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Biomedical subjects

R Cuocolo

Publications and source records attributed to R Cuocolo.

At least 19 recordsLinked to original sources

Evidence for a differential interaction of buprenorphine with opiate receptor subtypes controlling prolactin secretion.

We studied the effects of various doses of the opiate derivative buprenorphine on serum prolactin levels and whether these effects could be counteracted by pretreatment with the opiate receptor blocker naloxone. The administration of increasing doses of buprenorphine exerted a dual effect on serum prolactin levels. At low doses (3, 10 and 30 micrograms/kg) this agent increased serum prolactin levels. This effect disappeared with increasing doses (100 and 300 micrograms/kg), and at the highest doses (1000 and 3000 micrograms/kg) the levels of serum prolactin decreased. Naloxone (30 mg/kg) decreased serum prolactin levels and reversed both the stimulatory and the inhibitory action of buprenorphine. These data are compatible with the hypothesis that buprenorphine could interfere with two different, but inter-dependent receptors: at low doses the oripavine derivative could act at one receptor site to cause an increase of serum prolactin, whereas at higher doses it could interact with a second site of lower affinity that is responsible for the inhibition of prolactin secretion. When buprenorphine (at high doses) activates the lower affinity site, the interaction with this receptor counteracts and reverses the effects of the high affinity site. On the basis of this hypothesis, naloxone should block both receptors.

Animals↗

Propofol infusion and auditory evoked potentials.

The effects of propofol on auditory evoked potentials (brainstem and middle latency responses) were recorded in six patients. Two different infusion rates were used, 54 and 108 micrograms/kg/minute. Effects on brainstem responses were not found. Regression of amplitude and latency of middle latency auditory potentials were dose related (p less than 0.01).

Adult↗

Photooxidation of epinephrine sensitized by methylene blue as an assay for the evaluation of alpha-mercaptopropionylglycine as a free radical scavenger.

Free radicals, which are instable intermediates of some biochemical reactions, are produced everywhere in the living matter. They may induce cell membrane lipid peroxidation, with non reversible letal effects. Alpha-mercaptopropionylglycine capability of scavenging free radicals has been tested. H2O2 has been used as a free radical donor under actinic light, epinephrine oxidation to adrenochrome as a revealing system and methylene blue as sensitizing agent. alpha-MPG at 6 mM concentration showed the maximal inhibition of free radical formation in our system. Higher concentrations were unable to produce further inhibition.

Amino Acids, Sulfur↗

[Preparation of a polyvalent antiserum specific for human muscle proteins. I. Muscle extraction: a macromethod and a micromethod].

Protein metabolism may be upset dramatically by several pathological condition such as starvation, malnutrition, surgical stress. Serum proteins have been investigated in many works but very few studies exist about muscle and organ proteins. This article describes two methods for extraction of muscle water soluble proteins: a macromethod that uses some hundred grams of tissue, and a micromethod that starts from a little muscle biopsia. Extracts have been tested for protein content by electrophoresis on cellulose acetate and isoelectrofocusing on polyacrylamide gel and have shown a rich variety of protein fractions.

Animals↗

[Preparation of a polyvalent antiserum specific for human muscle proteins. II. Animal immunization and purification of the antiserum].

A new preparation technique to raise rabbit antisera against human water-soluble muscle proteins is presented. Immunization, blood collection and further purification of antibody fraction in serum are described in detail. The present method is fast and easy to perform; chromatography and dialysis are not required and antisera so produced lend themselves to immunoelectrophoretic evaluation of human water-soluble muscle proteins.

Animals↗

An improved immunoelectrophoretic methodology for the evaluation of protein caloric malnutrition.

An improved technique of two dimensional immunoelectrophoresis of serum proteins on gelatinized cellulose acetate for routine evaluation of protein nutritional state is described. The method, which allows the estimation of more than 30 protein fractions, proves extremely useful in monitoring the effectiveness of total parenteral nutrition and protein metabolic conditions. Sera samples from healthy subjects and cachectical neoplastic patients have been examined and preliminary results are reported.

Beta-Globulins↗

Effects of althesin and ketamine on resting and stress stimulated adrenocortical activity in rats.

The effects were studied of two i.v. anaesthetics (Althesin and ketamine) on resting and activated adrenocortical function in the rat. Small doses of Althesin and ketamine comparable to those required to produce induction of anaesthesia in man evoked adrenocortical stimulation, but the stressing effects of ketamine were more prolonged. During deep anaesthesia with either anaesthetic there was an inhibition of pituitary adrenal activation induced by handling and surgery. However, during recovery, ketamine was associated with intense and prolonged adrenocortical stimulation. The stress of laparotomy in control rats and in rats pretreated with the anaesthetics caused a depletion of noradrenaline in the hypothalamus; this suggests that both anaesthetics inhibit adrenocortical activation by mechanisms different from adrenergic inhibition.

Adrenal Cortex↗