Maria Chiara Cassone

Priming effects of substance P on calcium changes evoked by interleukin-8 in human neutrophils

The neurokinin (NK) substance P (SP), which is a mediator of neurogenic inflammation, has been reported to prime human polymorphonuclear neutrophils (PMNs). The priming effects of SP on PMNs activated by recombinant interleukin‐8 (rIL‐8) were investigated. SP enhanced, in a dose‐ and time‐dependent way, the rise in cytosolic free‐calcium concentration, [Ca2+]i, evoked by the chemokine. The priming effects of SP were abolished by exposing PMNs to a calcium‐free medium supplemented with EGTA. The C‐terminal peptides SP(4–11) and SP(6–11) but not the N‐terminal peptide SP(1–7) shared the priming effects of SP. The selective NK‐1 receptor agonist [Sar‐9, Met(O)2‐11]SP mimicked the effects of SP, which were not reproduced by the selective NK‐2 receptor agonist [βAla‐8]‐NKA(4–10) or the selective NK‐3 agonist senktide. Two selective NK‐1 antagonists, CP96,345 and L703,606, dose dependently inhibited SP priming effects. These results demonstrated that SP primes PMNs exposed to rIL‐8 and suggested that SP priming effects are receptor mediated.

Rat brain metabolism enzyme activity variations following He−Ne laser irradiation

In order to gain insight into the metabolic modifications induced in rat brain tissues by helium-neon (He-Ne) laser irradiation, in the research described here, we investigated the variations in the activity of the enzymes aspartate transferase (AST, EC 2.6.1.4), both cytosolic and mitochondrial, glutamate dehydrogenase (GIDH, EC 1.4.1.3), and total superoxide dismutase (SOD, EC 1.15.1.1), in the brain of rats treated with a very small dose (1.08 J) of He-Ne laser radiation. The rats were sacrificed 4 h after the treatment. The enzymes were evaluated spectrophotometrically in brain extracts of irradiated animals and also in untreated rats (controls) and rats that underwent simulated treatment (stressed). The data obtained from 5-10 animals assayed individually showed that, in the in toto brain tissues of the irradiated rats compared to the stressed rats, there was a marked increase of total SOD, together with an appreciable decrease of cytosolic AST, and insignificant variations in mitochondrial AST and GIDH. Stress alone caused a considerable decrease of total SOD and small but statistically significant increases of s-AST, m-AST, and GIDH.

Action of a chronic arecoline administration on mouse motility and on acetylcholine concentrations in the CNS.

Abstract— The modifications of mouse motility and of the levels of acetylcholine (ACh) in two sections of the CNS caused by a chronic administration of 4.5; 9.5; 28.5 and 60 mg kg‐−1 day−1 of arecoline for 20 days have been studied. At low doses (4.5 and 9.5 mg kg−1 day−1), arecoline caused no modification of the ACh levels and of the motility. The higher doses (28.5 and 60 mg kg−1 day−1) caused a reduction of the mouse motility and an increase of the ACh levels in the subcortical structures of the CNS of the mouse.

Action of thyroid hormones, diazepam, caffeine and amitriptyline on memory decay (“forgetting”)

Abstract A straircase maze has been used to test the modifications induced by a chronic administration of caffeine, amitriptyline, diazepam and hypo or hyperthyroidism in the decay of the rat performance (“forgetting”) caused by the interruption of the daily training. Diazepam 0.35 mg/kg and 0.07 mg/kg, caffeine 21 mg/kg, amitriptyline 1 mg/kg, increased the forgetting. Hyperthyroidism caused no modifications of behaviour; high hypothyroidism increased and low hypothyroidism completely abolished the decay of rat performance consequent to the daily training interruption.

Action of 5-hydroxytryptamine, histamine and methergoline on phagocytosis.

Polymorphonuclear leukocytes of guinea pig were used to study the action of 5-hydroxytryptamine, histamine and methergoline on phagocytosis. Phagocytosis was reduced by 5-HT; this effect was only in p

Effect of in vivo HeNe laser irradiation on biogenic amine levels in rat brain

In order to elucidate the metabolic modifications induced in rat brain by low power He-Ne laser irradiation in vivo, the variations in the biogenic amine levels in cortex, striatum and hippocampus were studied. Noradrenaline (NA), dopamine (DA) and serotonin (5-HT) were evaluated by HPLC-EC on irradiated rats, untreated rats (controls) and rats which had undergone restraint stress (stressed). The results obtained on groups of four to eight rats assayed individually showed that irradiation caused a strong increase in 5-HT in striatum and hippocampus, a small but significant decrease in NA in cortex, and DA levels were not significantly affected. Restraint stress per se led to a considerable decrease in 5-HT and DA in striatum and hippocampus, but did not significantly alter the NA levels.

Effects of combinations of arecoline and atropine on mouse motor activity.

1. Effects on motor activity were studied after acute administration of arecoline, atropine alone and in combination in the mouse. 2. Atropine from 15 to 45 mg/kg increased motor activity. 3. A reduction in activity was observed at doses of arecoline above 0.2 mg/kg. 4. An antagonism between arecoline and atropine was observed only at low doses of arecoline, while higher doses of arecoline in association with atropine increased activity.

Behavioral interferences modify the acceleration in memory decay caused by diazepam

A staircase maze has been used to test the modification induced by a chronic administration of different doses of diazepam in the decay of the rat performance caused by an interruption of 20 days in the daily training. The possibility that behavioral interferences modify the diazepam effect has been examined by testing the rat in an open field or in a Y maze during the interruption of the training in the staircase maze. The diazepam effect on the rat behavior in the staircase maze increased linearly with the doses; an intercalated training in the open field increased the diazepam effect, while an intercalated training in a Y maze completely abolished the increase of forgetting caused by diazepam.

Studies on the in vitro inversion of flurbiprofen

This paper reports in vitro studies on the metabolic inversion of flurbiprofen (FL), an arylpropionic acid antiinflammatory agent (2-APA). The inversion was studied with both rac-FL and R-FL, by incubation with rat hepatic microsomes, in the presence of either CoASH and ATP or NADPH. The two isomers of the drug were separated as their (+)-(R)-1-phenylethylamides by direct phase high-performance liquid chromatography on a silica gel column with an achiral mobile phase. The inversion was more pronounced in the presence of CoASH and ATP for both the racemate and the R-isomer, which supports the key role of CoA thioesters in the metabolic inversion of profens. The inversion observed in the presence of NADPH suggests that, when the incubation is run with hepatic microsomes, a CYP450-mediated pathway is also active. In order to get more insight into the CYP450-mediated inversion pathway, we studied the effect of irradiating microsomes with a low dose of He-Ne laser radiation (0.2 J). Such irradiation caused a significant increase in inversion at all times studied and normalized the anomalous value of inversion observed at 15 min in this pathway.

Mescaline action on “memory decay” and “problem solving” behavior in the rat

The modifications of behavior caused in the rat by a chronic oral administration of mescaline have been studied in three experimental situations. In the staircase maze mescaline accelerated the spontaneous decay on the conditioned reflex (memory decay) during the period without daily training. Only the results observed at 30 mg/kg/day of mescaline were statistically significant. In a T maze two lateral alleys closed by two swinging doors, 30 mg/kg/day of mescaline increased the time spent in opening the first door. When the two doors of the lateral alleys were closed with a latch, mescaline 30 mg/kg/day, caused an increase in the time spent by the rat in opening the doors. Mescaline caused an increase in food consumption. The increase at 30 mg/kg/day is statistically significant.