Frederick Coulston

The biologic actions of a new series of bis(dichloroacetyl) diamines

Abstract Three members (Win 13,099, Win 17,416, Win 18,446) of a new series of bis(dichloroacetyl) diamines have been studied orally in rats, dogs, and/or monkeys. These data indicate the following points: 1. 1. These compounds proved to be relatively nontoxic substances which exert a specific effect upon the testes of the species studied. 2. 2. This biologic effect on the testes is characterized by arrest of spermatogenesis which is completely reversible within a few weeks after withdrawal of the drug. The Leydig, Sertoli, and spermatogonial cells appear to be normal even under the full influence of these drugs. 3. 3. The mechanism of the action of this phenomenon is not understood at present but should provide a fine tool in the study of the specific biochemical requirements for spermatogenesis.

Inhibition and recovery of spermatogenesis in rats monkeys and dogs medicated with bis(dichloroacetyl)diamines.

Abstract The antispermatogenic activity of three bis(dichloroacetyl)diamines, Win 13,099, Win 18,446, and Win 17,416, was studied in rats, monkeys and/or dogs. The drugs were administered orally and testicular tissue was obtained at various intervals by autopsy or biopsy. The data obtained from these experiments suggest the following conclusions: The three drugs, when given orally to adult male albino rats, monkeys, and dogs, resulted in arrest of spermatogenesis characterized by gradual depletion of the germinal cells of the testes. Full recovery occurred after withdrawal of medication even after antispermatogenic changes had had been in effect for long periods of time and the animals had become histologically azoospermic. The effect of these drugs upon the germinal epithelium was very specific; no other organs were affected. The histologic course of events observed resembled that seen with other agents except for this specificity. The formation of large multinucleated forms containing the nuclei of Golgi and cap-phase spermatids was a prominent characteristic of the inhibitory effects. The authors propose the term fusion bodies to describe these forms, and hope by this report to have resolved the confusion surrounding these forms. Although the antispermatogenic changes were basically similar in the rat, monkey, and dog there were marked differences in the minimal effective dose between the three compounds as well as with the same compound in different species of animals.

The pharmacology and toxicology of mepivacaine, a new local anesthetic.

Abstract The local anesthetic activity, toxicity, and irritancy of mepivacaine HCl 1 (1-methyl-2′,6′-pipecoloxylidide hydrochloride) and a solution (solution B) containing 2.0% mepivacaine HCl and 1:20,000 levo-nordefrin (levo-2,4-dihydroxyphenyl-3-hydroxy-2-isopropylamine 2 ) have been studied by various methods. By the intracutaneous wheal test in guinea pigs mepivacaine HCl is 2.5 times more active than procaine HCl. The addition of levo-nordefrin produced a slight increase in the local anesthetic activity of the solution. Solution B was found as active as a solution of 2.0% lidocaine + epinephrine 1:100,000 by the same route of administration ( dilution test ). At the 2.0% concentration level in solutions containing epinephrine 1:100,000 the duration of mepivacaine intradermal anesthesia was approximately 25% longer than that produced by lidocaine. Mepivacaine HCl was found to be as active as cocaine HCl by topical application to the rabbit eye. The topical TAC 5 was 0.18%. At 2, 3, 4, and 8% concentrations, mepivacaine HCl injected intraspinally in rabbits produced anesthesia lasting from 17 to 115 minutes (urethral anesthesia). The degree of intraspinal irritancy appears to be somewhat lower than that of lidocaine. By intravenous injection the following LD 50 values for mepivacaine HCl in mice, rabbits, and guinea pigs were obtained: 32±2, 22±2, and 20±1.4 mg/kg, respectively. Mepivacaine is approximately twice as toxic as procaine HCl and 40% less toxic than lidocaine HCl in mice. The subcutaneous LD 50 values were: 260±22, 110±11, and 94±10 mg/kg for mice, rabbits, and guinea pigs, respectively. Solution B and a 3% solution of mepivacaine HCl without levo-nordefrin (solution A) were well tolerated by monkeys and rats when injected intramuscularly or intravenously in single daily doses eighteen times in 21 days. No significant changes were observed in the body weights, blood counts, urinalyses, or blood pressures of the medicated animals at the end of the medication period. No changes attributable to medication with mepivacaine were observed at the autopsies of the medicated animals. By the trypan blue test the threshold irritant concentration 4 of mepivacaine HCl was 3.3%. That of lidocaine HCl, which was tested in parallel, was 1.9%. Lidocaine HCl is therefore approximately 70% more irritant than mepivacaine HCl. Applied topically on the rabbit eye, mepivacaine HCl and lidocaine HCl were well tolerated in concentrations up to 20%. Solution A and solution B produced a slight, transient inflammatory reaction when injected intramuscularly into rabbits in 1.0-cc doses. No lesions at the injection sites were observed at 7 days after the injection. In summary, mepivacaine HCl, which is 2.5 times more active than procaine HCl is only 25% more irritating and is well tolerated locally as well as systemically on repeated subcutaneous or intramuscular administration.

EFFECTS OF THALIDOMIDE ON FETAL DEVELOPMENT IN RABBITS AND ON ESTABLISHMENT OF PREGNANCY IN MONKEYS.

Abstract Medication with thalidomide (150.0 mg/kg) in pregnant New Zealand white rabbits resulted in a wide range of teratogenic changes in the kits. The most predominant effects were seen in the limbs (arthrogryposis, micromelia, absence of digits). When rhesus monkeys ( Macaca mulatta ) were fed thalidomide in the diet (150.0 mg/kg), interference with establishment of pregnancy occurred. No pregnancies were observed in the five medicated females while two unmedicated controls delivered normal young.

The pathologist and toxicologist in the evaluation of the safety and methods of development of radiodiagnostic compounds.

In searching for new X-ray contrast media, the pharmacologist, the chemist, the toxicologist, and the pathologist must work closely together as a research team. The work of the pharmacologist and chemist is fairly well understood; the one screens the chemical compounds made and submitted by the other. The role of the toxicologist and the pathologist in this team is not well understood. Their primary functions are to help in the selection of the best compound and to establish its safety prior to clinical investigation. Their studies usually include toxicity experiments comparing the new X-ray contrast media with each other and with commercially available products. Detailed gross and histological examinations of the tissues of animals often indicate which contrast medium is superior, even though several of them may have been equally good in terms of visualization. In addition, the pathologist can contribute his knowledge of the anatomy and histology of the various species of animals used in this kind of research. The toxicologist can sometimes determine the best chemical compound by carefully distinguishing between pharmacodynamic reactions resulting from injections of large doses of the new contrast media in the same and in different species of animals. In the following report, experiments will be presented indicative of the part the toxicologist and pathologist play in developing new X-ray contrast media.

Laboratory evaluation of a new contraceptive gel with trichomonadicidal and moniliastatic properties

Abstract 1. 1. A new contraceptive gel formulation was tested for its chemotherapeutic, toxicologic, and allergenic properties. 2. 2. The new gel was highly trichomonadicidal against Trichomonas vaginalis and T. gallinae by in vitro test methods. When hamsters were medicated with this gel intravaginally once daily for 5 days, they were completely cleared of T. gallinae which had been established experimentally in the vagina. 3. 3. The gel possessed fungistatic activity against Candida albicans. 4. 4. The gel was not irritating when topically applied to the abraded skin of rabbits. It produced no vaginal irritation or alteration in mucosal architecture or secretions when introduced into the vagina of monkeys three times weekly for 41 weeks. 5. 5. The gel was not allergenic in rabbits when animals were injected intradermally 2 weeks after the last of a series of “sensitizing” doses. 6. 6. Eleven volunteers who liberally applied the gel to penile surfaces for 8 hours or longer observed no irritation of any kind. 7. 7. The new gel combines in a highly effective spermatocidal formulation, antiseptic, surfactant, osmotic, and lytic properties with the barrier actions of conventional tragacanth, gel, and cream formulas.

Comparison of parenterally administered calcium kinate gluconate with calcium gluconate and calcium chloride.

Abstract The pharmacologic and toxic properties of calcium kinate gluconate, calcium gluconate, and calcium chloride have been studied in mice, dogs, and monkeys. The pharmacologic properties appeared to be based on the calcium concentration except for acute intravenous tolerance where calcium kinate gluconate was better tolerated than calcium gluconate. Calcium kinate gluconate and calcium gluconate injections produced transient decrease in blood clotting time, but increased platelet counts were observed only following calcium kinate gluconate injections. The calcium kinate gluconate effect on blood probably was attributable to the presence of calcium and kinic acid. No toxic properties of calcium kinate gluconate and calcium gluconate were observed in a 6-month tolerance study in dogs. Good clinical tolerance of calcium kinate gluconate was reported on over 200 cases.

A laboratory evaluation of the effect of the coccidiostat, trithiadol on the growth of chickens.

In feeding trials with chicks through 9 weeks, replicated groups fed 0.1% dietary Trithiadol®-supplemented feed gained weight as well as did the control groups, while the weight gains of those fed 0.0125% dietary nicarbazin-supplemented feed were affected adversely. The chicks in all the groups exhibited no adverse effects by any of the other criteria used, including feed conversions and physical characteristics of the birds through dressing out. In a second feeding trial in which the anticoccidial agents were fed at the commercially recommended level and at three to six times this level, there was no apparent effect on the weight gains in the use level-fed replicated groups. The birds fed the threefold nicarbazin-supplemented feed weighed significantly less than those of the control group (P = <0.001). The chicks fed the sixfold level of Trithiadol-supplemented feed also weighed less than the birds of the control group (P = 0.02). None of the chicks exhibited any other adverse effect. The results from these laboratory feeding trials support the view that Trithiadol may be expected to exhibit a wide margin of safety under conditions of use.

Pharmacologic and toxicologic studies of two new centrally acting skeletal muscle relaxants, chlormethazanone and dichlormethazanone☆☆☆

Abstract 1. 1. 2-(4-Chlorophenyl)-3-methyl-4-metathiazanone-1-dioxide (Win 4692, chlormethazanone) and its 3,4-dichlorophenyl analog (Win 12,267, dichlormethazanone) produced an ascending type of paralysis associated with a marked ataxia in all species tested. At ataxic dose levels, Win 12,267 caused a marked hyperreflexia in the larger species (cat and monkey). Such effects were not seen with Win 4692 at sublethal dose levels. 2. 2. Both Win 4692 and Win 12,267 were found to be more active than meprobamate in various CNS effects as follows: Both Win 4692 and Win 12,267 intensified the depressant action of either pentobarbital or ethyl alcohol in mice. Both compounds inhibited the crossed extensor reflex of the spinal cat without affecting the monosynaptic (knee jerk) reflex. Both compounds produced EEG slowing and spindling, and blocked “EEG arousal” in the unanesthetized rabbit. 3. 3. Win 4692 was found to be devoid of analgesic properties in the rat at sublethal dose levels. No significant autonomic or smooth muscle effects could be demonstrated. 4. 4. The acute oral and intraperitoneal median lethal doses of Win 4692 and Win 12,267 in several species varied from about 400.0 to 1400.0 mg/kg and from about 300.0 to 1050.0 mg/kg, respectively. 5. 5. The daily administration of sublethal doses of either Win 4692 or Win 12,267 to albino rats for 5 consecutive days produced only an initial loss of weight. No significant hematologic alteration or macroscopic lesion of any of the viscera, attributable to medication with either drug, was observed. 6. 6. The results of a one-year chronic toxicity study in monkeys indicate that Win 4692, in doses of 10.0, 30.0, and 90.0 mg/kg per day, and Win 12,267, in doses of 5.0, 15.0, and 45.0 mg/kg per day, were well tolerated. The chief pharmacologic response observed was ataxia. The growth rates of all medicated groups were less than those of the controls, but these differences were not considered to be significant. Hematologic and histologic studies and urinalyses revealed no significant alteration or lesion attributable to medication.

Toxicology and spermicidal activity of a new contraceptive cream containing chlorindanol and laureth 9

Abstract Lanettes® is a new contraceptive aerosol cream formulation containing two spermicidal ingredients: 7-chloro-4-indanol, and laureth 9, a polyoxyethylene lauryl ether. The aerosol cream was tested by three recognized spermicidal test procedures and was found to be a highly spermicidal preparation. Spermatozoa were immobilized in less than 20 seconds even after a 100-fold dilution. This preparation is a nongreasy, nonsoapy, nonstaining preparation and has moniliastatic and trichomonacidal properties. The individual dose units are so designed that the entire contents of the glass vial can be deposited in the vaginal vault. Expansion occurs in the vagina rather than in the dispenser, and the foam coats the vaginal walls and the streaming mucus and blocks a normally positioned cervical os. The aerosol cream was nonirritating to vaginal and cervical mucosae of beagle dogs when deposited 79 times in 183 days and it failed to adversely affect the animals in any way. Thirteen male volunteers repeatedly applied liberal amounts of the aerosol cream to penile surfaces for 8 hours or longer, four times a week for 2 weeks, and observed no ill effects. A challenge application 2 weeks later failed to elicit sensitization.