Teratogenicity In Rats Research Articles

Acute, chronic, and genotoxic studies on the protopine total alkaloids of the Macleaya cordata (willd.) R. Br. in rodents.

The protopine alkaloids are widely distributed within the opium poppy family and have a wide range of pharmacological effects. MPTA is a product of the protopine total alkaloids extracted from the Macleaya cordata (Willd.) R. Br. Previously, we reported good anti-inflammatory activity of MPTA as well as oral acute and sub-chronic toxicity studies in rats. In order to perform a systematic toxicological safety assessment of MPTA, oral acute toxicity, genotoxicity (bone marrow cell chromosome aberration test, sperm abnormality test, bone marrow cell micronucleus test, and rat teratogenicity test), and chronic toxicity in mice were performed in this study. In the oral acute toxicity test, the LD50 in ICR mice was 481.99 mg/kg, with 95% confidence limits ranging from 404.27 to 574.70 mg/kg. All three mutagenicity tests tested negative in the range of 60.25–241.00 mg/kg. The results of the teratogenicity test in rats showed no reproductive or embryonic developmental toxicity at only 7.53 mg/kg, which can be considered as a no observed effect level (NOEL) for the teratogenicity test. Therefore, MPTA is safe for use at the doses tested, but attention should be paid to the potential risk to pregnant animals and the safety evaluation and toxicity mechanisms in target animals should be further investigated.

Preclinical safety evaluation of Macleaya Cordata extract: A re-assessment of general toxicity and genotoxicity properties in rodents.

Macleaya cordata extract (MCE) is widely used for its diverse pharmacological actions and beneficial effects on farm animals. Modern pharmacological studies have shown that it has anti-inflammatory, anti-cancer, and anti-bacterial activities, and is gradually becoming a long-term additive veterinary drug used to improve animal intestinal health and growth performance. Although some evidence points to the DNA mutagenic potential of sanguinarine (SAN), a major component of MCE, there is a lack of sufficient basic toxicological information on the oral route, posing a potential safety risk for human consumption of food of animal origin. In this study, we assessed the acute oral toxicity, repeated 90-day oral toxicity and 180-day chronic toxicity of MCE in rats and mice and re-evaluated the genotoxicity of MCE using a standard combined in vivo and ex vivo assay. In the oral acute toxicity test, the LD50 for MCE in rats and mice was 1,564.55 mg/kg (95% confidence interval 1,386.97–1,764.95 mg/kg) and 1,024.33 mg/kg (95% confidence interval 964.27–1,087.30 mg/kg), respectively. The dose range tested had no significant effect on hematology, clinical chemistry, and histopathological findings in rodents in the long-term toxicity assessment. The results of the bacterial reverse mutation, sperm abnormality and micronucleus test showed negative results and lack of mutagenicity and teratogenicity; the results of the rat teratogenicity test showed no significant reproductive or embryotoxicity. The results indicate that MCE was safe in the dose range tested in this preclinical safety assessment. This study provides data to support the further development of maximum residue limits (MRLs) for MCE.

Prenatal developmental toxicity study of herbal tea of Moringa stenopetala and Mentha spicata leaves formulation in Wistar rats

BackgroundMoringa stenopetala and Mentha spicata have long been used to treat diabetes, hypertension, asthma, and other ailments. Herbal tea of M. stenopetala and Mentha spicata leaves formulation showed better antidiabetic and antihypertensive activities. This study investigated the prenatal developmental toxicity potential of the herbal tea of M. stenopetala and M. spicata leaves blend in rats. MethodsWistar pregnant rats were randomly distributed into four groups (n = 8). Group I (control) dams received distilled water. Group II-IV dams were treated with 559.36, 1118.72, and 2237.44 mg/kg of herbal tea of M. stenopetala and Mentha spicata leaves formulations, respectively, during days 5–19 of gestation. Maternal mortality, clinical signs, body weight changes, and food consumption were recorded. On gestation day 20, cesarean sections were performed, and maternal parameters of systemic toxicity (e.g., body weight, serum biochemistry, organ weight, and macro-pathology) as well as reproductive toxicity (e.g., number of corpora lutea, implantations, resorptions (early/late), pre/postimplantation losses, number of fetuses (live/dead), and fetal body weights, length, and their sex ratio) were evaluated. Fetuses were further examined for external, soft tissue, and skeletal alterations. ResultsNo herbal tea-related maternal deaths or overt toxic symptoms were observed. The measured maternal systemic and reproductive toxicity parameters showed no herbal tea-associated significant alterations at any dosage levels. Moreover, there were no overt toxic effects of the herbal tea on the fetal external, visceral, or skeletal prenatal growth and development. ConclusionThe study findings demonstrated that the herbal tea of M. stenopetala and M. spicata leaves blend could be relatively safe/low toxic to pregnant rats and developing fetuses. The no-observed-adverse-effect level (NOAEL) of herbal tea for maternal toxicity, fetotoxicity, and teratogenicity in rats is estimated to be > 2237.44 mg/kg/day.

Some Teratogenic Outcomes in Rats Exposed to Zinc Chloride Pre and Post Pregnancy

The aim of present study was to evaluate the possibility of teratogenicity in rats when exposed to zinc chloride (ZnCl2) pre and post pregnancy. To achieve this goal, a total of 40 mature Albino Wistar female rats were divided equally into four groups as follows: T1, dosed 0.7 mg/day ZnCl2 for two months before mating and till to the day 5th of pregnancy, the females of this group were mated with males dosed 0.7 mg/day ZnCl2 for two weeks before mating; T2, dosed 0.7 mg/day ZnCl2 for two months before mating and till to the day 16th of pregnancy and then were mated with control males (not exposed to any level of ZnCl2); T3, dosed 0.7mg/day ZnCl2 for two months before mating and till the end of pregnancy and were mated with control males; Control, dosed with water free from ZnCl2 along the period of experiment and were mated with control males. At the end of each pregnancy phase, results revealed that alpha fetoprotein serum levels were significantly (P<0.05) higher in all treatment groups compared to the control group, and the most prominent increase was observed in the T3 group. All treatment groups showed a significant (P<0.05) decrease in gestation, viability, and lactation indices when compared to the control group, with the T3 group showing the most significant decrease. Additionally, on days 1, 4, 7, 14, and 21 of lactation period, there was a significant (P<0.05) decrease in mean pup body weights in treated groups compared to the control group, with T3 group having the most prominent body weight decrease. The findings of this study revealed that ZnCl2 at a daily dose of 0.7 mg may cause teratogenic defects in rats at various stages of pregnancy, particularly at the third stage. As high-risk groups, pregnant women and children should use Zn supplementation carefully, whether as a food additive or for self-medication. Simultaneously, evaluating effect of low-dose Zn supplementation over a longer duration is required.

Palmitoylethanolamide: Prenatal Developmental Toxicity Study in Rats.

Palmitoylethanolamide (PEA) is an endogenous ethanolamine playing a protective and homeodynamic role in animals and plants. Prenatal developmental toxicity of PEA was tested following oral administration to pregnant female Wistar rats, from days 0 to 19 of gestation, at dosage of 250, 500, or 1,000 mg/kg body weight, according to Organisation for Economic Co-operation and Development Test Guideline No. 414. On gestation day 20, cesarean sections were performed on the dams, followed by examination of their ovaries and uterine contents. The fetuses were further examined for external, visceral, and skeletal abnormalities. Palmitoylethanolamide did not cause any alterations at any of the given dosages in the measured maternal parameters of systemic toxicity (body weight, food consumption, survival, thyroid functions, organ weight, histopathology), reproductive toxicity (preimplantation and postimplantation losses, uterus weight, number of live/dead implants and early/late resorptions, litter size and weights, number of fetuses, their sex ratio), and fetal external, visceral, or skeletal observations. Any alterations that were recorded were “normal variations” or “minor anomalies,” which were unrelated to treatment with PEA. Under the condition of this prenatal study, the no-observed-adverse-effect level of PEA for maternal toxicity, embryotoxicity, fetotoxicity, and teratogenicity in rats was found to be >1,000 mg/kg body weight/d. It indicates that PEA is well tolerated by and is safe to pregnant rats even at a high dose of 1,000 mg/kg body weight/d, equivalent to a human dose of greater than 9.7 g/d. This prenatal developmental toxicity study contributes greatly in building a robust safety profile for PEA.

Molecular mechanisms of Cisplatin- induced placental toxicity and teratogenicity in rats and the ameliorating role of N-acetyl-cysteine

The aim of the present study is to investigate the molecular mechanisms of Cisplatin- induced placental toxicity and teratogenicity in rats and the ameliorating role of N-acetyl-cysteine (NAC). Cisplatin was administrated intraperitoneally at 5 mg/kg.b.wt as a single dose on the 12th day of gestation while NAC was administered orally throughout gestation either alone or in concomitant injection of Cisplatin at 200 mg/kg.b.wt. Cisplatin + NAC group showed reduction in the elevated morphological, visceral and skeletal abnormalities as well as the morphological and histopathological changes in placenta compared to Cisplatin - treated rats. Importantly, NAC attenuated Cisplatin-induced placental apoptosis through down-regulation of Fas and Caspase-3 genes expression. In conclusion, induction of placental apoptosis by overexpression of Fas and Caspase-3 genes gives a new insight into the mechanism of Cisplatin teratogenicity. The protective role of NAC, on the other hand, was characterized by attenuation of Fas and Caspase-3 genes- mediated apoptosis.

Patulin Induced Dominant Lethal Gene in Mature Male and/or Female Rats

Many fungi including Penicillium and Aspergillus species produces patulin in the contaminated foods. Patulin is a heterocyclic unsaturated lactone that reacts with SH group of biological molecules causing harmful effects in human and animal tissues. Hence, the present investigation was designed to evaluate the possible teratogenic effect of patulin (0.002mg/kg b. wt) which was examined through the induction of dominant lethal gene and the alteration in number of live births in the female rats . Results and Conclusion: patulin is a dangerous teratogen in rats. This was confirmed by the significant increase in the percentage of maternal and embryo toxicities.

Ondansetron and teratogenicity in rats: Evidence for a mechanism mediated via embryonic hERG blockade

The potent hERG channel blocking drug ondansetron is used off-label for treatment of nausea and vomiting in early pregnancy. Some human epidemiological studies have associated ondansetron with fetal cardiovascular defects and orofacial clefts. This study investigated the effects of ondanestron on embryonic heart rhythm of gestational day (GD) 13 rat embryos in vitro and then integrated the results with published animal teratology, and animal and human pharmacokinetic studies to perform a risk evaluation. Ondansetron caused concentration dependent bradycardia and arrhythmia. Cardiovascular malformations in rats occurred at exposures slightly higher than those in early human pregnancy. Together the results suggest that ondansetron can have teratogenic potential in rats and humans mediated via hERG block and severe heart rhythm disturbances in the embryo. The risk may be increased in human pregnancy if additional risk factors are present such as hypokalemia.

The Reproductive Toxicity of Mequindox in a Two-Generation Study in Wistar Rats.

Mequindox (MEQ), belonging to quinoxaline-di-N-oxides (QdNOs), has been extensively used as a synthetic antibacterial agent. To evaluate the reproductive toxicity of MEQ, different concentrations of MEQ were administered to Wistar rats by feeding diets containing 0, 25, 55, 110, and 275 mg/kg, respectively. Each group consisting of 25 males and 25 females (F0) was treated with different concentrations of MEQ for 12-week period time, prior to mating and during mating, gestation, parturition and lactation. At weaning, 25 males and 25 females of F1 generation weanlings per group were randomly selected as parents for the F2 generation. Selected F1 weanlings were exposed to the same diet and treatment as their parents. The number of live litter and indexes of mating and fertility were significantly decreased in the F1 and F2 generation at 110 and 275 mg/kg groups. Significant decrease in pup vitality during lactation was observed in F1 litter at 275 mg/kg group, in F2 litter at 55, 110, and 275 mg/kg groups. A downward trend in the body weights was observed in F1 pups at 55, 110, and 275 mg/kg MEQ groups, and in F2 pups at 110 and 275 mg/kg MEQ groups. The changed levels of ALT, AST, CREA, BUN, UA, Na, and K were noted in the serum of rats. The histopathologic examination showed that MEQ induced toxicity in the liver, kidney, adrenal, uterus and testis. The no-observed-adverse-effect level (NOAEL) for reproduction toxicity of MEQ was 25 mg/kg diet. The malformations and severe maternal toxicity of MEQ caused adverse effects on the conceptus and embryo, which result in fetal malformations and fetal deaths. In summary, the present study showed that MEQ induced maternal, embryo and reproductive toxicities as well as teratogenicity in rats.

Usefulness of zebrafish in evaluating drug-induced teratogenicity in cardiovascular system

To confirm the usefulness of zebrafish for evaluating the teratogenic potential of drug candidates, the effect of O-ethylhydroxylamine hydrochloride (OHY), which induces mutagenesis by methylation, was evaluated in teratogenicity studies in rats and zebrafish. In the rat teratogenicity study, OHY-induced cardiovascular malformations such as increased abnormal vascular structures and ventricular septal defects. In the teratogenicity study using zebrafish-injected microspheres and green fluorescent protein-expressing Tg zebrafish (flk1:EGFP), OHY exposure was associated with the loss or malformation of the mandibular arch, opercular artery, and fourth branchial arch. These results suggested that OHY-induced external malformations in zebrafish eleutheroembryos adequately reflect OHY’s teratogenicity in rat fetuses. Moreover, the zebrafish teratogenicity study incorporating vascular morphological examinations, including those of blood vessels in the heart, head and trunk, is an easy and reliable screening method to detect potential drug-induced teratogenicity and phenotypic characteristics.

Comparative study of the effect of taurine, caffeine, and /or paracetamol on male fertility and teratogenicity in rats

Caffeine (CF) is one of the popular nutrients that have been implicated as a risk factor for infertility. Taurine (TAU) is the most abundant free amino-acid present in mammalian tissues and cells. Paracetamol (PCM) is an effective oral analgesic. The present study represented to evaluate the effects of CF, TAU and /or PCM on male fertility in rat and the development of their fetuses. The 1st group was kept as a normal control received distilled water. The 2nd, 3rd and 4th groups received orally 250 mg / kg, 40 mg / kg and 270 mg/ kg of TAU, CF and PCM, respectively. In addition, the 5th, 6th, 7th, and 8th groups received TAU+CF, TAU+PCM, CF+PCM and TAU+CF+PCM, respectively, for 45th consecutive days. Then blood samples were taken to determine the testosterone and FSH level, and total pro-oxidant. Moreover, in testes, malondialdehyde and nitrite/nitrate were estimated. Besides, the abnormality of sperms, sperm counts and percentage of sperm motilities were evaluated. These males were allowing to mated with untreated female rats to determined the rate of pregnancy and study any malformation in their fetuses. The results revealed that each of CF and/ or PCM decreased the weights of fetuses, as well as sperm counts and motilities significantly. Besides, percentages of head and tail abnormalities were increased in CF and/or PCM. The histopathological examination revealed presence of marked degenerative changes in testes in CF and/or PCM-treated groups. In conclusion, we observed that TAU almost improved undesirable effects induced by PCM or/and CF.

Investigation on Toxicity and Teratogenicity in Rats of a Retinoid-Polyamine Conjugate with Potent Anti-Inflammatory Properties.

Previous studies have shown that N(1),N(12)-bis(all-trans-retinoyl)spermine (RASP), a retinoid analog, inhibits RNase P activity and angiogenesis in the chicken embryo chorioallantoic membrane, demonstrates anti-tumor activity on prostate cancer cells, and acts as anti-inflammatory agent, being more effective and less toxic than all-trans retinoic acid. In an attempt to further characterize the biological profile of RASP, we tested its effects on organ toxicity and teratogenicity by daily oral gavage of RASP at a level of 50 mg/Kg of body weight in two generations of rats. We found that this compound does not induce changes to the body growth, the appearance of physical features, and the animal's reflexes. Additionally, no substantial histopathological lesions were found in brain, heart, lung, thymus, liver, thyroid gland, adrenal gland, pituitary gland, kidneys, spleen, skin, femora, prostate, testis, epididymis, vagina, uterus, and ovaries of RASP-treated animals. These results suggest RASP, as a promising lead compound for the treatment of several dermatological disorders and certain cancer types, has apparently minimal toxic side-effects as revealed in this two-generation reproduction study in rats.

Zeaxanthin: Review of Toxicological Data and Acceptable Daily Intake

Zeaxanthin is a nutritional carotenoid with a considerable amount of safety data based on regulatory studies, which form the basis of its safety evaluation. Subchronic OECD guideline studies with mice and rats receiving beadlet formulations of high purity synthetic zeaxanthin in the diet at dosages up to 1000 mg/kg body weight (bw)/day, and in dogs at over 400 mg/kg bw/day, produced no adverse effects or histopathological changes. In developmental toxicity studies, there was no evidence of fetal toxicity or teratogenicity in rats or rabbits at dosages up to 1000 or 400 mg/kg bw/day, respectively. Formulated zeaxanthin was not mutagenic or clastogenic in a series of in vitro and in vivo tests for genotoxicity. A 52-week chronic oral study in Cynomolgus monkeys at doses of 0.2 and 20 mg/kg bw/day, mainly designed to assess accumulation and effects in primate eyes, showed no adverse effects. In a rat two-generation study, the NOAEL was 150 mg/kg bw/day. In 2012, this dosage was used by EFSA (NDA Panel), in association with a 200-fold safety factor, to propose an Acceptable Daily Intake equivalent to 53 mg/day for a 70 kg adult. The requested use level of 2 mg/day was ratified by the EU Commission.

Quercetin preventive effects on theophylline-induced anomalies in rat embryo.

Theophylline has been shown to cause heart anomaly in animal and human fetus. The present study aimed to investigate the protective effect of quercetin on theophylline-induced heart disorders in rat embryo. Theophylline-induced teratogenicity in rats was used as the animal model. Pregnant rats were administered theophylline (259 mg/kg, po) or theophylline plus quercetin (259 mg/kg, po and 100 mg/kg, ip, respectively) on 9th and 10th days of pregnancy. On day 19, cardiac changes were assessed, measuring malondialdehyde (MDA) and glutathione peroxidase (GPx) activity levels in blood samples and also the fetus heart weight. Histopathological examination was also performed on all specimens. Theophylline-treated rats showed MDA level elevation and GPx activity reduction. Quercetin treatment improved heart conditions and resulted in a significant reduction in MDA levels and elevation in GPx activity. Moreover, co-administration of quercetin and theophylline increased the heart weight significantly. Furthermore, histophatological study showed no changes in the treated groups. This study demonstrated that quercetin have beneficial effects on theophylline-induced-anomalies in rat embryo.

A study of the effect of (2"R)-4'-O-tetrahydropyranyladriamycin, a new antitumor antibiotic, on reproduction. II. Its teratogenicity in rats and rabbits

This paper describes the embryotoxicity and teratogenic effects of (2"R)-4'-O-Tetrahydropyranyladriamycin (THP). The drug was administered intravenously to female rats at 0.01, 0.03, 0.1 or 0.3 mg/kg daily from day 7 to day 17 of pregnancy and to female rabbits at 0.01, 0.05 or 0.1 mg/kg daily from day 6 to day 18 of pregnancy. Results were summarized as follows. Rats THP, at the highest dose of 0.3 mg/kg, decreased body weight gains of pregnant females. This dose caused a decrease in body weights of fetuses, tendencies to increase the rate of death of fetuses or of resorption, an increase in the number of lumbar vertebrae and a delayed ossification of forelimbs of fetuses. Other parameters were not affected by THP at any dose levels. At any dose levels, THP did not produce external, visceral or skeletal malformations in the offspring (F1), nor did it affect the development, physiological functions, behavior, mating, fertility or pregnancy of the offspring. However, at the highest dose level, THP decreased the weight of testes of the offspring. The results suggest that the maximum "no effect" dose level of THP to pregnant females and offspring is 0.1 mg/kg/day intravenously. Rabbits The highest dose of THP, 0.1 mg/kg, decreased the consumption of food and water by pregnant females, but at any dose levels, it did not affect their body weight gain. THP did not cause teratological effects such as external malformation or visceral and skeletal anomalies in the fetuses at any dose levels tested. The results suggest that the maximum "no effect" dose of THP is 0.05 mg/kg/day intravenously to pregnant females and above 0.1 mg/kg/day intravenously to fetuses.

Qualitative identification of the active principles in Citrullus colocynthis and evaluation of its teratogenic effects in albino rats

Background: This study was designed to identify the active contents of Citrullus colocynthis plant and to examine their teratogenicity in rats. The fruit pulp of the poisonous plant was collected randomly from Suq-Alkhamis district, Tripoli, Libya. Methods: The glucoside colocynthin was isolated by lead acetate method while the alkaloids and saponins were isolated by maceration method. These active principles were then identified by chemical tests, color reactions and thin layer chromatography. Possible teratogenic effects of the fruit pulp extract was investigated by its administration to twelve pregnant rats on the 7 th day of gestation at a dose of 40.6 mg/kg body weight that is equivalent to one fourth of the LD 50 of the extract. Results: Gross anatomical observation on the 20 th day of gestation revealed a high percentage of resorbed fetuses, smaller size and weight fetuses as well as absence of coccygeal vertebrae, metacarpal and metatarsal bones, and carpal and tarsal bones. Conclusions: It could be concluded that the extract of fruit pulp of Citrullus colocynthis, obtained from Libya, contain glucosidal as well as other principles that may cause teratogenic effects if given during at the early stage of pregnancy.

Using Activated Carbon Nanoparticles to Decrease the Genotoxicity and Teratogenicity of Anticancer Therapeutic Agents

One of the key obstacles against the success in cancer chemotherapy is the toxic and side effects of the chemotherapeutic agents. The avoidance of these toxic and side effects will greatly improve the therapeutic effects of anticancer drugs while decrease the pains of the patients. Here we show that activated carbon nanoparticles (ACNP), one of the mesoporous nanoparticles, can decrease the genotoxicity and teratogenicity of mitomycin C (MMC). To study the effects of ACNP on genotoxicity and teratogenicity of MMC, methods of PCE micronucleus test, Chinese hamster lung cell chromosome aberration experiment and rat teratogenicity were employed to observe the differences in genotoxicity and teratogenicity between ACNP-adsorbed MMC (ACNP-MMC) and free MMC. Results demonstrated that free MMC 0.16-5.0 microg/kg significantly increased the positive rate of PCE micronucleus test, the chromosome aberration rate and rat teratogenecity, but ACNP-MMC did not increased these heredity and reproduction toxicological indexes in a dose range of 0.625-10.0 microg/kg. From these results, it can be concluded that ACNP-MMC have significant effects to decrease the genotoxicity and teratogenicity effects of MMC. These results will have a considerable impact on the strategy of anticancer chemotherapy.

Effects of gestational exposure to 1.95‐GHz W‐CDMA signals for IMT‐2000 cellular phones: Lack of embryotoxicity and teratogenicity in rats

The present study was designed to evaluate whether gestational exposure to an EMF targeting the head region, similar to that from cellular phones, might affect embryogenesis in rats. A 1.95-GHz wide-band code division multiple access (W-CDMA) signal, which is one applied for the International Mobile Telecommunication 2000 (IMT-2000) system and used for the freedom of mobile multimedia access (FOMA), was employed for exposure to the heads of four groups of pregnant CD(SD) IGS rats (20 per group) for gestational days 7-17. The exposure was performed for 90 min/day in the morning. The spatial average specific absorption rate (SAR) for individual brains was designed to be 0.67 and 2.0 W/kg with peak brain SARs of 3.1 and 7.0 W/kg for low (group 3) and high (group 4) exposures, respectively, and a whole-body average SAR less than 0.4 W/kg so as not to cause thermal effects due to temperature elevation. Control and sham exposure groups were also included. At gestational day 20, all dams were killed and fetuses were taken out by cesarean section. There were no differences in maternal body weight gain. No adverse effects of EMF exposure were observed on any reproductive and embryotoxic parameters such as number of live (243-271 fetuses), dead or resorbed embryos, placental weights, sex ratios, weights or external, visceral or skeletal abnormalities of live fetuses.

Diphenyl ditelluride effect on embryo/fetal development in mice: Interspecies differences

It is well established that diphenyl ditelluride, (PhTe) 2, is a potent teratogen in rats, however, little is known about its effects on embryo/fetal development in mice. The present study was undertaken to investigate whether any differences exist on embryo/fetal development of mice exposed to (PhTe) 2 during distinctive periods of gestation compared to rats. Dams were treated subcutaneously (s.c.) with 0.12 or 60.0 mg/kg (PhTe) 2 on gestational day (GD) 4, 8 or 14. Cesarean section was performed on GD18 and external and skeletal alterations were examined. The lower dose did not affect any parameter evaluated in mouse fetuses. The maternal body weight for 60 mg/kg (PhTe) 2 groups, at all periods studied, was not affected. Maternal liver and spleen weights were increased at GD8. At GD14, maternal relative weight of kidney was also increased. A significant reduction in the number of implantation sites at GD4 was found. At GD4 and GD14, there was a reduction in the fetal weight and biometry. A few signs of reduced ossification in sternebrae and limbs were observed at GD14 in (PhTe) 2 group. In conclusion, (PhTe) 2 was not toxic to dams and affected some fetal endpoints only at the dose about 500-fold higher than the dose that was teratogenic in rats, suggesting a different developmental toxicity induced by (PhTe) 2 among species. Thus, the mice were less susceptible to toxic effects induced by (PhTe) 2 than were rats.

Critical period and minimum single oral dose of ochratoxin A for inducing developmental toxicity in pregnant Wistar rats

Ochratoxin A (OTA), a potent in vivo teratogen, has been tested in various laboratory animal species. Present investigation was conducted to determine critical dose and critical time for the developmental toxicity of OTA in pregnant Wistar rats after single oral dose administration. OTA at different graded dose levels (2–4 mg/kg body weight) and at different gestation days (6–15), caused variable developmental defects in developing fetuses. OTA at 2.75 mg/kg body weight, dissolved in 0.1 M sodium bicarbonate (vehicle) and administered by oral intubation as a single dose on one of the gestational days 6–15, caused significant maternal toxicity in the dams and various gross, visceral and skeletal anomalies in the fetuses. The major gross malformations were external hydrocephaly, incomplete closure of skull and omphalocele. Internal hydrocephaly, microphthalmia, enlarged renal pelvis and renal hypoplasia were the main internal soft tissue anomalies. Major skeletal defects were developmental defects in skull bones, sternebrae, vertebrae and ribs. The gestational days 6 and 7 were found to be the most critical for the induction of teratogenicity in rats. Single oral dose of 2.75 mg/kg body weight OTA was found to be the minimum effective teratogenic dose in pregnant Wistar rats.