ORAL CONTRACEPTIVE-PART III FURTHER OBSERVATIONS ON THE ANTIFERTILITY EFFECT OF ROTTLERIN By D. R. VARMA, K. N. SAREEN, A. K. ROY AND M. L. GUJRAL Frm the Department f Pharmaclgy, K. G. Medical Cllege, Lucknw University. ( Received n April 28, 199 ). The antifertility effect f Malltus philippinensis in rats and guineapigs has been reprted by Gujral and cwrkers (199 a). In a further study Gujral et ai. (199 b) reprted the effects f varius chemical cnstituents and fractins f this plant n the fertility rate f female rats. As the antifertility effect f the plant was shwn by these wrkers t be due t the presence f rttlerin in it, it was thught desirable t study this active principle in greater detail. The present cmmunicatin includes investigatins f certain ther effects f rttlerin. METHODS AND MATERIALS The experiments were cnducted in albin rats belnging t the clny f Central Drug Research Institute, Lucknw. The animals were given standard diet as reprted previusly (Gujral et ai., 199 a). Rttlerin was made int an emulsin and fed in the required dses by ral cannula. Oestrus cycle.-ten adult female rats shwing regular estrus cycle were selected fr the experiment. The vaginal smears were taken daily fr 1 days preceeding the drug treatment and fr the subsequent perid fl days f the drug administratin. Thus the same rats served as their cntrl. The smears were stained with Wright's stain and criterin used fr determining the stages f estrus cycle was the same as described by Allen (1922). Effect n fertility when given in varius stages f the estrus cycle.-previusly tested fertile rats were used in. this set f experiments. Animals were divided in fur grups each cntaining five rats. Grup I-The drug was given the stage f estrus nly and the rat was chabitated with a male.
I VARMA, SAREEN, ROY AND OUJRAL 169 Grup II-The drug was given n the day f prestrus nly and chabitated. Grup III-The drug was given fr a perid f 6 days after the mating. Grup IV-The drug was given diestrus nly but in n case fr mre than 6 days and rats were put alng with male partners thereafter. EstiInatin f apprximate lethal dse (ALD).-Rats f either sex weighing ± 10 gms. were used in the experiment. Single increasing dses f rttlerin starting frm 62. mg./kg. were given in a sirigle rat and the general behaviur was bserved. An intermediate dse between ne which did nt kill and ne which killed was given t 3 rats and their weights recrded fr 3 days. Effect n islated uterus.-a pregnant guinea pig was killed by a blw n the head, the abdmen pened and the uterus remved. The uterine muscle was kept in Dale's slutin and ne piece was munted in an islated rgan bath maintained at 37-38 C and aerated artificially, Recrdings were taken n a drum. Fur such experiments were dne. TABLE I Shwing effect f rttlerin (2 mg./kg. per day given rally) n estrus behaviur frats bservedfr 1 days. N. f animals N. f cycles Mean length f cycle in days. SD ± t 10 Befre drug treatment 29.2 0.42.7 During drug treatment 14 12.0 3.87 P<O.OOI
170 ORAL CONTRACEPTIVE TABLE 2 Shwing effect frttlerin (2 mg./kg. per day) n fertility frats when given in varius stages f estrus cycle. estrus prestrus after mating diestrus N. f pairs N. f matings N. f sterile matings N. f fertile pairs N. fyung nes brn Sterile rats % Fertile rats % % fertility recrded within days after the cessatin f drug * 4 4 27 3 3 23 60 2 *One rat died the experiment. TABLE 3 Shwing e.fject f a single dse f rttlerin n weight and survival frats. Dse in mg./kg. N. f rats Time in hurs between drug administratin and death. Initial bdy weight in Gms. Bdy weight after 3 days in Gms. Lss in bdy weight in Gms. 62. 1 Nt dead 9.0 94.0 12 1 Nt dead 110.0 1080 2 20 1 Nt dead 103.0 101.0 2 37 1 Nt dead 102.0 99.0 3 00 1 Nt dead 96. 90.0 6. 62 3 Nt dead 101.3 96.0.3 70 1 4 hurs 93.0 0 1 2 hurs 97.0
VARMA, SAREEN, ROY AND GUJRAL 171 RESULTS AND DISCUSSION Table I shws that rttlerin prlngs the duratin f estrus cycle t a statistically significant degree. This is the result f prlngatin f the diestrus phase f the estrus cycle. There is an bvius disturbance in the nrmal estrgen-prgestrne-balance as regulated by pituitary gnadtrpins. The nature f the disturbance, hwever, is yet uncertain. Table 2 shws that s lng as the drug is administered estrus r after mating, it des nt affect the fertility f female rats. Hwever, when the drug is given prestrus, fertility is reduced t 60 per cent whereas administratin f the drug diestrus brings dwn the fertility t per cent. The drug therefre has t be given befre vulatin in rder t prevent fertility. It is fr this reasn that the drug treatment n the day f estrus and after mating has n effect n fertility. There is variable effect when the drug is given n the day f prestrus and cmplete infertility when administered diestrus. All the sterile rats the experiment mate successfully 20 t days after the cessatin f the drug. Nn-interference with the nrmal gestatin when treatment is started after mating strngly suggests that the drug is neither abrtifacient nr harmful t the develping fetus. This is further supprted by lack f effect n the islated uterine mvements f guinea pig as shwn in Figure I. Antifertility effect f the drug is nt permanent but certainly lasts fr smetime after the drug is stpped. Rttlerin 1. 2 mg. Pitcin 2. LV. Fig. I. Rttlerin 1.2 mg. Effect f rttlerin n islated gravid uterus. There is n effect n the spntaneus r pitcin - induced cntractins futerine muscle.
172 ORAL CONTRACEPTIVE A study ftable 3 shws that apprximate lethal dse (ALD) is 70 mg./kg. and animal dies 4 hurs after the drug feeding. There is a gradual lss f bdy weight fr 3 days after a single dse and the animals start gaining weight frm the furth day. This shws that the drug is absrbed slwly and is excreted slwly. This is cmpatible with the finding that the antifertility effect f the drug verruns the perid f drug treatment. SUMMARY 1. The antifertility effect f rttlerin seems t be due t a significant prlngatin f the duratin f estrus cycle mainly because f the lengthening f the perid f diestrus drug administratin. 2. The drug has t be given befre vulatin t prevent fertility. 3. The drug has n effect n the cntractin f islated gravid guinea pig uterus. 4. ALD f the drug in rats is quite high (70 mg./kg.) ACKNOWLEDGEMENT This study was financed by a grant frm the Indian Cuncil f Medical Research. 1. Allen, E. (1922): Am. J. Anat., 30, 297. REFERENCES 2. Gujral, M. L., Varma, D. R. and Sareen, K. N. (199 a): Ind. Jur. Med. Res., In Press. 3. Gujral, M. L., Varma, D. R., Sareen, K. N. and Ry, A. K. (199 b): Ind. Jur. Med. Res., In Press.