after (sec)

Survival time extension

(%)

Control 0 60 ± 11.8 - 828 ± 115 -

B F -1 7 29.6 336 ± 82.7 460 ± 2 3 .1 5 1380 ± 245 66.67 ± 5.65

B F -1 8 23.2 120 ± 34.8 100 ± 15.59 1260 ± 180 52.17 ± 0.71

B F -1 9 20.0 390 ± 87.4 550 ± 18.62 1044 ± 128 26.08 ± 1 .1 .7 9

B F -2 0 22.8 210 ± 69.7 250 ± 39.55 1008 ± 125 21.17 ± 1.02

Quinidine 30.0 130 ± 39.6 117 ± 19.21 1280 ± 195 54.59 ± 1.82

Results are expressed as a m ean ± SEM ; N=8-10

arrhytmia appearance and extended the animal survival tim es by about 67%. The observed effect w as stronger than that o f quinidine.

The other investigated com pounds (B F -1 8 , B F -2 0 ) show ed the considerable w eaker activities, but the antiarrhythmic effect o f B F -1 8 and B F -2 0 w as com parable to that reported for quinidine in the sam e procedures (Table 3).

C. Barium chloride-induced arrhythmia

A single (v dose o f 32 m g/kg BaCl2 induced progressively increasing disturbances o f cardiac rhythm, associated with premature ventricular be­

ats and ventricula fibrillation, leading to death within 2 0 -2 5 min.

The com pounds studied (B F -1 7 -2 0 ) , given in the dose o f 2 /5L D 50 did not prevent the occurrence o f heart rhythm disorders caused by barium chlori­

de. They also did not prevent before occurrence o f the toxic phase as mortality caused by barium chloride. Only B F - 1 9 and B F -2 0 extended the anim als survival tim es adequate to 2 and 6 tim es in com parison to the control group.

III. A cute toxicity

Com pounds B F - 1 7 -2 0 , applied intravenously were less toxic than lidocaine (L D 50 = 2 5 ,0 -2 7 ,5 ).

C om pound B F -2 1 and B F -2 2 , as insoluble in water, were exclude in this study. The values o f iv L D 50 in m ice are reported in Table 1.

DISCUSSION

At present four major classes are available for the m anagem ent o f cardiac arrhythmia: local anes­

thetics (class I), beta-blockers (class II), class III antiarrhythmic agents (i.e. prolongation o f repola- ryzation), and the calcium -channel antagonists (class IV ). C lass I antiarrhythmic drugs block the fast sodium channel and p ossess local anesthetic activity (2, 9, 15).

A number o f earlier studies suggested som e association betw een local anesthetic and antiarrhy­

thm ic activity (3, 4, 10, 11). It w as concluded that local anesthetic activity is not a necessary co n ­ com itant to antiarrhythmic activity and that local anesthetic activity m ight be more correctly as­

sociated with depression o f cardiac conduction and contractility (8, 11).

Previous pharm acological screening for new cardiovascular agents led to discovery o f antiar­

rhythmic and local anesthetic activity o f (-)-tr a - ns—4 -[2 -h y d r o x y -3 -(N -iso p r o p y lo a m in o )-p r o x y ] - c ic carane (5, 12). A s a continuation o f our study, w e demonstrated the local anesthetic and antiar­

rhythmic activity o f som e im id a zo lid in -2 -o n e deri­

vatives.

The obtained results indicate that the in ves­

tigated new im id a zo lid y n -2 -o n e derivatives d e­

monstrated potent local anesthetic properties when applied intradermally to the conscious guinea pig.

The effect w as stronger than that o f lidocaine. The therapeutic index o f com pound B F -1 9 ( l - { 5 - c y a - n o - 2 [ l- ( 2 - p ir o lid in e - e t h y l- c a r b a m o y l) - p r o p y l- t h i o ] - b e n z e n e - s u ! p h o n y l} - im id a z o lid y n - 2 - o n e hydrochloride) w as about six tim es, and B F -2 0 ( ( l- { 5 - c y a n o - 2 [ l[ ( 2 - p ip e r id in e - e t h y l- c a r b a m o - y l)-p r o p y l-th io ]-b e n z e n e -s u lp h o n y l} -im id a z o li- d y n -2 -o n e hydrochloride) seven tim es advantage­

ously that lidocaine.

396 T A D E U SZ LIBROW SKI et al.

T w o o f them, com pound B F -1 7 ( l - { 5 - c y a - n o -2 [ 1 -(1 -d im e th y la m in o -2 -p ro p y l-ca rb a m o y 1)- p r o p y l-th io ]-b e n z e n e -s u lp h o n y l} -im id a z o lid y n - 2 -o n e hydrochloride) and B F -1 8 ( l - { 5 - c y a n o - 2 [ l - ( 2 -d im e t h y la m in o - e t h y l- c a r b a m o y l) - p r o - p y l-th io ]-b e n z e n e -s u lp h o n y l}-im id a z o lid y n -2 -o - ne hydrochloride) given before adrenaline partially prevented the rhythm disturbances. The observed effect w as weaker than that o f propranolol, w hich w as highly effective in abolishing arrhythmia pro­

voked by the injection o f adrenaline (7).

A ll investigated com pounds delayed the o c ­ currence o f disturbances produced by the intrave­

nous injection o f aconitine in rats and prolonged the animal survival time. The observed antiarrhyth- m ic effect w as similar or stronger that the effect o f quinidine.

In comparison with control group, tested com ­ pounds, did not prevent barium -chloride induced heart dysrrhythmias, but com pounds B F -1 9 and 20 prolonged tw o -fo ld and s ix -fo ld the anim als sur­

vival time.

In summary, investigated new im idazoli- d y n -2 -o n e derivatives demonstrated potent local anesthetic properties and variable effects on ad­

renaline-, acon itin e-, and barium chloride - in­

duced arrhythmia. The antiarrhythmic properties o f these com pounds in different m odels o f arrhythmia probably are related to their local anesthetic pro­

perties, but precise m echanism o f action o f those drugs to be further studied.

REFERENCES

1. Biilbring E., Wajda J.: J. Pharmacol. Exp. Ther.

85, 78 (1945).

2. Cam pbell S.F.: in Proceedings, X lV th Inter­

national Sym posium on M edicinal Chemistry.

F. A wouters ed„ 6 1 -7 0 , E lsevier, Amster- dam -Lausanne-N ew York-O xford-Shannon-To- kyo 1997.

3. Caterall W .A .: Trends Pharmacol. Sei. 8, 57 (1987).

4. Kato H., N oguchi Y ., Takagi K.: Jpn. J. Phar­

m acol. 24, 589 (1974).

5. Librowski T., Filipek B ., Czarnecki R., Beręse- w icz A., K arw atow ska-Prokopczuk E.: Acta Polon. Pharm. 55, 243 (1998).

6. Litchfield J.T., W ilcoxon F.: J. Pharmacol.

Exp. Ther. 96, 99 (1949).

7. M alaw ska B ., G orczyca M ., F ilipek B.: Pol. J.

Pharmacol. Pharm. 44, 561 (1992).

8. M itsuhashi H., A kiyam a K., H asim oto K., Saw a Y ., Hatori Y.: Japan J. Pharmacol 44,

155 (1987).

9. Monk J.P., Brogden R.N.: Drugs 40, 374 (1990).

10. Parmley W .W ., Braunwald E.: J. Pharmacol.

Exp. Ther. 168, 11 (1967).

11. Schuster D .P., L ucchesi B .R ., N obel N .L., M im naugh M .N ., C ounsell R .E., Frank J.K.: J.

Pharmacol. Exp. Ther. 184, 213 (1973).

12. Siem ieniuk A ., S załk ow sk a-P ągow sk a H., Lo- chyński S., Piątkowski K., Filipek B., Krupińs­

ka J., Czarnecki R., Librowski T., Białas S.:

Pol. J. Pharmacol. Pharm. 44, 575 (1992).

13. Szekeres L., Papp J.G.: in Handbook o f e x ­ perimental pharm acology (Ed. J. Schm ier and O. Eichler), Springer-V erlag, B erlin -H eid el- b erg -N ew York 1975.

14. Van Gelder I.C., Brugemann J., Crijns H.J.G.M.: Drugs 55, 331 (1998).

15. V aughan-W illiam s E.M.: in Anti-arrhythmic ac­

tion and the puzzle o f perhexiline (Ed. W.E.M.

Vaughan), Academic Press, London 1980.

R eceived: 3 .1 1 .1 9 9 9