Estrous cycle variation in anxiolytic-like effects of topiramate in Wistar rats in two animal models of anxiety-like behavior.

The anxiolytic-like effects of topiramate were assessed during several estrous cycle phases in Wistar rats tested in two animal models of anxiety-like behavior. In a conflict operant test, during proestrus, diazepam (1.3, 2.0mg/kg; P<0.05) or topiramate (20.0, 30.0mg/kg; P<0.05) increased the number of immediately punished responses. During metestrus-diestrus only the highest doses of diazepam (2.0mg/kg, P<0.05) or topiramate (30.0mg/kg, P<0.05) increased the number of immediately punished reinforcers. Similar results were obtained in the elevated plus-maze test: during proestrus, diazepam (1.3, 2.0mg/kg; P<0.05) or topiramate (20.0, 30.0mg/kg; P<0.05) produced anxiolytic-like actions. During metestrus-diestrus only the highest doses of diazepam (2.0mg/kg, P<0.05) or topiramate (30.0mg/kg, P<0.05) produced anxiolytic-like actions. Neither diazepam nor topiramate nor estrous cycle phases significantly modified the number of closed arm entries in the elevated plus-maze test. It is concluded that the response to neuromodulatory drugs for anxiety-like behavior varied according to the estrous cycle phases.

Intra-lateral septal infusions of folic acid alone or combined with various antidepressant drugs produce antidepressant-like actions in male Wistar rats forced to swim.

Intra-cerebral administrations of folic acid produce antidepressant-like effects; either alone or combined with several antidepressant drugs. However, the specific limbic structures implied in the antidepressant-like actions of folic acid are un-known. Thus, intra-lateral septal infusions of folic acid (5.0 nmol, P<0.05; 10.0 nmol, P<0.05) or oral administrations of folic acid (50 mg/kg, P<0.05, p.o.; 75.0; mg/kg, P<0.05, p.o.) or systemic administrations of fluoxetine (20.0 mg/kg, P<0.05; 25.0 mg/kg, P<0.05) reduced immobility by increasing swimming behavior in the forced swimming test (FST) of male Wistar rats. Conversely, desipramine (10.0 mg/kg, P<0.05; 15.0 mg/kg, P<0.05) reduced immobility by increasing climbing behavior. Subthreshold doses of folic acid (2.5 nmol/intra-LSN) combined with subthreshold doses of folic acid (25.0 mg/kg, p.o., P<0.05) or with subthreshold doses of fluoxetine (15.0 mg/kg, P<0.05) and they produced antidepressant-like effects which were canceled by ketanserin. In conclusion, intra-lateral septal infusions of folic acid alone or combined with systemic doses of folic acid or fluoxetine reduced immobility in the FST. These antidepressant-like actions, probably, were due to modifications of the serotonergic system since swimming behavior was increased and these effects were canceled by ketanserin.

Fluoxetine, 17-ß estradiol or folic acid combined with intra-lateral septal infusions of neuropeptide Y produced antidepressant-like actions in ovariectomized rats forced to swim.

Folic acid is antidepressant, either alone or combined with several antidepressant drugs. However, the antidepressant-like actions of folic acid combined with intra-lateral septal (LSN) infusions of neuropeptide Y (NPY) in the forced swimming test (FST) have not been tested before. Thus, systemic injections of fluoxetine (20.0mg/kg, P<0.05; s.c.) or 17-ß estradiol (10.0 µg/rat, P<0.05; s.c.) or oral administrations of folic acid (50.0 mg/kg, P<0.05; 75.0 mg/kg, P<0.05) or NPY intra-LSN (3.0 µg, P<0.05; 3.5 µg, P<0.05) reduced immobility of ovariectomized Wistar rats. Subthreshold doses of: folic acid (25.0 mg/kg) or 17-ß estradiol (5.0 µg/rat, P<0.05) or fluoxetine (15.0 mg/kg, P<0.05; s.c.) combined with subthreshold doses of NPY (2.5 µg/rat, P<0.05; intra-LSN) and these combinations produced antidepressant-like actions; which were canceled by BIBP 3226 (a NPY-Y1 receptor antagonist). It is concluded that folic acid produced antidepressant-like effects probably through the participation of the NPY Y1 receptors found in the lateral septal nuclei.

Antidepressant-like or anxiolytic-like actions of topiramate alone or co-administered with intra-lateral septal infusions of neuropeptide Y in male Wistar rats.

We tested the effects of intra-lateral septal infusions of neuropeptide Y (NPY) combined with systemic injections of topiramate in the DRL-72s paradigm and the elevated plus-maze test in male Wistar rats. Intra-lateral septal infusions of desipramine (5.0 microg/microl; P<0.05) or intra-lateral septal infusions of NPY (3.0 microg/microl, P<0.05; 3.5 microg/microl, P<0.05) or systemic injections of topiramate (20.0mg/kg, P<0.05; 30.0mg/kg, P<0.05) or subthreshold doses of topiramate (10.0mg/kg) combined with intra-lateral septal infusions of subthreshold doses of NPY (2.5 microg/microl; P<0.05) induced a dose-dependent increase in reinforced lever presses and a cohesive rightward shift of the inter-response time distribution in the DRL 72s task. In the elevated plus-maze test, intra-lateral septal infusions of NPY (3.0 microg/microl, P<0.05; 3.5 microg/microl, P<0.05) or midazolam (10.0 microg/microl; P<0.05) or systemic injections of topiramate (20.0mg/kg, P<0.05; 30.0mg/kg, P<0.05) or subthreshold doses of systemic injections of topiramate (10.0mg/kg) combined with intra-lateral septal infusions of subthreshold doses of NPY (2.5 microg/microl; P<0.05) increased the exploration of the open arms without affecting locomotion. In conclusion, intra-septal NPY has anxiolytic effects in the EPM, and antidepressant effects in the DRL 72s test. Similarly, systemic topiramate has anxiolytic effects in the EPM, and antidepressant effects in the DRL 72s test. Finally, a combination of subthreshold doses of NPY and topiramate together also have anxiolytic and antidepressant effects, suggesting a synergistic effect.

Olanzapine plus 17-beta estradiol produce antidepressant-like actions in rats forced to swim.

Several combinations of effective treatments have been used in the search for higher response rates or more rapid responses than monotherapy to diminish treatment-resistant depression. One strategy is to combine olanzapine plus antidepressant drugs. In preclinical studies in male rats, olanzapine combined with fluoxetine produce antidepressant-like actions and increase the allopregnanolone levels in the brain. 17-beta estradiol also produces antidepressant-like actions by increasing allopregnanolone levels. However, the effects of combining olanzapine with 17-beta estradiol in the forced swimming test have not been tested before. Thus, systemic injections of vehicle plus olanzapine, or fluoxetine (20.0 mg/kg; 25.0 mg/kg) or 17-beta estradiol (10.0 microg/rat; 20.0 microg/rat) reduced immobility by increasing active behaviors, which were cancelled by finasteride (finasteride was used to block the endogenous production of allopregnanolone by the brain) in ovariectomized rats forced to swim. Subthreshold doses of olanzapine (2.5 mg/kg) combined with subthreshold doses of 17-beta estradiol (5.0 microg/rat) produced antidepressant-like actions, as did the combination subthreshold dose of olanzapine (2.5 mg/kg) plus the subthreshold dose of fluoxetine (15.0 mg/kg). Finasteride cancelled the antidepressant-like actions of the several combinations used. It is concluded that olanzapine alone or combined with fluoxetine or estradiol reduced immobility by increasing swimming. In conclusion, olanzapine produces antidepressant-like actions alone or in combination with estradiol. These antidepressant-like actions of this combination were cancelled by finasteride.

Estradiol and neuropeptide Y (intra-lateral septal) reduce anxiety-like behavior in two animal models of anxiety.

Anxiolytic-like effects of intra-lateral septal nuclei (LSN) infusions of the neuropeptide Y (NPY) alone or combined with estradiol benzoate were assessed in ovariectomized Wistar rats in two animal models of anxiety-like behavior. In a conflict test, immediately punished responses were assessed: 17-beta-estradiol (50.0microg/rat, P<0.05) plus vehicle (intra-LSN) or intra-LSN infusions of NPY (2.5microg/microl, P<0.05; 3.0microg/mul, P<0.05) plus vehicle (systemic route) or the combination of subthreshold doses of 17-beta-estradiol (25.0microg/kg) plus intra-LSN infusions of NPY (2.0microg/mul, P<0.05) increased the amount of immediately punished reinforcers. In the elevated plus-maze test several spatial-temporal variables were evaluated: 17-beta-estradiol (50.0microg/kg, P<0.05) plus vehicle (intra-LSN) or intra-LSN infusions of NPY (2.5microg/mul, P<0.05; 3.0microg/mul, P<0.05) plus vehicle (systemic route) or the combination of subthreshold doses of 17-beta-estradiol (25.0microg/kg) plus intra-LSN infusions of NPY (2.0microg/mul, P<0.05) produced anxiolytic-like actions without affecting locomotion. It is concluded that estradiol or NPY may produce anxiolytic-like actions and that subthreshold doses of estradiol and subthreshold doses of NPY when combined produced anxiolytic-like actions.

Estrus variation in anxiolytic-like effects of intra-lateral septal infusions of the neuropeptide Y in Wistar rats in two animal models of anxiety-like behavior.

Anxiolytic-like effects of intra-lateral septal infusions of the neuropeptide Y (NPY) were assessed during several estrus phases in Wistar rats tested in two animal models of anxiety-like behavior. In a conflict operant test, results showed that during late proestrus, intra-lateral septal nuclei infusions of NPY (1.0 microg/microl, P<0.05; 2.0 microg/microl, P<0.05; 2.5 microg/microl, P<0.05) increased the number of immediately punished responses. During metestrus-diestrus only the highest doses of NPY (2.5 microg/microl, P<0.05) increased the number of immediately punished reinforcers. In the elevated plus-maze test, results showed that during late proestrus, intra-lateral septal nuclei infusions of NPY (1.0 microg/microl, P<0.05; 2.0 microg/microl, P<0.05) produced anxiolytic-like actions. During metestrus-diestrus only the highest doses of NPY (2.0 microg/microl, P<0.05) produced anxiolytic-like actions. Neither NPY nor estrus phases significantly modified the number of closed arms entries in the elevated plus-maze test. It is concluded that anxiolytic-like effects of NPY vary within the estrus cycle in Wistar rats.

Anxiolytic-like actions of leaves of Casimiroa edulis (Rutaceae) in male Wistar rats.

Anxiolytic-like actions of an aqueous extract of the leaves of Casimiroa edulis (Ce) La Llave ex Lex. (Rutaceae) were studied in male Wistar rats in the elevated plus-maze test, whether effect on locomotion were studied in the open-field task, and its possible antidepressant-like actions in the forced swimming task. In the elevated plus-maze test, diazepam (Dz) (1.30 mg/kg; P < 0.05) and Casimiroa edulis (25.0 mg/kg, P < 0.05; 35.0 mg/kg, P < 0.05) increased open arms exploration (i.e., anxiolytic-like action). Doses of 45.0 mg/kg (P < 0.05) and 55.0 mg/kg (P < 0.05) of Casimiroa edulis reduced locomotion in the elevated plus-maze test and in the open-field test. In the forced swimming task, desipramine (dmi) (32.0 mg/kg; P < 0.05) reduced immobility (i.e., antidepressant-like action). Conversely, as compared to control rats, neither diazepam (Dz) (1.30 mg/kg) nor Casimiroa edulis (25.0 mg/kg) modified immobility in the forced swimming task. However, diazepam (P < 0.05) or Casimiroa edulis (P < 0.05), when co-administered, canceled the antiimmobility actions of desipramine. In conclusion, the leaves of Casimiroa edulis (Rutaceae) produced anxiolytic-like actions in male Wistar rats, with several side actions, namely, reduced locomotion and neutralization of the antidepressant-like actions of desipramine.

Anti-conflict-like actions of intralateral septal infusions of allopregnanolone in Wistar rats.

The aim of the present study was to test the hypothesis that allopregnanolone infused into the lateral septal nuclei will reduce conflict-like behavior in ovariectomized rats. The interaction with systemic administration of several agonists and antagonists of the GABA-A receptor was assessed. Results showed that intralateral septal doses of allopregnanolone (1.0 microg, P<.05; 2.0 microg, P<.05) or systemic injections of allopregnanolone (1.0 mg/kg s.c., P<.05; 2.0 mg/kg s.c., P<.05), diazepam (2.0 mg/kg i.p., P<.05), or muscimol (0.3 mg/kg i.p., P<.05; 0.6 mg/kg i.p., P<.05) reduced conflict-like behavior. Subthreshold doses of intralateral septal infusions of allopregnanolone (0.5 microg/side) synergized with systemic subthreshold doses of GABA-A agonists: allopregnanolone (0.5 mg/kg, P<.05), diazepam (1.5 mg/kg, P<.05), or muscimol (0.1 mg/kg, P<.05). The GABA-A antagonists, flumazenil (0.1 mg/kg i.p.) and bicuculline (2.0 mg/kg i.p.) attenuated the synergism between intralateral septal infusions of allopregnanolone and diazepam or muscimol, respectively. Conversely, neither flumazenil (P<.05) nor bicuculline (P<.05) attenuated the synergism of the combination allopregnanolone (intralateral septum nuclei; 0.5 microg/side) plus systemic injections of allopregnanolone. In conclusion, allopregnanolone reduced conflict-like behavior probably acting at the GABA-A receptors found in the lateral septal nuclei.

Antidepressant-like actions of pregnancy, and progesterone in Wistar rats forced to swim.

In rats, some behavioral changes occurring during pregnancy related to the presence of progesterone may be analyzed in the forced swimming task (FST), which is designed to test the antidepressant profile of drugs. The present study was aimed to analyze in pregnant rats, in rats after delivery, or in rats after receiving progesterone those behavioral changes displayed in the FST. We hypothesize that pregnancy and progesterone will produce antidepressant-like effects in rats forced to swim. Therefore, pregnant rats (14th, 17th, and 20th days), or rats after delivery (3rd, and 7th days) were tested in the FST. Ovariectomized rats receiving saline (0.9%; i.p.), clomipramine (1.25 mg/kg; i.p.), or desipramine (2.14 mg/kg; i.p.) for 28 days were also tested in the FST. In a second series of experiments, ovariectomized rats receiving vehicle or progesterone (0.5 mg/kg; or 2.0 mg/kg; sc.) were tested in the FST. Locomotion was evaluated in the open field test. Results showed that in the FST: 1) pregnancy (P < 0.05), or progesterone (P < 0.05), or desipramine (P < 0.05), reduced immobility by increasing climbing; 2) clomipramine (P < 0.05) reduced immobility by increasing swimming; 3) rats tested after delivery displayed similar behavior than control rats. A lower locomotion was observed only at the end of pregnancy. In conclusion, results suggest that during pregnancy, a reproductive process characterized by its high levels of progesterone, antidepressant-like effects can be found.

Estrus variation in anticonflict effects of midazolam microinjected into septal nuclei in female Wistar rats.

Effects of midazolam intraperitoneally (3.0 mg/kg) administered, or locally applied into lateral septal nuclei (10 microg/microl), or into the medial septum (10 microg/microl) were assessed in Wistar rats during late proestrus or metestrus-diestrus in a conflict-operant task. A reduction in conflict behavior was found in control rats during late proestrus (P<.05), when compared to metestrus-diestrus. Systemic injections of midazolam (P<.05) or midazolam infusions into lateral septal nuclei (P<.05) also reduced conflict behavior only during late proestrus, whereas midazolam infusions into the medial septum produced neither of these anticonflict effects in any estrous phase. In conclusion, an endocrine-related variation in anticonflict effects of midazolam microinjected into lateral septal nuclei was displayed by female rats.

Environmental contamination by Toxocara sp eggs in public areas of Salvador, Bahia State, Brazil.

A survey of parasite eggs and cysts in soil and dog feces collected in public places of 23 boroughs of Salvador, a city in the Northeast of Brazil, was performed. High degree of contamination by Toxocara sp eggs was observed in all boroughs studied; other parasites found included: Ascaris lumbricoides, hookworms, whipworms and protozoan cysts. Parks and public gardens were more contaminated than streets and beaches for all parasites, including Toxocara sp.

[Epidemiology of tegumentary American leishmaniasis and its relations with agriculture and prospecting, in a locality of the State of Bahia, Brazil]. / Epidemiologia da leishmaniose tegumentar americana e suas relações com a lavoura e o garimpo, em localidade do Estado da Bahia (Brasil).

This study was carried out in the city of Lençóis, State of Bahia, with the objective of verifying the association between leishmaniasis infection and occupation. A Montenegro test and a questionnaire including biological and socio-economic variables were applied to the study group. Sandflies were captured in and around dwellings. The higher-than-average prevalence of leishmaniasis observed among agricultural workers and prospectors is explained by the double exposure to the infection-both at home and at work.