RESUMEN
BACKGROUND: Several malformations have been attributed to the process of vascular disruption. The central hypothesis for this etiology is that blood flow to a structure has been altered after that structure had formed normally. The decreased blood flow leads to hypoxia, endothelial cell damage, hemorrhage, tissue loss, and repair. After recovery, some structures are normal and others show either tissue loss or structural abnormalities, such as syndactyly and constriction rings. METHODS: The phenotypic features of the 7,020 infants with one or more malformations, who were born to women who had always planned to deliver at Brigham and Women's Hospital (BWH) between, 1972 and 2012, that is, maternal nontransfers, were reviewed. The phenotypes associated with vascular disruption, such as the amniotic band syndrome and terminal transverse limb defects (TTLD), were identified. RESULTS: One hundred and five fetuses and infants had malformations attributed to the process of vascular disruption. Some specific causes of the amniotic band limb deformity were identified. TTLD with associated small digit-like nubbins occurred at three levels: proximal forearm, wrist, and metacarpal-phalangeal joint. Other causes included severe hemoglobinopathies and exposures to misoprostol and to prenatal procedures. CONCLUSIONS: Malformations attributed to the process of vascular disruption were a distinctive entity, among the recognized etiologies. The timing of the causative event in the first trimester was established for infants with exposures to either the prostaglandin misoprostol or the prenatal diagnosis procedure chorionic villus sampling. One challenge is to identify the developmental steps in vascular disruption when no causative exposure can be identified.
Asunto(s)
Síndrome de Bandas Amnióticas/patología , Deformidades Congénitas de las Extremidades/patología , Flujo Sanguíneo Regional/fisiología , Malformaciones Vasculares/embriología , Malformaciones Vasculares/patología , Síndrome de Bandas Amnióticas/etiología , Hipoxia de la Célula/genética , Femenino , Hemoglobinopatías/etiología , Hemoglobinopatías/patología , Humanos , Hidranencefalia/etiología , Hidranencefalia/patología , Recién Nacido , Deformidades Congénitas de las Extremidades/etiología , Misoprostol/toxicidad , Síndrome de Poland/etiología , Síndrome de Poland/patología , Embarazo , Diagnóstico Prenatal , Malformaciones Vasculares/genéticaRESUMEN
OBJECTIVE: To report the prospective follow-up of pregnancies exposed to misoprostol during the first trimester and analyse the teratogenic risk depending on the indication for use. STUDY DESIGN: Prospective observational study of 265 women exposed to misoprostol during the first 12 weeks of pregnancy and followed until the delivery. Women were included if they or their physician had contacted a French pharmacovigilance centre before 22 weeks of gestation (WG) to obtain information on the risk of misoprostol exposure, and if there had been misoprostol exposure before 13 WG. Data were collected at the time of the first contact, and the pregnancy outcome was recorded at follow-up. Women were prospectively enrolled from January 1988 to December 2013. RESULTS: The main indication for misoprostol was voluntary abortion (60.9%). Ten major malformations (5.5%) (95% CI 2.65-9.82%) were reported and five of them were consistent with the pattern of malformations attributed to misoprostol: Möbius sequence, hydrocephalus, terminal transverse limb reduction associated with a clubfoot, syndactyly, and complete posterior encephalocele. The rate of malformations was higher, but not significantly, in women exposed to misoprostol for voluntary abortion (7.9%) compared with women exposed to misoprostol for other or unknown indications (3.2%). CONCLUSIONS: Our results confirmed a specific pattern of malformations due to misoprostol use in early pregnancy, even with low dose of misoprostol. Despite the small number of cases, we observed a higher proportion of major malformations in fetuses born to women who continued their pregnancy after a failed voluntary abortion with misoprostol. Further studies should be conducted to evaluate other potential factors, such as combination treatment with mifepristone and the socio-environmental characteristics in this group of women.
Asunto(s)
Anomalías Inducidas por Medicamentos/etiología , Abortivos no Esteroideos/toxicidad , Intercambio Materno-Fetal , Misoprostol/toxicidad , Teratógenos/toxicidad , Anomalías Inducidas por Medicamentos/epidemiología , Adulto , Antiulcerosos/efectos adversos , Femenino , Estudios de Seguimiento , Francia/epidemiología , Humanos , Hidrocefalia/inducido químicamente , Hidrocefalia/epidemiología , Recién Nacido , Misoprostol/efectos adversos , Síndrome de Mobius/inducido químicamente , Síndrome de Mobius/epidemiología , Farmacovigilancia , Embarazo , Primer Trimestre del Embarazo , Estudios Prospectivos , Riesgo , Adulto JovenRESUMEN
Misoprostol during the first trimester of pregnancy is associated with a specific malformative pattern (Moebius sequence and limb defects) whose incidence remains unknown. Data originate mostly from illegal use for abortion and are mainly retrospective. The present prospective controlled study analyses outcomes of first trimester misoprostol exposures after medical prescriptions. Malformation rate was higher among 236 pregnancies exposed before 12 gestational weeks (4%) than in 255 controls (1.8%), although not statistically significant (OR=2.2 [95% CI=0.6-7.7]). Three malformations (2%) in the exposed group were consistent with the misoprostol malformative pattern. This is the largest prospective study on first trimester misoprostol exposure and the first one relying on prescriptions. A trend toward a doubling of the overall rate of malformations was observed and for the first time an estimation of the incidence of misoprostol specific spectrum is proposed (2%). Brainstem injuries including severe trismus might be added to this specific pattern.
Asunto(s)
Anomalías Inducidas por Medicamentos/epidemiología , Abortivos no Esteroideos/toxicidad , Misoprostol/toxicidad , Efectos Tardíos de la Exposición Prenatal , Teratógenos/toxicidad , Adulto , Tronco Encefálico/anomalías , Tronco Encefálico/efectos de los fármacos , Prescripciones de Medicamentos , Femenino , Estudios de Seguimiento , Francia/epidemiología , Humanos , Incidencia , Deformidades Congénitas de las Extremidades/inducido químicamente , Deformidades Congénitas de las Extremidades/epidemiología , Síndrome de Mobius/inducido químicamente , Síndrome de Mobius/epidemiología , Pautas de la Práctica en Medicina , Embarazo , Resultado del Embarazo , Primer Trimestre del Embarazo , Estudios ProspectivosRESUMEN
Introducción. El misoprostol es una análogo de las prostaglandinas E1, actualmente autorizado en nuestro ámbito para el tratamiento de la ulcera de estómago y la prevención de lesiones gastrointestinales inducida por AINE. Pacientes y métodos. Mujer grávida 5 (3 partos eutócicos y 1 embarazo ectópico), con 32 semanas de gestación, acude a urgencias con desorientación, confusión, dolor abdominal intenso, T.a 41°C, 83/46 mmHg, 100 lpm. Se objetiva, taquicardia fetal con FCF basal 170 lpm con buena variabilidad y dinámica uterina irregular. La gestante refiere la autoadministración intravaginal de 4.000 μg misoprostol. Se inicia tratamiento sintomático con rehidratación, antitérmicos, antibióticos y maduración fetal. Tras 5 días de ingreso se produce parto eutócico con recién nacido vivo pretérmino. Conclusión. La sobredosis y la toxicidad del misoprostol en gestantes durante el tercer trimestre cursa con hipertermia, alteraciones de la consciencia, hipotensión, hipertonía uterina y/o polisistolia, llegando incluso a la muerte fetal. No existe antídoto, por lo tanto, el tratamiento es sintomático (AU)
Background. Misoprostol is a prostaglandin analogue, authorised use for the treatment of stomach or duedenal ulcers. In Spain, this drug is no authorised use for obstetrics and gynecology. Pacientes y métodos. Gravida 5, para 3, 1 ectopic, at 32 weeks's gestation. Presents disorientation, confusion, intense abdominal pain, hyperthermia 41 °C, 83/46 mmHg and 100 bpm. Fetal monitoring reveals foetal tachycardia of 170 bpm with good variability and irregular contractions. The woman admitted self-medication intravaginal 4.000 μg misoprostol. The treatment was: rehydration, antipyretic medication, fetal monitoring and treatment of suspected chorioamnionitis and prematurity. Five days after, normal delivery. Conclusion. Overdose and toxicity of misoprostol in pregnant women during the third trimester presents with hyperthermia, altered consciousness, hypotension, uterine hypertonia and or polisistolia, even fetal death. There is no antidote, so the treatment is symptomatic (AU)
Asunto(s)
Humanos , Femenino , Embarazo , Adulto , Misoprostol/toxicidad , Misoprostol/uso terapéutico , Tercer Trimestre del Embarazo , Complicaciones del Embarazo/epidemiología , UltrasonografíaRESUMEN
BACKGROUND: Approximately 15% of misoprostol-induced-abortions may not be successful, leading to in utero exposure to the drug and to the induction of a series of defects including central nervous system, limb and visceral defects. A common proposal is that the drug causes disruption of the fetal vasculature leading to embryonic or fetal hypoxia. AIM: To evaluate the teratogenicity of misoprostol using the rat post-implantation embryo culture. MATERIAL AND METHODS: Rat embryos were collected at the beginning of organogenesis and cultured in rat serum containing misoprostol at concentrations of 200, 2,000 or 20,000 pg/ml. Functionality, morphology and morphometry parameters were evaluated. RESULTS: Misoprostol induced a dose-dependent embryotoxic effect causing a decrease in embryo viability and function (poor vascular development and survival) and morphometry (alterations in branchial arches, heart and cephalic portions of the neural tube, among others). CONCLUSIONS: All the manifestations observed are indicative of the ability of misoprostol to directly induce developmental retardation and alterations.
Asunto(s)
Anomalías Inducidas por Medicamentos/embriología , Abortivos no Esteroideos/toxicidad , Embrión de Mamíferos/efectos de los fármacos , Misoprostol/toxicidad , Animales , Embrión de Mamíferos/anomalías , Femenino , Pruebas de Mutagenicidad/métodos , Embarazo , Ratas , Ratas Sprague-DawleyRESUMEN
We describe a boy who was exposed to misoprostol and methotrexate in the first trimester of gestation as a result of a failed medical abortion. He presented with severe growth retardation, skull defects, proptotic eyes, cleft palate, and severe micrognathia. There were bilateral defects of the upper and lower extremities, missing and hypoplastic ribs, and undescended testicles. He had clinical features of pulmonary hypoplasia with severe persistent pulmonary hypertension and remained ventilator-dependent until he expired. An autopsy revealed brain anomalies consistent with arrhinencephaly. Methotrexate is frequently used in conjunction with misoprostol to induce medical abortion, an off-label use as abortifacient. Both of these medications are well-established teratogens and have an X classification during pregnancy. Data from eight patients who were exposed to both medications in the first trimester indicate a significant teratogenic risk to the developing fetus. Reported anomalies include growth retardation, absence or hypoplasia of the frontal bones, craniosynostosis, large fontanelle, ocular hypertelorism, short palpebral fissures, wide nasal bridge, malformed and low-set ears, and micrognathia. Skeletal anomalies are frequent consisting of syndactyly, mesomelic shortening of the forearms, missing ribs, dislocated hips, and talipes equinovarus. The findings in our case are consistent with the pattern of abnormalities that have been reported in the literature. In addition, our patient had severe pulmonary hypoplasia and arrhinencephaly, anomalies that have not been described previously. This case adds to the documentation of the teratogenic effects of methotrexate and misoprostol on the developing fetus.
Asunto(s)
Anomalías Inducidas por Medicamentos/patología , Abortivos/toxicidad , Metotrexato/toxicidad , Misoprostol/toxicidad , Resultado Fatal , Humanos , Lactante , Recién Nacido , Masculino , Fenotipo , Teratógenos/toxicidadRESUMEN
Background: Approximately 15 percent of misoprostol-induced-abortions may not be successful, leading to in utero exposure to the drug and to the induction of a series of defects including central nervous system, limb and visceral defects. A commonproposal is that the drug causes disruption of the fetal vasculature leading to embryonic or fetal hypoxia. Aim: To evaluate the teratogenicity of misoprostol using the rat post-implantation embryo culture. Material and Methods: Rat embryos were collected at the beginning of organogenesis and cultured in rat serum containing misoprostol at concentrations of 200, 2,000 or 20,000 pg/ml. Functionality, morphology and morphometry parameters were evaluated. Results: Misoprostol induced a dose-dependent embryotoxic effect causing a decrease in embryo viability and function (poor vascular development and survival) and morphometry (alterations in branchial arches, heart and cephalic portions of the neural tube, among others). Conclusions: All the manifestations observed are indicative of the ability of misoprostol to directly induce developmental retardation and alterations.
Asunto(s)
Animales , Femenino , Embarazo , Ratas , Anomalías Inducidas por Medicamentos/embriología , Abortivos no Esteroideos/toxicidad , Embrión de Mamíferos/efectos de los fármacos , Misoprostol/toxicidad , Embrión de Mamíferos/anomalías , Pruebas de Mutagenicidad/métodos , Ratas Sprague-DawleyRESUMEN
OBJECTIVES: to ascertain the frequency and severity of complications resulting from artificial abortions and their possible association with the use of misoprostol. METHODS: a cross-sectional study was carried out. For ten months, a checklist (of World Health Organization criteria) was applied to all 543 women admitted to hospital for abortion at two hospitals in the city of Campinas, in the State of São Paulo, Brazil. Those classified as having a possibly, pro-bably or certainly artificial abortion were asked to fill in the questionnaire. RESULTS: of all the women admitted to hospital, 259 (48 percent) were classified as possibly, probably or certainly having an induced abortion and these filled in the questionnaire; 25 women stated that they had induced the abortion and, of these, nine mentioned the use of misoprostol. Infections and hemorrhaging were complications in 10 percent and 13 percent of the 259 women. Those who used misoprostol had fewer complications than those who used other methods, although this difference was not statistically significant, perhaps for reason of the low frequency for complications. CONCLUSIONS: the data show a reduction in the frequency and severity of complications arising from abortion, although it is not possible to point to the use of misoprosol as being responsible for this.
OBJETIVOS: verificar a frequência e a gravidade das complicações por abortos provocados e suas possíveis associações com o uso de misoprostol. MÉTODOS: estudo de corte transversal. Durante dez meses aplicou-se uma lista de verificação (critérios da World Health Organization) a todas as 543 mulheres internadas por aborto em dois hospitais na cidade de Campinas, São Paulo. Àquelas classificadas como aborto possível, provável ou certamente provocado foi aplicado também um questionário. RESULTADOS: dentre todas as mulheres internadas, 259 (48 por cento) foram classificadas como aborto possível, provável ou certamente induzido e responderam ao questionário; 25 mulheres declararam a indução do aborto e, destas, nove referiram uso de misoprostol. Complicações infecciosas e hemorrágicas ocorreram respectivamente em 10 por cento e 13 por cento das 259 mulheres. As que usaram misoprostol se complicaram menos que as que usaram outros métodos, porém essa diferença não foi estatisticamente significativa, talvez pela baixa freqüência de complicações. CONCLUSÕES: os dados mostram redução da freqüência e da gravidade das complicações do aborto, mas não permitem avaliar o papel do misoprostol.
Asunto(s)
Humanos , Femenino , Aborto Inducido , Misoprostol/administración & dosificación , Misoprostol/toxicidadRESUMEN
Moebius syndrome is a rare disease characterized by congenital facial paralysis and abducens palsy. Involvement of other cranial nerves, orofacial dysmorphism, and limb abnormalities are frequently associated. Reported here is the case of a 10-month-old child born with Moebius syndrome and presenting with holoprosencephaly, following exposure in utero to misoprostol. To our knowledge, this is the first published case report describing this association. The etiologic hypotheses of Moebius syndrome are also discussed.
Asunto(s)
Holoprosencefalia/inducido químicamente , Misoprostol/toxicidad , Síndrome de Mobius/inducido químicamente , Oxitócicos/toxicidad , Cuerpo Calloso/patología , Femenino , Cuarto Ventrículo/patología , Holoprosencefalia/complicaciones , Humanos , Lactante , Imagen por Resonancia Magnética/métodos , Síndrome de Mobius/complicacionesRESUMEN
In this study we have investigated the role of periaqueductal grey prostaglandin receptors in formalin-induced hyperalgesia in mice. Glutamate and GABA release changes have been monitored by in vivo microdialysis. Intra-periaqueductal grey microinjections of misoprostol, a non-selective prostaglandin receptor agonist, increased nociceptive responses in the formalin test only during the late phase. Prostanoid EP(1) (L-335677), EP(2) (AH 6809), EP(3) (L-826266) and EP(4) (L-161982) receptor antagonists prevented the nociceptive response induced by misoprostol in formalin-injected mice. Prostanoid EP(1), EP(2), EP(3) and EP(4) antagonists reduced, per se, the late hyperalgesic phase. Intra-periaqueductal grey perfusion with misoprostol increased periaqueductal grey glutamate, whereas it produced an increase followed by a decrease in GABA. Likewise, formalin increased glutamate and produced a biphasic response on GABA. When misoprostol was perfused in combination with the peripheral injection of formalin, we observed an increase of glutamate and an increase followed by a stronger decrease in GABA release. These data show that periaqueductal grey prostaglandin receptor stimulation increased formalin-induced nociceptive response in the late phase by increasing glutamate release and by producing a biphasic change in GABA release.
Asunto(s)
Hiperalgesia/fisiopatología , Sustancia Gris Periacueductal/efectos de los fármacos , Receptores de Prostaglandina E/fisiología , Acetatos/farmacología , Acrilamidas/farmacología , Animales , Compuestos de Bencilo/farmacología , Dimetilsulfóxido/administración & dosificación , Dimetilsulfóxido/toxicidad , Líquido Extracelular/efectos de los fármacos , Líquido Extracelular/metabolismo , Formaldehído , Ácido Glutámico/metabolismo , Hiperalgesia/inducido químicamente , Hiperalgesia/metabolismo , Inyecciones Intraventriculares , Masculino , Ratones , Microdiálisis , Misoprostol/administración & dosificación , Misoprostol/toxicidad , Naftalenos/farmacología , Dimensión del Dolor/métodos , Sustancia Gris Periacueductal/metabolismo , Sustancia Gris Periacueductal/fisiopatología , Antagonistas de Prostaglandina/farmacología , Receptores de Prostaglandina E/antagonistas & inhibidores , Tiofenos/farmacología , Triazoles/farmacología , Xantonas/farmacología , Ácido gamma-Aminobutírico/metabolismoRESUMEN
BACKGROUND: Prostaglandin has been reported to have protective effects against liver injury. Use of this agent in clinical settings, however, is limited because of drug-related side effects. This study investigated whether misoprostol, prostaglandin E1 analogue, and OP-41483, prostaglandin I2 analogue, which have fewer adverse effects with a longer half-life, attenuate ischemic liver damage. STUDY DESIGN: Thirty beagle dogs underwent 2 hours of hepatic vascular exclusion using venovenous bypass. Misoprostol was administered intravenously for 30 minutes before ischemia and for 3 hours after reperfusion. OP-41483 was administered intraportally for 30 minutes before ischemia (2 microg/kg/min) and for 3 hours after reperfusion (0.5 microg/kg/min). Animals were divided into five groups: untreated control group (n=10); high-dose misoprostol (total 100 microg/kg) group (MP-H, n=5); middle-dose misoprostol (50 microg/kg) group (MP-M, n=5); low-dose misoprostol (25 microg/kg) group (MP-L, n=5); and OP-41483 group (OP, n=5). Animal survival, hepatic tissue blood flow (HTBF), liver function, and histology were analyzed. RESULTS: Two-week animal survival rates were 30% in control, 60% in MP-H, 100% in MP-M, 80% in MP-L, and 100% in OP. The treatments with prostaglandin analogues improved HTBF, and attenuated liver enzyme release, adenine nucleotrides degradation, and histologic abnormalities. In contrast to the MP-H animals that exhibited unstable cardiovascular systems, the MP-M, MP-L, and OP animals experienced only transient hypotension. CONCLUSIONS: These results indicate that misoprostol and OP-41483 prevent ischemic liver damage, although careful dose adjustment of misoprostol is required to obtain the best protection with minimal side effects.
Asunto(s)
Epoprostenol/análogos & derivados , Isquemia/prevención & control , Hígado/irrigación sanguínea , Misoprostol/uso terapéutico , Inhibidores de Agregación Plaquetaria/uso terapéutico , Prostaglandinas Sintéticas/uso terapéutico , Análisis de Varianza , Animales , Perros , Relación Dosis-Respuesta a Droga , Epoprostenol/administración & dosificación , Epoprostenol/uso terapéutico , Epoprostenol/toxicidad , Femenino , Hígado/patología , Hígado/fisiopatología , Pruebas de Función Hepática , Misoprostol/administración & dosificación , Misoprostol/toxicidad , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/toxicidad , Prostaglandinas Sintéticas/administración & dosificación , Prostaglandinas Sintéticas/toxicidad , Daño por Reperfusión/prevención & controlAsunto(s)
Iloprost/farmacología , Misoprostol/farmacología , Protectores contra Radiación/farmacología , Animales , Radioisótopos de Cobalto , Diarrea/inducido químicamente , Esquema de Medicación , Sinergismo Farmacológico , Rayos gamma , Iloprost/toxicidad , Dosificación Letal Mediana , Masculino , Ratones , Ratones Endogámicos , Misoprostol/toxicidad , Protectores contra Radiación/toxicidad , Superóxido Dismutasa/efectos de los fármacos , Superóxido Dismutasa/metabolismo , Superóxido Dismutasa/efectos de la radiaciónRESUMEN
Misoprostol (MSP) is a synthetic prostaglandin E1 methyl analogue indicated for the prevention of gastric ulcers induced by nonsteroidal anti-inflammatory drugs (NSAIDs). Because of its abortifacient properties, MSP has been extensively misused for abortion induction in Brazil. Since abortion induction with MSP very often fails and pregnancy continues to term, there has been increasing concern regarding the potential teratogenicity of this PGE1 analogue in humans. The objective of the present study was to evaluate the embryotoxicity of MSP in mice. A single dose of MSP (20 or 30 mg/kg body weight) was administered to Han:NMRI mice (ca 60 days old) by gavage on day 10 of pregnancy. The number of treated mice was as follows: control, 19; MSP 20 mg/kg, 10; MSP 30 mg/kg, 28. Cesarean sections were performed on day 18 of pregnancy and the number of resorptions and implantation sites were recorded. Fetuses were weighed, examined for external malformations, fixed, cleared and stained with Alizarin Red S for skeleton evaluation. No evidence of embryotoxicity was found at the lower dose tested. A slight and reversible deficit in pregnancy weight gain (day 10-11: control, 1.3 +/- 0.3 g; MSP 20 mg/kg, -0.9 +/- 0.9 g; MSP 30 mg/kg, -1.7 +/- 0.6 g) was the only sign of maternal toxicity noted in both groups of mice treated with misoprostol.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Antiulcerosos/toxicidad , Desarrollo Embrionario y Fetal/efectos de los fármacos , Misoprostol/toxicidad , Anomalías Inducidas por Medicamentos , Animales , Antiulcerosos/administración & dosificación , Peso Corporal , Femenino , Humanos , Recién Nacido , Ratones , Ratones Endogámicos , Misoprostol/administración & dosificación , Embarazo , Aumento de Peso/efectos de los fármacosRESUMEN
Misoprostol (MSP) is a synthetic prostaglandin E1 methyl analogue indicated for the prevention of gastric ulcers induced by nonsteroidal anti-inflammatory drugs (NSAIDs). Because of its abortifacient properties, MSP has been extensively missused for abortion induction in Brazil. Since abortion induction with MSP very often fails and pregnancy continues to term, there has been increasing concern regarding the potential teratogenicity of this PGE1 analogue in humans. The objective of the present study was to evaluate the embryotoxicity of MSP in mice. A single dose of MSP(20 or 30 mg/kg body weight) was administered to Han:NMRI mice (ca 60 days old) by gavage on day 10 of pregnancy. The number of treated mice was as follows: control, 19; MSP 20 mg/kg, 10; MSP 30 mg/kg, 28. Cesarean sections were performed on day 18 of pregnancy and the number of resorptions and implantation sites were recorded. Fetuses were weighed, examined for external malformations, fixed, cleared and stained with Alizarin Red S for skeleton evaluation. No evidence of embryotoxicity was found at the lower dose tested. A slight and reversible deficit in pregnancy weight gain ...
Asunto(s)
Animales , Femenino , Ratones , Desarrollo Fetal/efectos de los fármacos , Misoprostol/toxicidad , Anomalías Inducidas por Medicamentos , Peso Corporal , Ratones Endogámicos , Misoprostol/administración & dosificación , Aumento de Peso/efectos de los fármacosRESUMEN
SC-53450 is a new polybutadiene-based polymer system with an acid labile diisopropyl silyl ether linker to which the active isomer of misoprostol (SC-30249) is attached covalently at position C-11. It was studied in rats and dogs to define its profile of gastrointestinal effects relative to misoprostol-hydroxypropyl methylcellulose (HPMC) and the systemic availability of prostaglandin from the polymer. Results of rat studies indicate that SC-53450 has a spectrum of mucosal protective activity similar to misoprostol-HPMC, being protective against indomethacin-induced gastric, cysteamine/indomethacin-induced duodenal and indomethacin-induced lower small bowel damage. SC-53450, in contrast to misoprostol-HPMC, was not diarrheagenic in the rat when administered intragastrically. The observation that SC-53450 is more than 4 times more potent than misoprostol-HPMC suggests the possibility of sustained gastric availability of the prostaglandin SC-30249. SC-53450 exhibited gastric antisecretory activity in histamine-stimulated gastric fistula dogs and protected against acidified aspirin-induced gastric damage in normal fasted beagles. Rat and dog experiments indicate that little, if any, polymer-derived prostaglandin is available systemically, suggesting SC-53450 will have reduced abuse potential in abortion induction. SC-53450 is a potential candidate to replace the present misoprostol formulation in the marketplace for the prevention of nonsteroidal anti-inflammatory drug-induced gastric damage.