Biomedical subjects

R DeLucia

Publications and source records attributed to R DeLucia.

10 recordsLinked to original sources

PubMed1991

Effect of fencamfamine on avoidance performances of rats.

The effects of fencamfamine (1.0 and 5.0 mg/kg, ip, single dose) on an inhibitory task were studied in rats (N = 15 per group). Post-training treatment with fencamfamine (1.0 mg/kg) significantly increased avoidance latency from 23 +/- 3 to 146 +/- 28 and 170 +/- 33 s for training day 1 and day 7, respectively, indicating an enhancement of retention. However, retention was significantly reduced with a high dose of fencamfamine (5.0 mg/kg). These results demonstrate that fencamfamine caused a reproducible dose-related increase and reduction in avoidance latency.

Animals↗

PubMed1991

Hyperprolactinemia induced by long-term domperidone treatment does not alter the sensitivity of striatal dopamine receptors.

We investigated the effect of hyperprolactinemia induced by long-term domperidone treatment (10.0 mg/kg, single daily dose, ip) on striatal dopamine (DA) receptor sensitivity in male Wistar rats weighing 250-300 g (N = 8). Domperidone treatment for 7 days continued to produce an increase in serum concentration of prolactin (PRL) from 17.3 +/- 2.2 to 33.1 +/- 7.3 and from 16.8 +/- 2.3 to 21.9 +/- 2.1, 2 and 72 h after domperidone withdrawal, respectively. Hyperprolactinemia induced by long-term domperidone treatment did not change binding sites (Bmax) and dissociation constant (Kd) of [3H]-spiroperidol binding when compared to controls. These results show that hyperprolactinemia induced by long-term domperidone treatment does not effect the sensitivity of striatal DA receptors presumably because the effect of neuroleptic drugs is due to their interaction with the receptors and not to the concomitant hyperprolactinemia.

Animals↗

PubMed1990

Carnosine-, calcitonin gene-related peptide- and tyrosine hydroxylase-immunoreactivity in the mouse olfactory bulb following peripheral denervation.

We report the effects of olfactory peripheral deafferentation by intranasal irrigation with ZnSO4 on carnosine and CGRP immunoreactivities in the mouse olfactory system. In the normal rodent olfactory epithelium carnosine immunoreactivity is associated with the olfactory receptor neurons. Conversely, CGRP immunoreactivity appears to be associated with the trigeminal innervation of the nasal cavity. Following lesion the magnitude of carnosine immunoreactivity in the olfactory epithelium is strongly reduced while CGRP immunoreactivity is unaffected. In the olfactory bulb, deafferentation causes a strong reduction of carnosine immunoreactivity in the glomerular layer and, concurrently, of TH immunoreactivity in the juxtaglomerular neurons. CGRP immunoreactive fibers in the olfactory bulb are abundant in the glomerular layer both before and after deafferentation. These data demonstrate that, in the adult mouse, the immunocytochemically detectable levels of CGRP are not altered following lesion and indicate CGRP is not released directly from the olfactory neurons to induce TH production.

Animals↗

PubMed1990

Fencamfamine.

1. Studies on the mechanisms of FCF action using behavioural and biochemical methods have shown that all stimulant effects produced by acute administration of FCF are thought to be due to indirect activation of DA systems in CNS. 2. Changes in the sensitivity of pre- or postsynaptic DA receptors might underlie both tolerance and sensitization to the effects induced by long-term FCF administration.

Animals↗

PubMed1989

Behavioral and neurochemical effects of fencamfamine on rats: a chronobiologic approach.

Fencamfamine (FCF) is a psychostimulant classified as an indirect dopaminergic agonist. Circadian rhythms of some behavioral and neurochemical parameters were investigated in control rats and in rats which had been treated with a single dose of FCF across the 24-hr span. Rats were entrained to light/dark (LD) 12:12, lights on from 0700 to 1900. In behavioral experiments (performed in March) the rats were injected intraperitoneally with saline or FCF (3.5 mg/kg) at one of six times: 0900, 1300, 1700, 2100, 0100 or 0500. Fifteen minutes after treatment the duration of sniffing, rearing and locomotion was recorded during 120 min. Controls showed circadian rhythms for sniffing and rearing with acrophases at 2255 and 0118, respectively. In animals treated with FCF, only locomotion displayed significant circadian variation with acrophase at 1912. Two-way analysis of variance (ANOVA) showed a statistically significant circadian time-dependent effect of FCF on all behavioral parameters studied; the increase of sniffing, rearing and locomotion induced by FCF was higher in rats treated during the rest phase. In the biochemical studies (performed between March-June), rats were treated (i.p.) with saline or FCF (10 mg/kg) at one of four times: 0900, 1700, 2100 or 0100. The levels of homovanillic acid (HVA) in the striatum and tuberculum olfactorium, 5-hydroxyindolacetic acid (5-HIAA) in the cerebellum and 3-methoxy-4-hydroxypheniglycol (MHPG) in the frontal cortex were determined. Controls showed circadian rhythms for HVA (striatum), MHPG (frontal cortex) and 5-HIAA (cerebellum) with acrophases at 2233, 1955 and 1029, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1989

On the mechanism which mediates the effects of long-term administration of fencamfamine in rats.

This study analyzes the changes in the sensitivity of striatal dopaminergic (DA) receptors to apomorphine following withdrawal from long-term treatment with fencamfamine (10 mg/kg, for 40 days). Fencamfamine treatment decreased (34.8 +/- 3.2 vs 25.8 +/- 2.8, P less than 0.05) the stereotyped behavior induced by apomorphine (2.0 mg/kg, sc), but potentiated the effect of apomorphine (0.02 mg/kg, sc) in reducing the striatal levels of homovanillic acid (HVA) (0.41 +/- 0.02 micrograms/g vs 0.31 +/- 0.03 micrograms/g, P less than 0.01) and dihydroxyphenylacetic acid (DOPAC) (0.45 +/- 0.04 micrograms/g vs 0.34 +/- 0.03 micrograms/g, P less than 0.01). These results suggest that changes in pre- or postsynaptic DA receptors may underlie the tolerance and sensitization to the effects of fencamfamine.

Animals↗

PubMed1989

Striatal dopamine receptor supersensitivity after long-term haloperidol treatment of hypophysectomized rats.

Dopamine (DA) receptor sensitivity was studied after long-term treatment with haloperidol (0.5 and 3.0 mg/kg, ip, single daily dose) or saline in hypophysectomized and intact rats. Haloperidol treatment for seven days produced a 25 to 125% increase in [3H]-spiroperidol binding to striatal DA receptors in a dose-dependent fashion. The increase in binding sites (Bmax) was similar in both hypophysectomized and intact rats when compared to controls. The present results show that hypophysectomy does not effect the supersensitivity of striatal DA receptors induced by long-term haloperidol treatment.

Animals↗

PubMed1988

Psychostimulant effects of fencamfamine in healthy volunteers.

The effects of fencamfamine (25 and 50 mg po) were studied on acute psychophysiological and psychomotor performance in six healthy male volunteers. Stimulant effects, such as greater increases of critical flicker-fusion threshold, heart rate, blood pressure and stimulation assessed by self-rating, were more pronounced with the higher dose of fencamfamine. Paradoxical sedative effects were obtained with the 25 mg dose. Fencamfamine should not be considered only as an energizing agent, but also as an agent having a psychostimulant profile of effects.

Administration, Oral↗

PubMed1987

The effects of chronic treatment with fencamfamine on body weight, food intake and stereotyped behaviour in rats.

The effects of chronic treatment with fencamfamine (10.0 mg/kg, i.p.) or saline were studied in rats. Chronic fencamfamine treatment reduced body weight of rats below their normal body weight. Thereafter, weight increased, in parallel to that of control rats. There was an increasing trend in food intake in both groups and a reduction was observed in food intake on the first seven days of fencamfamine-treated rats. Fencamfamine repeated administration enhanced stereotyped sniffing while rearing behaviour gradually declined until 25 days. However, the same treatment did not interfere with the intensity of stereotypy. These findings suggest the need for a re-evaluation of current concept in the tolerance to the effects of fencamfamine and other stimulant drugs.

Animals↗

PubMed1987

Reduction of food intake by fencamfamine in rats.

Fencamfamine (1.0-10.0 mg/kg, i.p. single dose) reduced the food intake in a dose-effect relationship. The dose needed for the 50% inhibition of food intake (ID50) was 7.3 mg/kg. Fencamfamine-induced anorexia in rats (5.0 and 10.0 mg/kg) was followed by hyperactivity, stereotypy or both. Pretreatment with haloperidol antagonized the anoretic effect induced by fencamfamine. These findings suggest that the activation of central dopaminergic systems involved in feeding regulation may be responsible for the anoretic effect of fencamfamine and that this effect is associated with other central stimulant effects.

Animals↗