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C Valerio

Publications and source records attributed to C Valerio.

At least 37 records · Page 2Linked to original sources
PubMed1992

Hysterical personality and family: a clinical case.

Within the framework of family typology, the therapist can organize and orient his own observations, by confronting the characteristics of a particular family system, with the models of a "shared reality". Structural and organizational analysis of the family system, according to a general typology, can also be useful when the therapist has to deal with a defined and a not specific symptom or disease, and when a differential diagnosis is necessary for its pragmatic effects. This is often the case of hysteria, which according to many authors can show today various, confused shapes, as depression, general existential discomfort, anorexia and bulimia, and forms of exhibited addition. The authors present a clinical case, trying to point out how a "typology-oriented" observation of the family system, allowed the therapists to clarify an individual condition, otherwise difficult to understand.

Adult↗
PubMed1992

[Cerebral actions of dihydroergocristine].

Dihydroergocristine (DEC, CAS 17479-19-5) is a dihydrogenated ergot alkaloid with a potent dopaminergic activity that has been proved both in vitro and in vivo. Apart from its effect on the secretion of pituitary hormones, the following actions have been evidenced. It induces stereotyped behaviour and changes in the sleep-waking cycle, and reduces hypoxia-induced cerebral metabolic changes and emesis. The effect of DHEC on behaviour patterns has been studied in aged male rats in comparison with young animals. The acquisition of the active avoidance response in the shuttle-box test and the retention of the passive avoidance response in a step-through passive avoidance task were facilitated in aged rats by an acute treatment with DHEC. The effect on the acquisition and extinction of the pole-jumping performance after a single injection of DHEC at the beginning of the acquisition session was restricted to the first acquisition trial. A more potent effect on the acquisition of the shuttle-box response and on the retention of passive avoidance reaction was found in animals treated subchronically with DHEC. The latter animals also showed a facilitation of acquisition and an inhibition of extinction of the pole-jumping performance. In other experiments, the repeated administration of DHEC was followed by a decrease in the excessive grooming in aged rats, which is considered a sign of the lack of adaptability of these animals. A facilitation of the compensatory mechanisms in experimental models of vertigo has also been found in animals treated with DHEC.

Animals↗
PubMed1990

Effects of vinburnine on experimental models of learning and memory impairments.

Retrograde amnesia can be induced experimentally in mice by injecting them with scopolamine (3 mg/kg, IP) or by inducing seizures with pentylenetetrazol (50 mg/kg, IP), and in rats by subjecting them to hypobaric hypoxia (at a barometric pressure of 300 mmHg for 3 min). We have studied the effects of vinburnine (VNB) in these amnesic states compared to vincamine (VNC) and nicergoline (NCG), in order to assess its activity on drug-induced learning and memory impairments. Vinburnine reduced the disrupting effect of both scopolamine and pentylenetetrazol-induced seizures on the retention of a step-through passive avoidance behavior in mice and on the acquisition of shuttle-box active avoidance behavior in rats. This effect was dose-related up to 20 mg/kg, the peak effect dose after IP administration, and more pronounced than that of VNC and NCG in some tests. These results indicate that VNB influences learning and memory processes disrupted by a pharmacological manipulation. In particular, as scopolamine acts as anticholinergic drug, it is possible that VNB mechanism of action includes also a stimulation of acetylcholine neurotransmission.

Amnesia, Retrograde↗
PubMed1990

Acetylcarnitine reduces the immobility of rats in a despair test (constrained swim).

Male rats forced to swim in a cylinder adopted an immobile posture. Immobility was reduced by acetylcarnitine (5, 10, and 20 mg/kg) and by antidepressant drugs, such as desipramine and iproniazid, injected 24, 5, and, again, 1 h prior to behavioral testing. Acetylcarnitine also potentiated the anti-immobility effect of antidepressant drugs in the despair test. Chronic (10 days) treatment with acetylcarnitine mimicked the effect found after acute administration. It is possible that the action of the acetylcarnitine on the despair test is indicative of an antidepressant activity of this drug that is dependent on a change in the sensitivity of monoamine receptors in the brain.

Acetylcarnitine↗
PubMed1990

Memory deficits of aged male rats can be improved by pyrimidine nucleosides and n-acetyl-glutamine.

The pyrimidine nucleosides uridine (URI) and cytidine (CYT), alone or associated with n-acetyl-glutamine (NAG), were injected acutely or subchronically to aged (26 months old) male rats of the Sprague-Dawley strain. Learning and memory abilities of the animals were studied with tests of avoidance behavior. The acquisition of active avoidance behavior was studied with the shuttle-box test. A step-through type of passive avoidance task was used to examine the retention of passive avoidance responses. The acquisition of the active avoidance behavior and the retention of the passive avoidance response were reduced in aged animals as compared with those of young animals. Neither the acute treatment of old rats with URI and CYT alone nor that associated with NAG exerted any effect on the behavioral tests. In contrast, the subchronic treatment with URI and CYT was followed by a facilitation of acquisition of active avoidance behavior in the shuttle box and of retention of passive avoidance responses in the dark box. A more potent effect on the acquisition of the shuttle-box behavior and on the retention of passive avoidance reaction was found in animals treated subchronically with the pyrimidine nucleosides associated with NAG. These effects may be related to the role of pyrimidines in the synthesis of ribonucleic acid, which is indispensable for learning and memory processes.

Aging↗
PubMed1989

Effects of calcitonin on morphine tolerance and withdrawal syndrome in morphine physically dependent rats.

We investigated the effect of acute or chronic peripheral administration of [Asu1.7]eel-calcitonin on the development of tolerance to the analgesic effect of morphine and on the naloxone-precipitated withdrawal syndrome in morphine-dependent rats. Neither the analgesic effect of acute morphine nor the development of tolerance to the antinociceptive effect of this drug was modified by calcitonin. However, the chronic but not the acute administration of calcitonin attenuated some signs and symptoms of morphine withdrawal.

Animals↗
PubMed1989

Prolactin as a protective factor in stress-induced biological changes.

The adenohypophyseal hormone prolactin (PRL) is released during stress of physical and psychological nature. In animals, this hormone facilitates adaptive behavior, induces analgesia, and enhances grooming behavior. It also reduces corticosterone secretion and the incidence of gastric ulcers induced by physical stress. It is possible that PRL plays a protective role against stress-induced biological modifications in animals.

Animals↗
PubMed1988

Dihydroergocristine and memory alterations of aged male rats.

The ergot alkaloid derivative dihydroergocristine (DHECS) was injected acutely or subchronically to aged male rats of the Sprague-Dawley strain, 26 months old, at the dose of 0.05 or 0.1 mg/kg. Learning and memory ability of the animals were studied with tests of avoidance behavior. The acquisition of active avoidance behavior was studied with the shuttle-box and pole-jumping tasks. In the latter, the extinction of active avoidance behavior was also studied. A step-through type of passive avoidance task was used to examine the retention of passive avoidance responses. The acquisition of the active avoidance behavior and the retention of the passive avoidance response were reduced in aged animals as compared to those of young animals. Acute treatment of old rats with DHECS was followed by a facilitation of acquisition of active avoidance behavior in the shuttle box and of retention of passive avoidance responses in the dark box. The effect on the acquisition and extinction of pole-jumping behavior after a single injection of DHECS at the beginning of the acquisition session was restricted to the first acquisition trial. A more potent effect on the acquisition of the shuttle-box behavior and on the retention of passive avoidance reaction was found in animals treated subchronically with the ergot derivative (0.05 and 0.1 mg/kg for 10 days). These rats also showed a facilitation of acquisition and an inhibition of extinction of pole jumping behavior.

Aging↗
PubMed1988

Spatial learning potentiates the stimulation of phosphoinositide hydrolysis by excitatory amino acids in rat hippocampal slices.

Stimulation of phosphoinositide (PI) hydrolysis by excitatory amino acids (glutamate and ibotenate) or norepinephrine was potentiated in hippocampal slices from rats trained in an eight-arm radial maze, used as a test of spatial learning. No difference in basal or carbamylcholine-stimulated PI hydrolysis was found between control and trained animals. An increased PI response to excitatory amino acids and norepinephrine was not found in hippocampal slices prepared from animals trained in a shock conditioning avoidance test. These results suggest a possible involvement of specific glutamate receptors coupled with PI hydrolysis in the synaptic mechanisms underlying formation and/or storage of spatial memory.

Animals↗
PubMedDate not supplied

Behavioral changes induced by the thyrotropin-releasing hormone analogue, RGH 2202.

The behavioral activity of the thyrotropin-releasing hormone (TRH) analogue, L-6-ketopiperidine-2- carbonyl-leucyl-L-prolinamide (RGH 2202), has been studied in the rat. The number of errors in a radial maze test was reduced after acute intraperitoneal (IP) injection of RGH 2202 at the dose of 5 or 10 mg/kg. Grooming activity was increased with a lower dose, 1 mg/kg. Hypoxia-induced amnesia, as assessed with active and passive avoidance behavior tests, was reversed in rats treated with 5 or 10 mg/kg of the drug. The loss of learning and memory capacity shown by aged rats in the same behavioral tests was also reduced after injection of RGH 2202. In a test for sexual activity of male rats, the higher dose of the drug induced a facilitation of mounting and ejaculations, while smaller doses were ineffective. The rotorod test revealed a decreased number of falls in animals treated with 5 or 10 mg/kg of RGH 2202. In all behavioral tests, the same doses of natural thyrotropin-releasing hormone (TRH) were less effective, indicating that this analogue may be qualified as a potentially active drug in human pathologies.

Animals↗
PubMedDate not supplied

Protective action of phosphatidylserine on stress-induced behavioral and autonomic changes in aged rats.

Phosphatidylserine (PS) was administered in aged rats subjected to various stressor stimuli in order to evaluate its effect on grooming behavior, core temperature and gastric ulcers. Novelty-induced grooming appeared to be increased in aged rats as compared to young controls. The subchronic intraperitoneal treatment with PS (20 mg/kg/day for 20 days) decreased grooming activity in aged rats, whereas it did not affect that of young animals. Restraint stress induced hyperthermia in both aged and young rats. However, 90 min after the beginning of restraint, PS-treated old rats showed a normalization of core temperature. Furthermore, restraint-plus-cold stress induced gastric ulcers in both aged and young rats. The treatment with PS was followed by a decreased incidence of gastric lesions in aged, but not in young rats. The mechanism of PS protective action against stress-induced behavioral and autonomic changes is unknown, but it may involve the brain level as this drug exerts a noteworthy influence on behavior and autonomic functions.

Aging↗
PubMedDate not supplied

Effects of RGH 2202 on cognitive and motor behavior of the rat.

The behavioral activity of the thyrotropin-releasing hormone (TRH) analogue, L-6-ketopiperidine-2-carbonyl-leucyl-L-prolinamide (RGH 2202), has been studied in animal models of central neurotransmission disruption. In 24-month-old rats, repeated administration of the peptide (5 or 10 mg/kg/day, injected IP for 20 days) was followed by a facilitated acquisition of active avoidance behavior in the shuttle-box test and retention of passive avoidance reaction in a step-through passive avoidance task. Also, ambulation in an open field was increased and motor performance and co-ordination in the rotorod test was facilitated by the treatment. Scopolamine-induced amnesia was reverted by RGH 2202 in adult rats tested both in active and passive avoidance tasks. Cognitive deficits induced in rats by prenatal manipulation with methylazoxymethanol (MAM) were reduced in adulthood by repeated administration with RGH 2202. These results indicate that the TRH-analogue, RGH 2202 may improve cognitive and motor disturbances in aging or induced by central neurotransmission disruption. It is possible that the peptide is functioning, at least in part, by intervening with the central cholinergic neurotransmission.

Age Factors↗
PubMedDate not supplied

Dihydroergocryptine improves behavioral deficits of aged male rats.

Dihydroergocryptine (DHECP), an ergot alkaloid with potent dopaminergic activity, was injected acutely or subchronically to aged (24 months old) male rats of the F344 strain, at the dose of 0.05 or 0.1 mg/kg. The immobility in the "despair" test (constrained swim) was longer in 24-month-old rats than in younger animals. This behavioral change was reduced in rats treated subchronically with DHECP, but no significant change was found in animals with acute treatment. Aged rats showed an increased haloperidol-induced catalepsy and a reduced motor performance and coordination as compared to animals of 2 and 10 months of age. Acute treatment with DHECP was followed by an attenuation of haloperidol-induced catalepsy and an improvement of motor performance and coordination of aged rats. Similar results were obtained after subchronic treatment with DHECP, but the effect on the rotorod behavior was more potent after subchronic treatment than after acute injection of the drug. It is possible that the improvement of behavioral deficits of aged rats after the treatment with DHECP depends on the facilitating effect of this drug on central dopamine transmission that may be impaired in these animals.

Aging↗
PubMedDate not supplied

[In the absence of a bioethics debate. Comments on the Decision of the Constitutional Division of the Supreme Court of Justice of Costa Rica on the prohibition against in vitro fertilization].

The ruling by Costa Rica's Constitutional Court on the prohibition of in vitro fertilisation is a consequence of the negligible development of Bioethics, the lack of public debate on the issue and the absence of adequate regulation. Prohibition of such a vital medical technique represents an abuse of power by the courts, and thus curtails other fundamental rights, research, progress and bioethics' debate.

Bioethics↗
PubMedDate not supplied

The effects of acetyl-l-carnitine on experimental models of learning and memory deficits in the old rat.

Experimental models of learning and memory deficits in aged rats can be studied by means of behavioural tests that provide an important tool for evaluating the effect of drugs on these parameters. Active and passive avoidance tests showed a clear impairment of learning and memory capacity of old rats. These tests were also used to study the behavioural effect of acetyl-l-carnitine in aged rats. The subchronic treatment with this drug was followed by a significant improvement of acquisition and retention of avoidance responses, indicating a facilitation of learning and memory capacity of aged rats.

Acetylcarnitine↗
PubMedDate not supplied

Pyroglutamic acid improves learning and memory capacities in old rats.

The effects of the arginine salt of pyroglutamic acid (2-oxo-pyrrolidone carboxylic acid, PCA) on learning and memory capacities of old rats were studied in a subchronic treatment schedule (i.p. injection of 0.1 and 1 g/kg/day for 15 days). The acquisition and extinction of active avoidance behaviour were studied in a pole-jumping test situation. The retention of passive avoidance response was examined in a step-through passive avoidance task. PCA facilitated the rate of acquisition of pole-jumping response, and inhibited the extinction of the response. The dose of 1 g/kg was more potent than 0.1 g/kg in this respect. Also in the passive avoidance task, the treatment with PCA was followed by an improvement of avoidance retention. These results indicate that PCA is a behaviourally active compound in that it improves learning and memory capacities in old rat.

Aging↗