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G Calamandrei

Publications and source records attributed to G Calamandrei.

At least 37 records · Page 2Linked to original sources
PubMed1996

Systemic administration of anti-NGF antibodies to neonatal mice impairs 24-h retention of an inhibitory avoidance task while increasing ChAT immunoreactivity in the medial septum.

Neonatal mice received subcutaneous injections of either antibody against murine NGF raised in goat (3 mg, injection volume 50 microliters) or preimmune serum on postnatal days 2, 4, 6, 8, 10, and 12. They were tested on postnatal days 15-16 or 20-21 for learning and 24-h retention of a passive avoidance step-through task. Immunostaining for choline acetyltransferase (ChAT) was measured in two cholinergic forebrain areas (septum and caudate-putamen) on postnatal day 16 or 21. Locomotor activity and exploratory behavior in an open-field test were also assessed on day 17 or 22, following a single administration of either scopolamine (2 mg/kg) or saline solution. While anti-NGF treatment did not affect acquisition on day 15, impairment in retention was evident on day 16. On days 20-21, no effects were found either on acquisition or on retention capabilities. Analysis of ChAT immunostaining revealed a significant increase of ChAT-immunopositive cells in the medial septal area in 16-day-old but not in 21-day-old mice. Behavior in the open-field test and age-typical response to scopolamine were not altered by anti-NGF at either of the two ages considered. These data support the view that immunological neutralization of endogenous NGF specifically affects the maturation of retention capabilities in altricial rodents, and confirm the involvement of forebrain cholinergic mechanisms in early memory processes.

Aging↗
PubMed1996

Nerve growth factor affects passive avoidance learning and retention in developing mice.

The present studies investigate the effects of early nerve growth factor (NGF) administration on the ontogenetic profile of learning and retention capacities in mice. The learning paradigm used required the animals to withhold an escape response from a vibrating platform to avoid a punishment (step-down passive avoidance). In Experiment 1, acquisition of step-down passive avoidance was essentially the same in 11- and 15-day-old mice whereas only the latter showed significant retention after 24 h. In younger animals, data pointed to a facilitating effect of familiarization with the test environment. In Experiment 2 ICV NGF treatment on postnatal day 9 increased step-down latencies in both reinforced and nonreinforced pups on day 11. Moreover, NGF mice exposed in nonreinforcement condition on day 11 failed to acquire the avoidance response 24 h later, suggesting that the treatment anticipated the appearance of latent inhibition. Results of Experiment 3, investigating the effects of different durations of preexposure to the test apparatus on passive avoidance acquisition 24 h later, supported the specificity of NGF effects on the emergence of latent inhibition. These findings suggest that neural populations responsive to NGF trophic effect are involved in the maturation of early learning and retention capacities in rodents.

Animals↗
PubMed1995

Neuronal growth factors, neurotrophins and memory deficiency.

CNS and PNS ontogenesis are regulated by various proteic factors, and the best characterized of which still remains Nerve Growth Factor (NGF), a molecule exerting trophic, tropic (i.e. directing growing axons toward NGF-releasing target tissue) and differentiative effects on a number of neural and non-neural (e.g. mast-cells) cell lines. Other Growth Factors (GFs), called 'neurotrophins' (BDNF, NT-3, NT-4, NT-5) also exert similar effects on specific neural cell population. Other GFs (EGF, TGFs, IGFs, FGFs) share these growth-promoting properties with the neurotrophins. NGF appears to regulate specifically the postnatal maturation of the CNS cholinergics in altricial rodents. In adults, cholinergic neurons show retrograde transport for NGF and degeneration of cholinergic neurons after fimbria-fornix transection is prevented by NGF infusion, suggesting a role for NGF in maintaining normal cholinergic function in adulthood. However, peptidergic neurons (e.g. SP-positive cells) seem also to be influenced by perinatal NGF administration, indicating that the spectrum of NGF actions is wider than previously reported. In recent years we investigated the role of NGF in controlling behavioural maturation in the early postnatal period by comparing NGF effects with those of related and non-related neurotrophins (EGF, basic FGF, IGF-1, Transforming GF-alfa). We found that a single intracerebral injection of NGF accelerates cholinergic maturation on postnatal day (PND) 20, as shown by the enhanced reactivity to the muscarinic blocker scopolamine. Scopolamine-induced hyperactivity, normally appearing at the end of the third week, emerges already at PND 5 following NGF administration on PND 2 and 4.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Impairment of passive avoidance learning following repeated administrations of antibodies against nerve growth factor in neonatal mice.

CD-1 Swiss mice were used to study the effects of repeated intracerebroventricular (i.c.v.) injections, on postnatal days (PND) 3, 6, 9, of rabbit antiserum (50 micrograms) raised against murine nerve growth factor (NGF) both on locomotor activity in an open field test (PND 10) and on a passive avoidance learning test (PND 11 and 12). While no difference was evident in locomotor activity levels between anti-NGF and control pups, an impairment of anti-NGF pups was detectable in the passive avoidance performance. Removal of endogenous NGF seems to produce a detrimental effect on a behavioural performance which is known to be under central cholinergic control, confirming previous reports on the role of NGF in early neurobehavioural responding in altricial rodents.

Acetylcholine↗
PubMed1994

Age-dependent effects of NGF and scopolamine on suckling behavior of neonatal mice.

Nerve growth factor (NGF) influences the neurochemical differentiation of central cholinergic neurons of developing rodents. In this study, NGF was given intracerebrally to mice on different postnatal days (days 5 and 7, or days 8 and 10). Pups were tested for suckling behavior 24 h after the second NGF injection, following systemic administration of either the muscarinic cholinergic antagonist scopolamine or saline solution. Scopolamine significantly impaired nipple attachment on day 11 but not on day 8, and decreased locomotor activity in 11-day pups. NGF given on days 5 and 7 increased paddling and treading on day 8, and this effect was more pronounced in scopolamine injected pups. Pretreatment with NGF on days 8 and 10 decreased activity levels in 11-day pups. The differences in the effects of scopolamine at successive ages suggest that distinct portions of the cholinergic system mature at different rates and that sensitivity to NGF is age dependent. NGF appears to influence functional maturation of that portion of the cholinergic system involved in the regulation of locomotor activity.

Aging↗
PubMed1994

IGF-I and IGF-I24-41 but not IGF-I57-70 affect somatic and neurobehavioral development of newborn male mice.

Insulin-like growth factor (IGF-I) is a trophic factor for both neurons and glial cells. Its presence in developing and adult nervous system suggests an important role for this peptide in the development of neural circuitries. Neonatal male mice of the CD-1 outbred strain were injected intracerebroventricularly with either recombinant IGF-I, synthetic IGF-I fragment 24-41 or IGF-I fragment 57-70 on postnatal days (PND) 2, 4, and 7. Physical traits such as body weight gain, body length, and tail length were recorded daily from PND2 to PND13. Sensorimotor development was scored according to a modified Fox's scale. The ultrasonic vocalization pattern on PND8 and homing performance on PND10 were also recorded. Measures for body weight gain and tail length of the pups were significantly increased following treatment with the whole IGF-I peptide. However, neither IGF-I nor the smaller fragments affected mice sensorimotor development. IGF-I and IGF-I24-41 but not IGF-I57-70 increased the rate of ultrasonic calls of the pups measured on PND8. These data provide evidence that IGF-I regulates somatic growth and behavioral development when administered in newborn mice and that different portions of the peptide can exert different effects.

Animals↗
PubMed1994

Prenatal oxazepam affects passive avoidance performance of preweaning mice.

CD-1 outbred mice were exposed to oxazepam on fetal days 12-16 by maternal administration (per os of 15 mg/kg twice daily at 8 a.m. and 8 p.m.) and fostered at birth to untreated dams, while control mice received vehicle solution. Mice were then tested on postnatal day 14 and 15 in a passive avoidance apparatus for their ability to withhold a step-down response from a vibrating platform. The step-down response was punished with a mild footshock. Each animal was subjected to a maximum of 15 trials. Mice prenatally treated with oxazepam showed an impairment in the acquisition of the task as indicated by shorter latencies to step-down throughout the 15 trials in both sessions (days 14 and 15). As control nonreinforced animals prenatally treated with oxazepam did not show a similar alteration in latency to step-down, these data suggest that prenatal exposure to oxazepam influences behavioral performance of preweaning mice in an aversively motivated task.

Animals↗
PubMed1994

Differential expression of Fos protein in the brain of female mice dependent on pup sensory cues and maternal experience.

Immunoreactivity for Fos protein following 30 min of sensory and behavioral experience with foster pups was measured in different brain areas of nulliparous female Balb/c mice who were intact, ovariectomized, or selectively depleted of olfactory bulb noradrenaline. Fos expression was also investigated in intact nulliparous female mice undergoing distal exposure to pup sensory cues. Behavioral interaction with pups increased Fos immunoreactivity in the olfactory areas (anterior olfactory nucleus, piriform cortex, corticomedial amygdala, and entorhinal cortex) as well as in the medial preoptic area, and this occurred regardless of whether females were intact or ovariectomized. Noradrenaline depletion of the olfactory bulb prevented Fos induction in primary olfactory areas, but not in the medial preoptic area, whereas distal exposure to pup cues enhanced Fos expression in the olfactory areas but not in the medial preoptic area.

Amygdala↗
PubMed1993

Growth factors in behavioral teratology.

Polypeptide Growth Factors are protein molecules which regulate cell proliferation and/or differentiation. A number of different Growth Factors (GFs) have been identified and characterized in recent years, and they have been shown to control several physiological processes, such as growth, repair, differentiation, and development of specific cell populations. In particular Nerve Growth Factor, the best characterized among the about 30 GF molecules, is endowed with specific activities on cholinergic and peptidergic CNS neurons. Several GFs originally named according to their biological activity (Epidermal Growth Factor, EGF; Fibroblast Growth Factor: FGF; Transforming Growth Factor: TGF; Insulin-like Growth Factor: IGF) have been recently found in the central nervous system. The effects of in vivo GF administration on the ontogenesis of altricial rodents are reported. Indexes of neurobehavioral maturation are accelerated upon neonatal NGF and bFGF exposure, while a similar treatment with EGF exerts both growth-promoting and growth-inhibiting effects on mouse somatic and behavioral development. Administration of IGF appears to affect ultrasonic vocalization in mouse pups. Moreover, NGF given intracerebroventricularly to newborn mice anticipates both the appearance of the scopolamine-induced hyperactivity and the maturation of behaviours under cholinergic control. The present findings are in agreement with a model where different GFs can "switch on" developmental events leading sometimes to dramatic changes in the normal ontogenetic pattern.

Age Factors↗
PubMed1992

Olfactory recognition of infants in laboratory mice: role of noradrenergic mechanisms.

Noradrenaline depletion of the olfactory bulbs induces cannibalism at parturition in primiparous mice, without producing anosmia or impairment of maternal behaviour. Similar lesions made in multiparous experienced females do not result in cannibalism. The present studies investigated 1) whether a 30-min exposure to pups or to distal cues from pups given to virgin females before noradrenaline depletion of the olfactory bulbs overcame the impairment in recognition at first parturition, and 2) whether noradrenaline-depleted females allowed to care for their pups for the 24 h following parturition showed a failure in recognition on a second parturition. Experiment 1 showed that exposure to distal cues from pups enabled the females to successfully recognize pups at parturition in comparison to naive females. However, neither the exposure to pup cues nor the fully interactive experience with pups overcame the disruptive effect on recognition at birth of the noradrenaline depletion. In Experiment 2, we found that olfactory recognition was impaired in noradrenaline-depleted females on second parturition, in spite of the mothering experience with their own pups.

Animals↗
PubMed1991

NGF and cholinergic control of behavior: anticipation and enhancement of scopolamine effects in neonatal mice.

Male mouse pups of the Swiss-CD1 strain received on postnatal days 2 and 4 either an intracerebroventricular (i.c.v.) administration of 30 micrograms murine nerve growth factor (NGF) or cytochrome c. Pups were then tested for suckling behavior on their anesthetized multiparous dam on day 5, following intraperitoneal (i.p.) administration of either the muscarinic cholinergic antagonist scopolamine (2 mg/kg) or saline solution (0.9%). Scopolamine produced a significant increase in latency time to suckle, while reducing the time pups spent attached to the nipple. NGF exposure enhanced scopolamine effects on latency to suckle as well as on time spent attached to the nipple. More striking, NGF pups showed a marked hyperactivity after scopolamine, an effect which normally appears only around weaning time. These results support the hypothesis that NGF plays a crucial role in the functional maturation of central cholinergic mechanisms involved in the control of behavior.

Animals↗
PubMed1990

On the functional role of polypeptide growth factors in rodent neurobehavioral development.

A number of polypeptide growth factor molecules have been discovered and characterized in the recent years. Most of them appear to play important roles in the ontogeny of both vertebrates and invertebrates, and some growth factors are specifically involved in brain development of altricial mammals such as rats and mice. In particular, Nerve Growth Factor (NGF) seems to be involved in degenerative processes of the aged CNS and to control brain development, particularly cholinergic systems. Data concerning NGF effects on neurobehavioral development of neonatal mice are reported, and compared with the specific alterations caused by neonatal Epidermal Growth Factor (EGF) exposure on a number of physical and behavioral scores. While NGF mainly anticipated behavioral development, EGF exerted both growth-promoting and growth-inhibiting effects.

Aging↗
PubMed1990

Polypeptide growth factors in mammalian development: some issues for neurotoxicology and behavioral teratology.

Protein molecules known as Growth Factors (GFs) appear to play an important regulatory role in a number of CNS functions. In particular Nerve Growth Factor (NGF), the best characterized among about 30 GF molecules, is endowed with specific activities on cholinergic and peptidergic CNS neurons. Indexes of neurobehavioral maturation are accelerated in the mouse by neonatal NGF exposure, while a similar treatment with EGF exerts both growth-promoting and growth-inhibiting effects on somatic and behavioral development. Scopolamine hyperactivity is enhanced around weaning by NGF pretreatment. Data are discussed along with (a) NGF prevention of cholinergic system damage and (b) the molecular mechanism of endogenously-triggered CNS repair processes.

Animals↗
PubMed1989

Epidermal growth factor has both growth-promoting and growth-inhibiting effects on physical and neurobehavioral development of neonatal mice.

The protein molecule epidermal growth factor (EGF) exerts powerful effects on mouse physical development, since repeated subcutaneous administrations of murine EGF (3.5 mg/kg, from postnatal day 2 to postnatal day 10) cause precocious eyelid opening (as early as day 8 instead of day 13 in control littermates receiving 3.5 mg/kg cytochrome c) and precocious eruption of the lower incisors (day 6 instead of day 8). By contrast, the same EGF treatment retards both the rate of body growth and the full appearance of several neurobehavioral signs of maturation, such as righting and grasping responses. Neonatal mice receiving 5 mg/kg murine nerve growth factor (NGF) under the same treatment schedule, although showing a significant retardation in body weight gain, exhibited only limited changes in neurobehavioral maturation. Specifically, the appearance of slow and swift righting, response to strong tactile stimulation, hindlimb and forelimb grasping, pole grasping, and vertical screen and screen climbing were significantly retarded by EGF and slightly advanced by NGF (the only significant NGF effect was an acceleration of swift righting maturation). Polypeptide growth factors seem to play an important role in physical and neurobehavioral development of altricial rodents, orchestrating the relative maturation of different tissutal targets on different developmental stages.

Aging↗
PubMed1986

Odor-aversion learning and retention span in neonatal mouse pups.

One hundred and sixty-four litters of Swiss CD-1 random-bred mice were used to assess learning and retention capacities during the first postnatal week. In Experiment 1, whole 7-day litters were exposed for 65 min to commercial extracts of either mint or lemon sprinkled over wood shavings. Five minutes after the beginning of the exposure, half of the litters were injected ip with the illness-inducing agent lithium chloride (LiCl; 0.20 M, 2% of body weight); the other half was treated with saline solution (8% NaCl). On Postnatal Day 10, the animals were singly introduced in a warmed arena for a 180-s preference test, and the time spent in the mint- and lemon-scented areas of the apparatus was recorded. When compared with saline-injected pups, mice that experienced lemon-LiCl pairings showed a significant aversion for the lemon-scented area, while the mint aversion in the mint-LiCl group just missed statistical significance. Three additional control groups (unhandled on Day 7, or only LiCl- or saline-injected) did not show significant preferences for either the mint or the lemon odor. In Experiment 2, litters of 3, 5, or 7 days were similarly exposed to lemon-scented shavings for either 5 or 20 min, injected with LiCl or saline, and then exposed for an additional 60 min to the shavings. On Postnatal Day 10, tests like those of Experiment 1 showed a significant odor-aversion in animals conditioned on Day 7, but not in those conditioned on Day 3 or 5. In Experiment 3, 3- and 5-day old pups were exposed to lemon odor-LiCl or -NaCl pairings, and tested for aversion after 3 or 7 days (CS duration 5 min before injection and either 30 or 60 min after injection). Only when the conditioning-testing interval was limited to 3 days did LiCl-injected groups show a significant aversion, which did not depend on duration of CS exposure.

Animals↗
PubMed1978

[Corrective methods of the aphaque eye (author's transl)].

While in most cases, the operation for cataract gives full satisfaction to the patient, it is nevertheless a fact that in some cases--perhaps only a few but certainly not to be neglected--the long term effects of such an operation are not well tolerated. The cause is not faculty performance of the operation, but most often unsuitable operational timing or technics or else defective or illchosen visual aids. These, therefore are the problems dealt with in this paper by the authors who made thorough study of the aphaque eye and its corrective methods.

Aphakia, Postcataract↗