[Report of the 4th International Conference on Envenomations by Snakebites and Scorpion Stings in Africa, Dakar, April 25-29, 2011]. / 4(e) Conférence internationale sur les envenimations par morsures de serpent et piqûres de scorpion en Afrique : Dakar, 25-29 avril 2011.

The authors present a summary of the proceedings and the recommendations of the Fourth International Conference on Envenomations by Snakebites and Scorpion Stings in Africa, held from 25 to 29 April 2011 in Dakar. After a two-day workshop for Senegalese health personnel on the most relevant aspects of the management of envenomations, about 270 participants met to share their experiences in the field. Nearly a hundred oral and poster presentations were made on the epidemiology of snakebites and scorpion stings in Africa, the composition and action of venoms and the manufacture and use of antivenoms. The last day was devoted to an institutional debate involving experts, representatives of national health authorities and concerned professionals (physicians, pharmacists, nurses and traditional healers) as well as members of the pharmaceutical industry to discuss and elaborate a set of recommendations. It was agreed that it is necessary to improve knowledge of the epidemiological situation by case reporting. Quality control of antivenoms and procedures for their registration at the level of national health authorities should aim at improving the distribution of safe and effective antivenoms in peripheral health centers for the better assessment of victims. It was also recommended that adequate training should be provided for health personnel in all aspects of medical management of envenomations. Equitable distribution of funding and the establishment of a network of African experts were also discussed in the conference.

[Study of two cases of virological failure antiretrovirals in the Institute of Social Hygiene (ISH) of Dakar]. / Etude de deux cas d'echec virologique aux antiretroviraux a L'Institut D'Hygiene Sociale (IHS) de Dakar.

CONTEXT: The long term treatment of VIH/SIDA puts down majors risks among which the happening of virological failure or resistance to the anti-retroviral treatment at the patient. OBJECTIVE: To study the cases of resistance to antiretroviral to a cohort of 70 patients of the social hygiene of Dakar. METHOD: This is a retrospective study of the medical records of 70 patients followed in the social hygiene of Dakar during 24 mouths. Data were gathered with the help of form having following variables: The period of meadow inclusion; The period of inclusion; The period of rebound virological; The rate of CD4 count; The viral load and weight of patients. RESULTS: Average of age in inclusion is of 47.5 years with a sex ratio of the women HIV 1 was dominant. Two cases of virological failure were found or (2.8%). The patient 1 was the stade II of the classification of the with as therapeutic class 2INTI + 2 INNTI. It was in stage asymptomatic with as therapeutic protocol DDI + 3TC + NVP. The patient 2 was at the stade III of the whom that is to say at the stade in AIDS with as therapeutic class: 2INTI + 1IP with the protocol of treatment DDI + 3TC +IND. CONCLUSION: The virological failure to the newly infected persons noticed more and more in the world poses a problem of public health because it constitutes a threat for the success of the programs of treatment of the HIV/AIDS.

Developpement d'une matrice ethylcellulose/eudragitr pour la liberation controlee et continue de l'insuline

But : Le diabete de type I est une maladie chronique necessitant des prises repetees d'insuline toute une vie durant par voie parenterale. Ce mode d'administration en plus d'etre traumatisant peut poser un probleme d'observance du traitement chez le patient. Dans le souci de pallier ces difficultes; nous avons envisage le developpement d'une matrice ethylcellulose/eudragitr susceptible de faciliter la mise au point d'un systeme therapeutique transdermique de liberation controlee (STTLC) de l'insuline. Materiel et methode : Comme principe actif nous avons utilise de l'insuline humaine anhydre Actrapidr HM des laboratoires Novo Nordisk; les excipients sont l'ethylcellulose; les Eudragitr RS 100 et le butylphtalate. Nous avons elabore deux matrices Ethylcellulose/Eudragit dans les rapports 1 : 1 et 2 : 1 dans lesquels sont incorporees differentes proportions d'insuline. Resultats : L'etude de la liberation de l'insuline en milieu tampon phosphate a pH 7;4 a montre une liberation continue avec des profils fortement dependants du rapport Ethylcellulose/Eudragit et de la charge initiale en insuline. Conclusion : Cette etude a montre que la matrice Ethylcellulose/Eudragit se prete a la mise au point d'un systeme a liberation controlee d'insuline. Ceci nous permet d'envisager pour la poursuite de notre travail l'association de cette matrice avec d'autres elements pour la realisation d'un STTLC de l'insuline

Antidiabetic properties of aqueous barks extract of Parinari excelsa in alloxan-induced diabetic rats.

The aqueous extract of the Parinari excelsa barks at doses of 100 and 300 mg/kg/day for 7 days has a significant antihyperglycemic effect on alloxan-induced diabetic rats. At the same dose the acute oral administration of aqueous extract of the P. excelsa barks (100 and 300 mg/kg) induced a significant decrease of blood glucose on glucose-loaded normoglycaemic rats. Our results seem to confirm the rational bases for its use in traditional medicine.

[Culture and characterization of porcine coronary endothelial cells]. / Culture et caractérisation des cellules endothéliales d'artère coronaire de porc.

INTRODUCTION: Vascular endothelium possesses biological properties that are involved in important physiological functions such vascular permeability, vascular tone regulation and angiogenesis. The difficulty of culture and long-term maintenance of sufficient amount of normal endothelial cells has proven to be the limitation for the understanding of the biological function of the endothelium. Therefore, the aim of this study was to culture and characterize the porcine coronary endothelial cells. MATERIAL AND METHODS: The endothelial cells were isolated by collagenase treatment and cultured in culture dishes coated with collagen, prepared from rat tail, containing medium RPMI1640/M199 and 15% fetal calf serum supplemented with antibiotics and fungizon. The cells were maintained to grown at 37 degrees C. The medium was changed one day after and then every two day. The cells were incubated with Dil-labeled-acetylated-LDL for determination of acetylated-LDL uptake. Confluence cultures of cells were examined by phase-contrast and confocal microscopy. RESULTS: After a day of culture, the endothelial cells adhere to the collagen and began to grow. While multiplying themselves, they colonize little by little the body of the surface of culture to form to confluence a monolayer of flat cells relatively homogenous. To confluence, the proliferation of the endothelial cells is inhibited by the contact and the cells present a polygonal aspect. Our results show that all the cultivated cells were strongly positive for acetylated-LDL markers. The endothelial cells, cultivated until the second passage corresponding to the second culture of the primary cultures, continued to present a good fluorescence. CONCLUSION: Porcine coronary endothelial cells represent a useful in vitro model to study biological and physiopathological properties of vascular endothelium.

[Experimental evidence of against cough activity of total alkaloids from Guiera senegalensis Lam. in guinea pig;]. / Mise en evidence de l'activité antitussive des alcaloïdes totaux de Guiera senegalensis Lam. chez le cobaye.

INTRODUCTION: Against cough activity from Guiera senegalensis' leaves has been previously scientifically studied. However, to the best of our knowledge, active principles responsible of this activity were not yet identified. Thus, we undertook this work with the aim to evaluate the effect of total alkaloids from plant's leaves in cough induced in guinea pig by ammoniac inhalation. MATERIAL AND METHODS: Guinea pigs were divided up in 5 groups of 10 and were crammed with distilled water (control), total alkaloids with 10, 25 and 30 mg/kg and codeine with 50 mg/kg. They were then exposed to ammoniac inhalations and the number of coughs was counted every hour, after cramming, during 5 min. RESULTS: Our results show, after 5 hours, with the doses of 15, 25 and 30 mg/kg per os, that total alkaloids induce against cough activity, 2 hours after cramming (p < 0.01) and the difference was still significant 3, 4 and 5 hours after (p < 0.001). These alkaloids effects were comparable with codeine activity which was used as reference product. CONCLUSION: Total alkaloids of Guiera senegalensis present an against cough activity and would be responsible of against cough activity of the plant.

Culture et caracterisation des cellules endotheliales d'artere coronaire de porc

Introduction : Les proprietes biologiques de l'endothelium vasculaire lui conferent un role majeur dans le controle de la permeabilite; du tonus vasculaire et l'angiogenese; des fonctions physiologiques cruciales a l'homeostasie vasculaire. La comprehension du ou des mecanisme(s) d'action sous-jacent(s) a ces multiples proprietes a longtemps ete retardee par la difficulte technique d'obtenir des quantites suffisantes de ce tissu permettant de realiser les etudes in vitro. Ce travail a pour objectif de proceder a la mise en culture et a la caracterisation des cellules endotheliales d'artere coronaire de porc. Materiels et Methodes : La couche de cellules endotheliales a ete prelevee par passage de la solution de collagenase a travers la lumiere du vaisseau. Les cellules ont ete ensuite ensemencees dans des flacons de culture; prealablement recouverts de collagene de queue de rat dans un milieu de culture RPMI1640/M199 auquel a ete rajoute 15de serum de veau fotal; des antibiotiques et de la fungizone. Les cultures ont ete maintenues a 37oC dans un incubateur. La sonde fluorescente constituee de lipoproteines acetylees de faible densite (Dil-Ac-LDL) a ete utilisee comme marqueur biologique specifique par recapture par les cellules endotheliales. Les cellules confluentes ont ete repiquees dans des chambres de culture LAB-TEK puis examinees au microscope photonique et confocal. Resultats : Apres 24 heures de mise en culture; les cellules endotheliales adherent au collagene et forment des rosettes. En se multipliant; elles colonisent peu a peu l'ensemble de la surface de la boite de culture pour former a confluence un tapis pavimenteux relativement homogene. A confluence; la proliferation des cellules endotheliales est inhibee par le contact et elle presente un aspect polygonal. Nos resultats montrent que les cellules cultivees presentent un intense marquage au Dil-Ac-LDL. Conclusion : Les cellules endotheliales de l'artere coronaire de porc en culture constituent un bon outil pour l'etude des fonctions endotheliales dans des conditions physiologiques et pathologiques.Introduction : Les proprietes biologiques de l'endothelium vasculaire lui conferent un role majeur dans le controle de la permeabilite; du tonus vasculaire et l'angiogenese; des fonctions physiologiques cruciales a l'homeostasie vasculaire. La comprehension du ou des mecanisme(s) d'action sous-jacent(s) a ces multiples proprietes a longtemps ete retardee par la difficulte technique d'obtenir des quantites suffisantes de ce tissu permettant de realiser les etudes in vitro. Ce travail a pour objectif de proceder a la mise en culture et a la caracterisation des cellules endotheliales d'artere coronaire de porc. Materiels et Methodes : La couche de cellules endotheliales a ete prelevee par passage de la solution de collagenase a travers la lumiere du vaisseau. Les cellules ont ete ensuite ensemencees dans des flacons de culture; prealablement recouverts de collagene de queue de rat dans un milieu de culture RPMI1640/M199 auquel a ete rajoute 15de serum de veau fotal; des antibiotiques et de la fungizone. Les cultures ont ete maintenues a 37oC dans un incubateur. La sonde fluorescente constituee de lipoproteines acetylees de faible densite (Dil-Ac-LDL) a ete utilisee comme marqueur biologique specifique par recapture par les cellules endotheliales. Les cellules confluentes ont ete repiquees dans des chambres de culture LAB-TEK puis examinees au microscope photonique et confocal. Resultats : Apres 24 heures de mise en culture; les cellules endotheliales adherent au collagene et forment des rosettes. En se multipliant; elles colonisent peu a peu l'ensemble de la surface de la boite de culture pour former a confluence un tapis pavimenteux relativement homogene. A confluence; la proliferation des cellules endotheliales est inhibee par le contact et elle presente un aspect polygonal. Nos resultats montrent que les cellules cultivees presentent un intense marquage au Dil-Ac-LDL. Conclusion : Les cellules endotheliales de l'artere coronaire de porc en culture constituent un bon outil pour l'etude des fonctions endotheliales dans des conditions physiologiques et pathologiques

Mise en evidence de l'activite antitussive des alcacoides totaux de Gueira Senegalensis Lam. chez le cobaye

Introduction : L'activite antitussive des feuilles de Guiera senegalensis a deja fait l'objet d'etudes scientifiques. Cependant; a notre connaissance; les principes actifs responsables de cette activite n'ont pu etre identifies a ce jour. C'est pour pallier cette insuffisance que nous avons effectue cette etude afin d'evaluer l'effet des alcaloides totaux des feuilles de la plante; sur la toux provoquee chez le cobaye; par inhalation de vapeurs d'ammoniac. Materiel et Methodes : Les cobayes repartis en 5 lots de 10 ont ete gaves avec de l'eau distillee (temoins); les alcaloides totaux aux doses de 15; 25 et 30 mg/kg et la codeine a 50 mg/kg. Ils ont ete ensuite exposes a des vapeurs d'ammoniac et le nombre d'acces de toux est compte toutes les heures; apres le gavage; pendant 5 min. Resultats : Il ressort de l'etude qui aura dure 5 heures; qu'aux doses de 15 mg/kg; 25 mg/kg et 30 mg/kg de poids corporel; par voie orale; les alcaloides totaux provoquent une diminution significative du nombre des acces de toux par rapport au temoin; des la deuxieme heure de mesure (p0;01) ; cette difference est restee significative aux troisieme; quatrieme et cinquieme heures (p0;001). Ces effets des alcaloides totaux sont comparables a celui de la codeine utilisee comme antitussif de reference. Conclusion : Les alcaloides totaux des feuilles de Guiera senegalensis presentent une activite antitussive et seraient responsables de l'effet antitussif de la plante

[Mechanisms of action of acetonic and hexanic extracts of leaves of Vernonia colorata (Willd.) Drake (Composeae) on blod glucose regulation]. / Mecanismes d'action des extraits acetonique et hexanique de feuilles de Vernonia colorata dans la regulation de la glycemie.

INTRODUCTION: This study aimed to investigate the mechanism of action of acetonic and hexanic extracts of the leaves of Vernonia colorata on blood glucose regulation. MATERIALS AND METHODS: Experiments were performed in normoglycaemic, type 1 and 2 diabetic rats. The effects of acetonic and hexanic extracts on blood glucose were evaluated. The antagonism effect of hexanic extract on the decrease of blood glucose induced with glibenclamide and metformin was also tested. RESULTS: The hexanic extract of the leaves of V. colorata (HELVC) dose dependently increased the blood glucose in normoglycaemic rats. At the dose of 30 and 100 mg/kg, the glycaemia varied from 0.84 +/- 0.02 to 1.11 +/- 0.10 g/l and 0.68 +/- 0.02 to 1.31 +/- 0.30 g/l (p<0.05, n = 5). Such glibenclamide, the acetonic extract of the leaves of V. colorata (AELVC) induced hypoglycaemia in normoglycaemic rats. The HELVC prevents significantly the AELVC and glibenclamide induced hypoglycaemia. The chronic administration of the AELVC and HELVC as well as glibenclamide in type 1 diabetic rats did not change significantly the level of blood glucose. In type 2 diabetic rats, the single dose administration of metformin (300 mg/kg, per os) decreased the glycaemia which is completely prevented by a HELVC pretreatment. CONCLUSION: These results suggest that: i) The respective hypo- and hyperglycaemic effects of AELVC and HELVC require the presence of the pancreatic beta cells. ii) The AELVC would act by a sulfonylurea-like mechanism as glibenclamide to induce an hypoglycaemic effect.

[Healing activity of methanolic extract of the barks of Spathodea campanulata Beauv (Bignoniaceae) in rat experimental burn model]. / Activite cicatrisante de l'extrait methanolique des ecorces de Spathodea campanulata Beauv (Bagnoniaceae) sur un modele de brulures experimentales chez le rat.

Spathodea campanulata Beauv. (Bignoniaceae) is widely distributed through Africa and found in particular in Cameroon and Senegal. It is used in traditional herbal medicine for the treatment of ulcers, filaria, gonorrhea, diarrhea and fever. S. campanulata was also known in Cameroon traditional medicine to have a healing activity in burn wounds. The aim of the present study was to assess the burn healing effectiveness of the methanolic extract of the barks of S. campanulata ointment (MEBSCO) in comparison to those of Centella asiatica and Peru's balm in experimental burn model in rats. Experimental burn was made in rat under chloral anaesthesia with electric iron (200 degrees C) on the right and left side of the medianus line. Topical applications of MEBSCO (2%, 10% and 49%) dose-dependently decreased the score damage of the burn site. Treatment with 10% and 49% of MEBSCO varied the score damage from 5 to 1 +/- 0.4 and 5 to 0.2 +/- 0.5 (p < 0.05, n = 5) respectively, at day 15 after experimental burn. As well as C. asiatica (1%) and Peru's balm (1%) ointments, MEBSCO (10% and 49%) induced a complete burn healing on the 19-20th post burn day. This study shows for the first time, the burn healing effectiveness of MEBSCO in experimental burn model. It also provides a rational use of the S. campanulata barks in traditional medicine to promote burn healing.

[Prescription and use of benzodiazepins in Saint-Louis in Senegal: patient survey]. / Evaluation de la prescription et de l'utilisation des benzodiazépines dans la commune de Saint-Louis du Sénégal: enquête auprès des patients.

Prescription and use of benzodiazepins were evaluated with a patients survey. Direct interview were conducted with 150 patients in ten pharmacies in the city of Saint-Louis, Senegal from January to June 2002. Ten of the 15 retail pharmacies in this city agreed to participate in the survey. All patients gave their agreement to participate to the study; the questionnaire contained essentially closed questions. Writers of prescriptions were general practitioners (38.67%), specialists (34.67%), nurses (18%) and midwifes (8.66%). The most prescribed benzodiazepins were prazepam, dipotassic clorazepate, lorazepam and diazepam. Use of these drugs during night is most recommended. Nevertheless, 26.67% of the prescriptions indicated the drug should be use during the day. The period of use was between one and three Months for 33.99% of patients and three Months or more in 42%. Benzodiazepins were used by 66.67% for insomnia, alone or associated with another condition, for anxiety by 14.6% and for epilepsy by 10%. Prescriptions were for benzodiazepins alone in 47.37% of the patients and in combination with other psychotropic drugs for 19.33%. Somnolence and dependence were the most reported side effects.

[Effectiveness of syndromic approach for management of urethral discharge in Senegal]. / Evaluation de l'efficacité du traitement des écoulements urétraux au Sénégal selon l'approche syndromique.

The World Health Organization has proposed the syndromic approach for management of sexually transmissible diseases (STD) in countries where diagnostic laboratory tests are not consistently available. The purpose of this study was to evaluate the effectiveness of this approach for treatment of ureteral discharge in Senegal. Twenty seven men presenting ureteral discharge underwent two-week treatment using a combination of cotrimoxazole plus tetracycline for suspected gonococcal and a chlamydial infections. Ureteral samples were collected before and after treatment to detect Neisseria gonorrhoeae by culture and Chlamydia trachomatis by direct immunofluorescence and ELISA. Results demonstrated successful treatment of all patients presenting gonococcal and chlamydial infections i.e. 84.6% of cases. Neither germ was detected in 15.4% of cases. Before treatment, Neisseria gonorrhoeae, Chlamydia trachomatis or both were found respectively in 53.9%, 5.1% and 25.6% of samples respectively. Based on these findings we conclude that the syndromic approach was effective in 84.6% of cases but treatment was in adequation with STD biologically documented only with 25.6% of cases.

[Antipyretic effect of aqueous extract and alcaloid of Tinospora bakis (Miers) in rabbits]. / Effet antipyrétique de l'extrait aqueux et des alcaloïdes de Tinospora bakis (A. Rich.) Miers (Menispermacea) chez le lapin.

Lyophilised aqueous extract and alcaloidic totum (basic form) from roots of Tinospora bakis (Miers) have been tested with hyperthermic rabbits by sub-cutaneous administration of Saccharomyces cerevisiae mixture at 2g/kg. Total aqueous extract had been orally administrated at three doses: 150, 300 and 600 mg/kg and we obtained significant antipyretic effects at 300 and 600 mg/kg. With the alcaloidic totum at 2.5 mg/kg and 10 mg/kg (per os) corresponding to 150 and 600 mg/kg of the aqueous extract, we have observed significant antipyretic effects as compared with those of Aspirin used as reference product. These results show that aqueous extract of Tinospora bakis (Miers) has an antipyretic effect and total alcaloids could account for this activity.

[Contribution to the study of the anti-inflammatory activity of Moringa oleifera (moringaceae)]. / Contribution a l'etude de l'activite anti-inflammatoire de moringa oleifera (moringaceae).

Moringa oleifera is a bush of African savannah, used in folk Medicine for the treatment of rheumatic and articulary pain. We have tested the anti-inflammatory action of an aqueous extract of root in rats with weight between 120 and 160 g. We administered per os either distilled water (control group), the aqueous root extract (750 mg/kg or 1000 mg/kg) or indomethacin (10 mg/kg) 30 min before an oedema was induced in the rat-paw by subcutaneous injection of carrageenin. The rat-paw volume was measured 1, 3 and 5 hours after injection of carrageenin. At a dose of 750 mg/kg the Moringa oleifera treatment significantly inhibited the development of oedema at 1, 3 and 5 hours (reduction by 53.5, 44.6 and 51.1% respectively). Increasing the dose of Moringa oleifera to 1000 mg/kg did not increase the inhibitory effect on oedema development at 1 and 3 hours, whereas this dose potentiated the oedema at 5 hours. Treatment with indomethacin significantly inhibited the development of oedema 1, 3 and 5 hours (49.1, 82.1 and 46.9% respectively). These findings indicate that an aqueous root extract of Moringa oleifera at 750 mg/kg reduces the carrageenin induced oedema to similar extent as the potent anti-inflammatory drug indomethacin. Moreover, these results provide further evidence that the roots of Moringa oleifera contain anti-inflammatory principle that may be useful in the treatment of the acute inflammatory conditions.

[Which basal tension for the study of aortic reactivity in pregnant Wistar rats?]. / Quelle tension de base pour l'etude de la reactivité aortique chez la rate Wistar gestante?

Basal tension for optimal contraction either for a maximal contraction in pregnant Wistar rat is not well know. Our study aims to determinate the optimal basal tension for the study of aortic contraction in pregnant Wistar rat. The stability of vessels tone depending on basal tension was also determinate. Aortic rings with endothelial cells from non-pregnant and 20-day pregnant Wistar rats were used. Rings with different basal tensions of 1 g, 1.5 g, 2 g or 2.5 g were contracted with KCl at 100 mmol/l or norepinephrine in a cumulative manner (10-9M à 3.10-5M). Our results show, at least, one hour of stability for all basal tensions. On the other hand, contractions raise in a significant manner depending in basal tension either with KCl or norepinephrine. However, There is no significant difference in contractions with the basal tensions of 2 g and 2.5 g except in pregnant rats where vessels were contracted with norepinephrine. These results suggest that basal tension of 2 g would be used for the study of aortic reactivity in pregnant Wistar rat because it allows a good stability, the tension is practically optimal in pregnant and non-pregnant rats with any contracting agent and this tension is most commonly used.

[Endothelium-dependent relaxation of Wistar rat aorta in late pregnancy]. / Relaxation endothélio-dépendante de l'aorte de la rate Wistar en fin de gestation.

Some authors usually described an enhanced vascular reactivity to vasodilatoragents during pregancy. We would like toverifythis hypothesis with acetylcholin which is the vasodilator agent habitually used in animal experimentation. Young adult Wistar rats, pregnant and nonpregnant, were used. Rats received either a control diet, or this control diet supplemented with nitroargininin (0.063 % i.e. 30 mg/kg for7 days [treated group], from day 13th to day 20th for pregnants. Relaxation of rings thoracic aorta, with or without endothelium, in the presence of acetylcholin in cumulative was studied after contraction induced by depolarisation with KCl or after noradrenalin addition. The results show that relaxation in the presence of acetylcholin needs functional endothelial cells and that the nitric oxide plays a key role in this relaxation. So, there is no difference in vascular reactivity in late pregnant rats compared to nonpregnant rats. In addition, chronic inhibition of nitric oxide synthesis in pregnant rats do not modify pregnancy reactivity to nitric oxide because relaxation to S-nitroso-N acetyl penicillamin, which is a nitric oxide donor, is not different in control pregnant rats compared to treated pregnant rats. A judicious observation of work conditions with a particular attention with calcium concentration in organ bath solutions would certainly explain contradictory results obtained by different authors on vascular reactivity in vitro during gestation.

Endothelium and aortic contraction to endothelin-1 in the pregnant rat.

Endothelium-derived factors modulate tone and may be involved in hyporeactivity to vasoconstrictors, such as norepinephrine or angiotensin II, as has been previously described during gestation. The endothelium produces endothelin-1, a major vasoconstrictor peptide, therefore aortic contractions to endothelin-1 (10(-10) to 3 x 10(-7) M) were used to assess the role of the endothelium in pregnant Wistar rats (at 20 days of gestation). Late pregnancy is characterized by a significantly diminished systolic blood pressure in conscious rats (-17 mmHg, P < 0.001, n = 14). In pregnant and in age-matched nonpregnant female rats, endothelin-1 induced aortic contraction was greater when endothelium was present (at least P < 0.01). Indomethacin significantly reduced this contraction in aortic rings with intact endothelium in all groups. In aortic rings that had endothelium physically removed, contraction to endothelin-1 was greater in pregnant rats than in nonpregnant ones. Indomethacin decreased contraction of aortic rings in pregnant rats only. These results suggest an enhanced synthesis of vasoconstrictors by cyclooxygenases in vascular smooth muscle during pregnancy. In vessels with intact endothelium, we did not find hyporeactivity to endothelin-1 during late pregnancy. Contraction to endothelin-1 involved ET(A) receptors because it was decreased by BQ-123, an ET(A) receptor antagonist, whereas there was no significant change when using BQ-788, an ET(B) receptor antagonist.