Anti-arrhythmic composition and methods of treatment

Pharmaceutical compositions for the treatment of cardiac arrhythmia comprising an effective anti-arrhythmic amount of at least one compound in association with a pharmaceutically acceptable, substantially non-toxic carrier or excipient, the compound having one of the formulae (I) or (II) or a salt thereof with a pharmaceutically acceptable acid, and methods for the treatment of cardiac arrhythmia or effecting anti-arrhythmic action which comprise administering to a patient requiring anti-arrhythmic therapy or effect at least one of the above-described compounds.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to novel anti-arrhythmic compositions and 
methods of treating cardiac arrhythmia wherein the active anti-arrhythmic 
agent is one of several classes of polyamines and certain derivatives 
thereof. 
2. Description of the Prior Art 
Cardiac arrhythmias are disorders involving the electrical impulse 
generating system of the heart. The disorders include premature 
contractions (extrasystoles) originating in abnormal foci in atria or 
ventricles, paroxysmal supraventricular tachycardia, atrial flutter, 
atrial fibrillation, ventricular fibrillation and ventricular tachycardia 
[Goodman et al, eds., The Pharmacological Basis of Therapeutics, Sixth 
Edition, New York, MacMillan Publishing Co., pages 761-767 (1980)]. More 
particularly, cardiac arrhythmia is a disorder of rate, rhythm or 
conduction of electrical impulses within the heart. It is often associated 
with coronary artery diseases, e.g., myocardial infarction and 
atherosclerotic heart disease. Arrhythmia can eventually cause a decrease 
of mechanical efficiency of the heart, reducing cardiac output. As a 
result, arrhythmia can have life-threatening effects that require 
immediate intervention. 
Anti-arrhythmic drugs are commonly divided into four classes according to 
their electro-physiological mode of action. See Edvardsson, Current 
Therapeutic Research, Vol. 28, No. 1 Supplement, pages 113S-118S (July 
1980); and Keefe et al, Drugs, Vol. 22, pages 363-400 (1981) for 
background information of classification first proposed by Vaughn-Williams 
[Classification of Anti-Arrhythmic Drugs in Symposium of Cardiac 
Arrhythmias, pages 449-472, Sandoe et al, (eds.) A. B. Astra, Soederlalje, 
Sweden (1970)]. 
The classification of anti-arrhythmic drugs is as follows: 
I. Local anesthetic effect 
II. Beta-receptor blockade 
III. Prolongation of action potential duration 
IV. Calcium antagonism. 
Class I agents usually have little or no effect on action potential 
duration and exert local anesthetic activity directly at cardiac cell 
membrane. Class II agents show little or no effect on the action potential 
and exert their effects through competitive inhibition of beta-adrenergic 
receptor sites, thereby reducing sympathetic excitation of the heart. 
Class III agents are characterized by their ability to lengthen the action 
potential duration, thereby preventing or ameliorating arrhythmias. Class 
IV agents are those which have an anti-arrhythmic effect due to their 
actions as calcium antagonists. 
Class I: Sodium Channel Depressors 
These agents are efficacious in repressing a sodium current. However, these 
agents have no or only minute effects on the retention time of the normal 
action potential and decrease the maximum rising velocity (V.sub.max) of 
the sodium current. They exert anti-arrhythmic activity but at the same 
time strongly repress cardiac functions. Careful consideration is required 
in administering to patients with cardiac failure or hypotension. 
Class II: Beta-Blocking Agents 
The agents in this class, represented by propranolol, are efficacious in 
the beta-blocking action and are useful in treating patients with 
arrhythmia in which the sympathetic nerve is involved. However, care must 
be taken in their use since these agents have side effects caused by the 
beta-blocking action, such as depression of cardiac functions, induction 
of bronchial asthmatic attack and hypoglycemic seizures. 
Class III: Pharmaceutical Agents for Prolonging the Retention Time of the 
Action Current 
These agents are efficacious in remarkably prolonging the retention time of 
the action current of the cardiac muscle and in prolonging an effective 
refractory period. Re-entry arrhythmia is considered to be suppressed by 
the action of the pharmaceutical agents of Class III. The medicaments of 
this Class III include amiodarone and bretylium. However, all the agents 
have severe side effects; therefore, careful consideration is required for 
use. 
Class IV: Calcium Antagonists 
These agents control a calcium channel and suppress arrhythmia due to 
automatic sthenia of sinoatrial nodes and to ventricular tachycardia in 
which atrial nodes are contained in the re-entry cycle. 
Although various anti-arrhythmic agents within the above classes are now 
available on the market, those having both satisfactory effects and high 
safety have not been obtained. For example, anti-arrhythmic agents of 
Class I which cause a selective inhibition of the maximum velocity of the 
upstroke of the action potential (V.sub.max) are inadequate for preventing 
ventricular fibrillation. In addition, they have problems regarding 
safety, namely, they cause a depression of the myocardial contractility 
and have a tendency to induce arrhythmias due to an inhibition of the 
impulse conduction. Beta-adrenoceptor blockers and calcium antagonists 
which belong to Classes II and IV, respectively, have the defect that 
their effects are either limited to a certain type of arrhythmia or are 
contraindicated because of their cardiac depressant properties in certain 
patients with cardiovascular disease. Their safety, however, is higher 
than that of the anti-arrhythmic agents of Class I. 
Anti-arrhythmic agents of Class III are drugs which cause a selective 
prolongation of the duration of the action potential without a significant 
depression of the V.sub.max. Drugs in this class are limited. Examples 
such as sotalol and amiodarone have been shown to possess Class III 
properties. Sotalol also possesses Class II effects which may cause 
cardiac depression and are contraindicated in certain susceptible 
patients. Also, amiodarone is severely limited by side effects. Drugs of 
this class are expected to be effective in preventing ventricular 
fibrillations. Pure Class III agents, by definition, are not considered to 
cause myocardial depression or an induction of arrhythmias due to the 
inhibition of the action potential conduction as seen with Class I 
anti-arrhythmic agents. 
A number of anti-arrhythmic agents have been reported in the literature, 
such as those disclosed in EP 397,121; EP 300,908; EP 307,121; U.S. Pat. 
No. 4,629,739; U.S. Pat. No. 4,544,654; U.S. Pat. No. 4,788,196; EP 
application 88 302 597.5; EP application 88 302 598.3; EP application 88 
302 270.9; EP application 88 302 600.7; EP application 88 302 599.1; EP 
application 88 300 962.3; EP application 235,752; DE 36 33 977; U.S. Pat. 
No. 4,804,662; U.S. Pat. No. 4,797,401; U.S. Pat. No. 4,806,555; and U.S. 
Pat. No. 4,806,536. 
It is an object of the present invention to provide novel anti-arrhythmic 
pharmaceutical compositions and methods of treating cardiac arrhythmia 
wherein the effective anti-arrhythmic agent functions according to a 
mechanism substantively different from that of any of the above-described 
four classes of anti-arrhythmic agents. The compositions and methods of 
treatment of the present invention are not, therefore, subject to the 
above-noted disadvantages associated with the known four classes of 
anti-arrhythmic agents. 
SUMMARY OF THE INVENTION 
The present invention provides novel pharmaceutical compositions in unit 
dosage form for the treatment of cardiac arrhythmia comprising an 
effective anti-arrhythmic amount of at least one compound in association 
with a pharmaceutically acceptable, substantially non-toxic carrier or 
excipient; the compound having one of the formulae: 
##STR1## 
or 
##STR2## 
wherein: R and R' may be the same or different and are H, alkyl, 
fluoroalkyl or aralkyl having from 1 to 12 carbon atoms; 
R.sub.1 -R.sub.4 may be the same or different and are H, R or R'; 
m and n may be the same or different and are integers from 2 to 10, 
inclusive; and 
x, y and z may be the same or different and are integers from 0 to 8, 
inclusive; 
or 
(III) a salt of (I) or (II) with a pharmaceutically acceptable acid. 
The invention also provides a novel method for the treatment of cardiac 
arrhythmia and related heart problems or effecting anti-arrhythmic action 
which comprises administering to a patient requiring anti-arrhythmic 
therapy an anti-arrhythmic effective amount of at least one of the 
above-described compounds. 
DETAILED DESCRIPTION OF THE INVENTION 
The present invention is predicated on the discovery that the 
above-described polyamines (or suitable salts thereof) exert an 
anti-arrhythmic effect when administered to a patient in need of an 
anti-arrhythmic effect. 
Suitable polyamines for use in the composition and methods of the present 
invention having the formulae (I) and (II) above, as well as derivatives 
and salts thereof (III) are those described in U.S. Pat. No. 5,091,576, 
the entire contents and disclosures of which are incorporated herein by 
reference. Methods for the preparation of the polyamines are also 
disclosed therein. 
In compounds of formulae (I) and (II), R and R' are preferably methyl, 
ethyl, propyl, benzyl, CF.sub.3 CH.sub.2 --, etc., it being understood 
that the term "aralkyl" is intended to embrace any aromatic group the 
chemical and physical properties of which do not adversely affect the 
efficacy and safety of the compound for therapeutic applications. 
Preferred, however, are the hydrocarbyl aralkyl groups, i.e., comprised 
only of c and H atoms. 
R.sub.1 -R.sub.4 preferably are H, methyl, ethyl, propyl or benzyl. 
Preferred polyamines of formula (I) are those wherein (a) m is 3 and n is 
4; (b) both m and n are 4; (c) R and R' are alkyl, such as methyl, ethyl 
and propyl; (d) R and R' are aralkyl, such as benzyl; and (e) R and R' are 
fluoroalkyl, such as CF.sub.3 CH.sub.2 --. 
It will be appreciated that while the agents described above form acid 
addition salts and carboxy acid salts, the biological activity thereof 
will reside in the agent itself. These salts may be used in human medicine 
and presented as pharmaceutical formulations in the manner and in the 
amounts (calculated as the base) described herein, and it is then 
preferable that the acid moiety be pharmacologically and pharmaceutically 
acceptable to the recipient. Examples of such suitable acids include (a) 
mineral acids, i.e., hydrochloric, hydrobromic, phosphoric, metaphosphoric 
and sulfuric acids; (b) organic acids, i.e., tartaric, acetic, citric, 
malic, maleic, lactic, fumaric, benzoic, glycolic, gluconic, gulonic, 
succinic and aryl-sulfonic acids, e.g., p-toluene-sulfonic acid. 
The compounds of the present invention are effective in treating and 
preventing all types of arrhythmias including ventricular and atrial 
(supraventricular) arrhythmias and associated fibrillations. 
In the novel method of this invention of treating arrhythmia, a novel 
compound or pharmaceutically acceptable salt thereof is administered in an 
amount ranging from about 0.1 to about 300 mg/kg of body weight, 
preferably from about 0.1 to about 50 mg/kg of body weight, in a single 
dose, in divided doses or by intravenous infusion. 
The polyamines of this invention can be administered as the sole active 
ingredient or in combination with other anti-arrhythmic agents or other 
cardiovascular agents. 
The polyamines or pharmaceutically acceptable salts thereof of the present 
invention in the described dosages are administered orally, 
intraperitoneally, subcutaneously, intramuscularly, transdermally, 
sublingually or intravenously. 
They are preferably administered orally, for example, in the form of 
tablets, troches, capsules, elixirs, suspensions, syrups, wafers, chewing 
gum or the like prepared by art recognized procedures. The amount of 
active compound in such therapeutically useful compositions or 
preparations is such that a suitable dosage will be obtained. 
The pharmaceutical compositions of the invention preferably contain a 
pharmaceutically acceptable carrier or excipient suitable for rendering 
the compound or mixture administrable orally as a tablet, capsule or pill, 
or parenterally, intravenously, intradermally, intramuscularly or 
subcutaneously, rectally, via inhalation or via buccal administration, or 
transdermally. The active ingredients may be admixed or compounded with 
any conventional, pharmaceutically acceptable carrier or excipient. It 
will be understood by those skilled in the art that any mode of 
administration, vehicle or carrier conventionally employed and which is 
inert with respect to the active agent may be utilized for preparing and 
administering the pharmaceutical compositions of the present invention. 
Illustrative of such methods, vehicles and carriers are those described, 
for example, in Remington's Pharmaceutical Sciences, 4th ed. (1970), the 
disclosure of which is incorporated herein by reference. Those skilled in 
the art, having been exposed to the principles of the invention, will 
experience no difficulty in determining suitable and appropriate vehicles, 
excipients and carriers or in compounding the active ingredients therewith 
to form the pharmaceutical compositions of the invention. 
The therapeutically effective amount of active agent to be included in the 
pharmaceutical composition of the invention depends, in each case, upon 
several factors, e.g., the type, size and condition of the patient to be 
treated, the intended mode of administration, the capacity of the patient 
to incorporate the intended dosage form, etc. 
While it is possible for the agents to be administered as the raw 
substances, it is preferable, in view of their potency, to present them as 
a pharmaceutical formulation. The formulations of the present invention 
for human use comprise the agent, together with one or more acceptable 
carriers therefor and optionally other therapeutic ingredients. The 
carrier(s) must be "acceptable" in the sense of being compatible with the 
other ingredients of the formulation and not deleterious to the recipient 
thereof. Desirably, the formulations should not include oxidizing agents 
and other substances with which the agents are known to be incompatible. 
The formulations may conveniently be presented in unit dosage form and may 
be prepared by any of the methods well known in the art of pharmacy. All 
methods include the step of bringing into association the agent with the 
carrier which constitutes one or more accessory ingredients. In general, 
the formulations are prepared by uniformly and intimately bringing into 
association the agent with the carrier(s) and then, if necessary, dividing 
the product into unit dosages thereof. 
Formulations suitable for parenteral administration conveniently comprise 
sterile aqueous preparations of the agents which are preferably isotonic 
with the blood of the recipient. Suitable such carrier solutions include 
phosphate buffered saline, saline, water, lactated ringers or dextrose (5% 
in water). Such formulations may be conveniently prepared by admixing the 
agent with water to produce a solution or suspension which is filled into 
a sterile container and sealed against bacterial contamination. 
Preferably, sterile materials are used under aseptic manufacturing 
conditions to avoid the need for terminal sterilization. 
Such formulations may optionally contain one or more additional ingredients 
among which may be mentioned preservatives, such as methyl 
hydroxybenzoate, chlorocresol, metacresol, phenol and benzalkonium 
chloride. Such materials are of special value when the formulations are 
presented in multidose containers. 
Buffers may also be included to provide a suitable pH value for the 
formulation. Suitable such materials include sodium phosphate and acetate. 
Sodium chloride or glycerin may be used to render a formulation isotonic 
with the blood. If desired, the formulation may be filled into the 
containers under an inert atmosphere such as nitrogen or may contain an 
anti-oxidant, and are conveniently presented in unit dose or multi-dose 
form, for example, in a sealed ampoule. 
Those skilled in the art will be aware that the amounts of the various 
components of the compositions of the invention to be administered in 
accordance with the method of the invention to a patient will depend upon 
those factors noted above. 
The compositions of the invention when given orally or via buccal 
administration may be formulated as syrups, tablets, capsules and 
lozenges. A syrup formulation will generally consist of a suspension or 
solution of the compound or salt in a liquid carrier, for example, 
ethanol, glycerine or water, with a flavoring or coloring agent. Where the 
composition is in the form of a tablet, any pharmaceutical carrier 
routinely used for preparing solid formulations may be employed. Examples 
of such carriers include magnesium stearate, starch, lactose and sucrose. 
Where the composition is in the form of a capsule, any routine 
encapsulation is suitable, for example, using the aforementioned carriers 
in a hard gelatin capsule shell. Where the composition is in the form of a 
soft gelatin shell capsule, any pharmaceutical carrier routinely use for 
preparing dispersions or suspensions may be considered, for example, 
aqueous gums, celluloses, silicates or oils, and are incorporated in a 
soft gelatin capsule shell. 
A typical suppository formulation comprises the polyamine or a 
pharmaceutically acceptable salt thereof which is active when administered 
in this way, with a binding and/or lubricating agent, for example, 
polymeric glycols, gelatins, cocoa-butter or other low melting vegetable 
waxes or fats. 
Typical transdermal formulations comprise a conventional aqueous or 
non-aqueous vehicle, for example, a cream, ointment, lotion or paste or 
are in the form of a medicated plastic, patch or membrane. 
Typical compositions for inhalation are in the form of a solution, 
suspension or emulsion that may be administered in the form of an aerosol 
using a conventional propellant such as dichlorodifluoromethane or 
trichlorofluoromethane. 
The compositions of the present invention may be co-administered with other 
pharmaceutically active compounds, for example, in combination 
concurrently or sequentially. Conveniently, the compound of this invention 
and the other active compound or compounds are formulated in a 
pharmaceutical composition. Examples of compounds which may be included in 
pharmaceutical compositions with the polyamines of the invention include 
vasodilators, for example, hydralazine; angiotensin converting enzyme 
inhibitors, for example, captopril; anti-anginal agents, for example, 
isosorbide nitrate, glyceryl trinitrate and pentaerythritol tetranitrate; 
anti-arrhythmic agents, for example, quinidine, procainamide and 
lignocaine; cardioglycosides, for example, digoxin and digitoxin; calcium 
antagonists, for example, verapamil and nifedipine; diuretics, such as 
thiazides and related compounds, for example, bendrofluazide, 
chlorothiazide, chlorothalidone, hydrochlorothiazide and other diuretics, 
for example, fursemide and triamterene, and sedatives, for example, 
nitrazepam, flurazepam and diazepam.

The invention is illustrated by the following non-limiting examples. 
EXAMPLE 1 
Isoproterenol is known to induce arrhythmias in mammals when administered 
thereto in large doses. The following tests were carried out to ascertain 
the efficacy of the above-described polyamines in preventing 
isoproterenol-induced arrhythmias and deaths. 
Desoxycorticosterone acetate, d,l-propranolol and isoproterenol were 
obtained commercially. The polyamine analogues were synthesized as 
described in U.S. Pat. No. 5,091,576 and put into solution with sterile 
normal saline. 
The drug solutions were made fresh for each experiment. 
Male Wistar rats (275-300 g) were obtained from Charles River laboratories 
(Wilmington, MA). The animals were housed in a temperature- and 
humidity-controlled room. This investigation conforms with the Guide for 
the Care and Use of Laboratory Animals published by the U.S. National 
Institutes of Health (NIH Publication No. 85-23, revised 1985). 
Briefly, rats were anesthetized with sodium pentobarbital (55 mg/kg. i.p.), 
and a 25 mg pellet of desoxycorticosterone acetate (DOCA) was implanted 
s.c. in the axillary region. The rats were allowed to recover from the 
anesthetic and returned to their home cages. The animals were given 
commercial rat chow and a 1% solution of saline as their drinking fluid ad 
libitum. The animals were maintained on this regimen for approximately 
thirty days. After this time, the animals were weighed and randomly 
assigned to one of three treatment protocols: (1) the identification of 
anti-arrhythmic agents and a dose response of the effective compounds 
(Section A hereinbelow); (2) arrhythmia prevention studies including 
electrocardiogram (EKG), blood pressure and heart rate determinations 
(Section B hereinbelow); and (3) the induction and reversal of an 
established arrhythmia (Section C hereinbelow). 
A. Testing of polyamine analogues for anti-arrhythmic properties 
In order to identify compounds with anti-arrhythmic properties suitable for 
further study, unrestrained, conscious rats were weighed, placed in 
individual cages and given a s.c. injection of either a positive control 
(d,l-propranolol, 1 mg/kg), a negative control (saline placebo) or a 
polyamine analogue. Twenty minutes later, the rats were challenged with a 
single s.c. dose of isoproterenol, 150 .mu.g/kg. The animals were closely 
monitored for one hour and any obvious arrhythmic episodes or mortalities 
were recorded. A dose response was performed on compounds displaying 
anti-arrhythmic properties. 
B. Evaluation of blood pressure, heart rate and EKG 
Blood pressure and heart rate parameters, as well as an EKG, were evaluated 
for compounds displaying anti-arrhythmic properties. The animals were 
implanted with DOCA and maintained on 1% saline as their drinking fluid as 
discussed above. The animals were anesthetized with Avertin 
(tribromoethanol, 2.5%), 1 ml/100 g given i.p. and prepared for the 
recording of blood pressure and the EKG. To allow for the direct 
measurement of blood pressure, the animals's left carotid artery was 
cannulated with PE-50 tubing. The tubing was filled with saline and 
exteriorized dorsally between the animal's shoulders. 
After the surgery was completed, the catheter in the carotid artery was 
connected to a blood pressure transducer (ADInstruments, Inc., Milford, 
Mass.). To allow for the recording of the EKG, 22 gauge needles were 
placed s.c. at the rat's left shoulder, right shoulder and left leg. The 
needles were then attached via alligator clips to a MacLab Bio Amplifier 
(ADInstruments, Inc., Milford, Mass.). The blood pressure transducer and 
the MacLab Bio Amplifier were, in turn, connected to a MacBridge 4 
(ADInstruments, Inc., Milford, Mass.), a computer-controlled transducer 
interface. The data were then transmitted to the MacLab 4e data 
acquisition system powered by a Macintosh Quadra 650. The MacLab Chart 
program was used to display and analyze the data. A baseline blood 
pressure, heart rate and EKG were obtained, and the compound under 
investigation was administered s.c. Twenty minutes later, the animals were 
challenged with a single dose of isoproterenol, 150 .mu.g/kg s.c. 
Continuous blood pressure, heart rate and EKG readings were obtained. 
Additional Avertin was given as needed to maintain anesthesia. The hearts 
of the animals were perfused with buffered formalin immediately after the 
onset of ventricular fibrillation or one hour after the administration of 
the isoproterenol. 
C. Arrhythmic reversal studies 
The animals were implanted with a 25 mg pellet of DOCA and maintained on 
the 1% saline as their drinking fluid as discussed above. The animals were 
anesthetized with Avertin and prepared for the recording of blood pressure 
and the EKG. In addition, the animal's left jugular vein was also 
cannulated with PE-50 tubing. The tubings were filled with saline and 
exteriorized dorsally between the animal's shoulders. Isoproterenol was 
administered s.c. at a dose of 150 .mu.g/kg and an arrhythmia was allowed 
to develop for five minutes. After this time, either propranolol or the 
compound of interest was given as an intravenous bolus at one-half of the 
effective s.c. dose. Continuous blood pressure, heart rate and EKG 
readings were obtained. Additional Avertin was given as needed to maintain 
anesthesia. The hearts of the animals were perfused with buffered formalin 
immediately after the onset of ventricular fibrillation or one hour after 
the administration of isoproterenol. 
The data are presented as the mean .+-. s.e.m. Statistical analyses of the 
data were performed by use of the Student's t-test. A value of P&lt;0.05 was 
considered significant. 
Two kinds of anti-arrhythmic experiments were carried out, both prophylaxis 
and reversal studies. DOCA-treated animals were either first given the 
test compounds s.c. followed twenty minutes later by isoproterenol 
(prevention studies) or isoproterenol followed by the test compound given 
intravenously after five minutes (reversal studies). The time frames were 
chosen based on two issues: previous experience with the pharmacokinetics 
of polyamine analogues and the time required for isoproterenol to induce 
cardiac abnormalities and death in DOCA-treated rodents. 
Within the boundary conditions of these studies, 95% of all 
DOCA/isoproterenol-treated controls were dead within one hour and abnormal 
cardiac electrical events usually began within five minutes which is in 
keeping with reports in the literature. Propranolol served as the positive 
control in both the prophylactic and reversal experiments. In order to 
compare the compounds, all dosages are recorded in both mg/kg and 
.mu.mol/kg. Finally, the reversal studies only focus on the most effective 
prophylactic device PYR(3,3,3). 
Under these experimental conditions, propranolol was clearly the more 
effective prophylactic and reversal device from a dosage perspective. 
Beyond this, the behavior of the polyamines was rather varied. 
Surprisingly, putrescine had no effect on survival in this system, even at 
concentrations higher than those reported in the earlier aconitine and 
reperfusion arrhythmia models. 
As described above, all three of the tetraamines DENSPM, DESPM and DEHSPM 
are very potent polyamine anti-metabolites; all three are tetracations at 
physiologic pH. Interestingly, none of the three polyamine 
anti-metabolites tested in this model had any effects on the survival of 
DOCA/isoproterenol-treated rats. PIP(3,3,3), a cyclic aliphatic 
tetraamine, is largely a trication at physiologic pH; this compound was 
not an effective polyamine anti-metabolite, nor was it found to be active 
in this model. 
The remainder of the compounds investigated were all largely dications at 
physiological pH. FDESPM, a molecule of very similar geometry to DESPM, 
did indeed show some anti-arrhythmic prophylactic behavior with 40% of the 
animals surviving. This dicationic tetraamine has both charges at the two 
central nitrogens. When the charges are moved farther apart as in DE(9), 
the compound has no activity. 
Of the pyridine tetraamines investigated, PYR(3,3,3), PYR(3,4,3) and 
PYR(4,4,4) all presented with anti-arrhythmic properties. The two most 
active compounds, PYR(3,3,3) and PYR(3,4,3), demonstrated a clear dose 
response. Because of the minimal activity of the PYR(4,4,4) system, a 
dose-response study was not run. 
In light of earlier results indicating that both DEHSPM and DENSPM lower 
blood pressure in normotensive rats, continuous monitoring of blood 
pressure and heart rate was performed on animals treated with propranolol 
and PYR(3,3,3). No appreciable effects on blood pressure and heart rate 
were observed in rats treated with PYR(3,3,3). 
From a prevention perspective, PYR(3,3,3) performed best. PYR(3,3,3) was 
also evaluated in reversal experiments. DOCA-treated animals were given 
isoproterenol and allowed to enter an arrhythmic event. Isoproterenol 
given intravenously in these animals induces an event within one minute. 
The animals were then treated with saline, propranolol or PYR(3,3,3) five 
minutes after isoproterenol. Animals given saline quickly died of 
ventricular fibrillation; animals treated with propranolol not only 
survived, but also had EKG's that reverted to a more normal pattern. 
However, there was some evidence of ischemia. In contrast, the EKG's in 
animals given PYR(3,3,3) reverted to a normal appearance and showed little 
to no evidence of ischemia. 
The above-discussed results are presented in the following table. 
TABLE 
______________________________________ 
EFFECT OF POLYAMINE ANALOGUES ON THE INCIDENCE 
OF MORTALITY PRODUCED BY ISOPROTERENOL 
IN DOCA/SALINE PRE-TREATED RATS 
ARRHYTH- % SUR- 
TREATMENT 
(MG/KG) 
(.mu.MOL/KG) 
N = MIA VIVAL 
______________________________________ 
Control 
-- -- 20 20 5 
Propranolol 
1 3.4 
0 
100 
DENSPM 90.27 
231 5 
0 
(3,3,3) 
DESPM (3,4,3) 
46.7 
115 
5 
0 
DEHSPM 50 115 
5 
0 
(4,4,4) 
PIP (3,3,3) 
44.6 
115 
5 
0 
Putrescine (4) 
18.6 115 
5 
0 
200 
1240 
5 
0 
300 
1861 
5 
0 
DE (9) 33.2 
115 
5 
0 
FDESPM 59.1 
115 
40 
PYR (3,3,3) 
4.38 
14 5 
40 
28 5 
40 
59 
4 
60 
115 
2 
100 
PYR (3,4,3) 
18.2 
59 
2 
60 
115 
2 
60 
231 
2 
80 
PYR (4,4,4) 
48 115 
5 
0 
231 
2 
40 
PYR (5,4,5) 
51.6 
115 
5 
0 
______________________________________ 
DEHSPM (4,4,4) = diethylhomospermine 
DENSPM (3,3,3) = diethylnorspermine 
DESPM (3,4,3) = diethylspermine 
##STR3## 
- 
##STR4## 
- 
##STR5## 
- 
PYR (4,4,4) =- 
##STR6## 
- 
PYR (5,4,5) =- 
##STR7## 
- 
FDESPM (3,4,3) = Di.beta.,.beta.,.beta.-trifluoroethylspermine 
DE (9) = C.sub.2 H.sub.5 --NH--(CH.sub.2).sub.9 --NH--C.sub.2 H.sub.5 - 
EXAMPLE 2 
In this procedure [Lawson, J. Pharmacol. Exper. Therap., Vol. 160, pages 
22-31 (1968)], the test substance [diethylhomospermine (DEHSPM)] is 
administered i.p. (100 mg/kg) to a group of three mice thirty minutes 
before exposure to deep chloroform anesthesia and observed during the 
ensuing 15-minute period. Absence of EKG recorded cardiac arrhythmias and 
heart rates above 200 beats per minute present (usual=400-480 beats per 
minute) in none or only one (&lt;2) of three animals indicates significant 
protection. 
Only one animal exhibited cardiac arrhythmia, thereby demonstrating the 
anti-arrhythmic activity of DEHSPM.