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M Ferdico

Publications and source records attributed to M Ferdico.

7 recordsLinked to original sources
PubMed1993

Influence of ventral tegmental area (A10 region) on flight behaviour elicited by hypothalamic stimulation in the cat.

The influence of the ventral tegmental area (VTA) (dopaminergic A10 group neurons) on flight behaviour, induced by hypothalamic stimulation, was studied in the cat. Co-stimulation of hypothalamus and VTA (ipsi- or contralateral) induced an increase of the flight latency. Slow-motion analysis of flight behaviour showed that this increase was due to the augmentation of the fixation latency (FL) whereas the upright latency (UL) was not modified. Sulpiride injection (50 mg/kg i.p.) provoked the disappearance of VTA effect without affecting the basal behavioural sequence. The results show that DA A10 group neurons increase the attentive component of the flight reaction, suggesting a possible influence of the DA A10 system on the mechanisms modulating focused attention in the animal.

Anesthesia↗
PubMed1989

Circling behavior: ethological analysis and functional considerations.

Head-turning and circling movements evoked by substantia nigra (pars compacta) (SNpc) stimulation have been ethologically analyzed in order to attribute a functional meaning to these lateralization processes. It has been shown that these motor acts, separated by a constant interval, may be considered a fixed action pattern. The duration of the single acts depends on the SNpc stimulation parameters: the increase in the stimulus strength produces an increase in the number of turns but does not induce the disappearance of the orientation movement. The body movement is always preceded by the head-movement. Haloperidol administration induces a dose-related increase of the orientation component of the motor pattern. These data together with others in the literature suggest the participation of the SNpc in the mechanism of shift in the focus of attention from one point to another in the contralateral surrounding environment.

Animals↗
PubMed1989

The influence of dopaminergic A10 neurons on the motor pattern evoked by substantia nigra (pars compacta) stimulation.

The influence of the mesolimbic-mesocortical dopaminergic (DA) system on the motor pattern evoked by substantia nigra pars compacta (SNpc) stimulation was studied. Electrical stimulation of the A10 group of neurons caused an inhibitory effect preferentially directed towards the orientation movement. Sulpiride administration at low dosages (50 mg/kg i.p.) did not modify this movement at the basal condition, but abolished the increase of its duration induced by ventral tegmental area (VTA) co-stimulation. Mesolimbic activation opposes the effects of SNpc stimulation, restraining the animal in its antero-posterior axis by means of orientation movement inhibition. The results suggest a role of the DA mesolimbic-mesocortical system in the maintenance of focused attention.

Animals↗
PubMed1988

Facilitatory effect of ventral tegmental area A10 region on the attack behaviour in the cat: possible dopaminergic role in selective attention.

Lateral hypothalamus (LH) stimulation in cats which do not spontaneously attack rats, produces an attack pattern which may be divided into 3 main stages: the first, defined as exploratory time (ET), begins with an environmental search and culminates in orienting towards the prey; in the second, defined as attack time (AT), the cat stalks the rat; the last is the biting stage in which the cat seizes and kills the prey by biting its head and neck. The effects of ventral tegmental area (VTA) stimulation on the latency of the whole sequence and on the different stages of the attack pattern were studied. VTA activation resulted in a significant decrease of biting latency, due to the reduction of exploratory time. Moreover, a significant period of prey fixation, seldom present during LH stimulation alone, was observed after VTA-LH co-stimulation. Sulpiride injection caused the disappearance of VTA effects on the predatory pattern. The results indicate that VTA activation induces a decrease in behaviour related to exploration of the environment, and an increase in the focusing of attention on the prey, which seems an important component in the regulation of the predatory pattern. Pharmacological evidence indicates that the VTA effect is mediated by the mesolimbic-mesocortical dopaminergic (DA) system.

Animals↗
PubMed1987

Inhibitory effect of the ventral tegmental A10 region on the hypothalamic defence reaction: evidence for a possible dopaminergic mediation.

The influence of A10 region neurons of the ventral tegmental area (VTA) on the defence reaction evoked by stimulation of the ventromedial hypothalamic nucleus (VMH) was studied in the cat. The latency of the hissing in the defence reaction increased when the VTA was stimulated both ipsi- and contralaterally. A sulpiride (50mg/kg i.p.) injection totally abolished the VTA-provoked increase of the hissing latency without affecting the basal response.

Animals↗
PubMedDate not supplied

Indications for caesarean section: results of a local study.

Records from 6820 deliveries of three year (1980, 1985 and 1988) were reviewed in order to collect informations on cesarean section trend and its indications in a public hospital of Milan, Italy. Data show the magnitude of the phenomenon in the wards considered and an evident increase of cesarean section proportion from 1980 (18.6%) to 1988 (26.9%). The frequencies of major indications has not changed much apart from dystocia which has decreased and previous cesarean section which has increased. A logistic regression model was performed to evaluate cesarean section risk factors. Distribution of cesarean section during the days of the week show higher (about 30%) cesarean section proportion Monday through Thursday compared with low proportion (20% or less) on Fridays and weekend-days; this suggesting a possible high proportion of pre-programmed cesarean section.

Adult↗