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Biomedical subjects

A Polleri

Publications and source records attributed to A Polleri.

At least 37 records · Page 2Linked to original sources

Lack of counteracting effect of liposomes on benserazide-induced hyperprolactinemia.

Benserazide induces an increase of serum prolactin in man, possibly as the result of an impairment of the dopamine effect on the pituitary and/or on the outer median eminence caused by the inhibition on L-dopa decarboxylase. On the other hand, liposomes obtained from bovine brain cortex phospholipids reduced serum prolactin possibly through an effect of phosphatidylserine on dopamine biosynthesis at the level of tyrosine hydroxylase. Benserazide, given orally (125 mg) to 5 normal subjects, induced an increase of serum prolactin that did not change when 300 mg of phospholipid liposomes were given intravenously 60 min later. An increase of L-dopa synthesis does not seen to be capable to overcome the effects of the decarboxylase inhibition.

Adult

Circadian periodicity of plasma prolactin in some neurological diseases.

The circadian rhythmicity of plasma PRL has been studied in some neurological diseases in which hypothalamic involvement or abnormalities of brain neurotransmitters has been postulated. 11 patients with Steinert's myotonic dystrophy, 7 with cluster headache and 10 with Huntington's chorea have been studied. By the mean cosinor procedure, a significant circadian rhythm of plasma PRL has been observed both in Steinert's disease and in cluster headache, whereas a circadian periodicity is not detectable in Huntington's chorea, a degenerative disorder affecting the basal ganglia, the hypothalamus and many other areas of the CNS.

Adult

Benserazide induces migraine attacks. Irrelevance of concomitant hyperprolactinemia.

Migrainous women underwent acute administration of sulpiride (25 mg i.v.) and benserazide (125 mg per os), both drugs increasing prolactin secretion. A similar increase in prolactin levels was found following the administration of the two drugs. A typical migraine attack was observed only in the 4 women given benserazide. These data, though being preliminary, stress the scarce or irrelevant role of prolactin in the pathogenesis of the migraine attack.

Adult

Brain cortex phospholipids liposomes effects on CSF HVA, 5-HIAA and on prolactin and somatotropin secretion in man.

Liposomes obtained from bovine brain cortex phospholipids (BC-PL), which display several effects on brain function in mice, have been administered intravenously (200 mg) to healthy subjects at various times before diagnostic lumbar puncture. HVA and 5-HIAA concentrations in CSF have been evaluated with the aim of assessing changes of monoamines metabolism. An increase of HVA occurs after 2 hours from BC-PL administration, reaching its peak after 6--7 hours. The finding is interpreted as an index of an increased turnover of brain DA. 5-HIAA changes are less impressive and a smaller increase of the metabolite is observed. They cannot correctly be related to brain changes of serotonin metabolism, since 5-HIAA originates also from the spinal cord. No effects are observed on the secretion of prolactin, but somatotropin increases sharply between 2 and 7 hours from treatment, suggesting the possibility of an activation of the dopaminergic pathway, stimulating STH secretion.

Adolescent

Sleep-wake differences in serum prolactin levels in children.

Sleep-wake differences in prolactin serum levels have been studied in 47 prepubertal children of both sexes, aged 1 to 12 years. Sampling has been made in each subject once during wake and once during sleep. The serum levels of prolactin were found to be higher during sleep than during wake (p greater than 0.01). When the children were divided into age groups, a statistically significant difference between wake and sleep was observed in all groups considered, including that with children aged 1 to 2 years. This indicates that the sleep connected rise of prolactin levels occurs very early in chidhood. No sex releated difference either in absolute hormone serum levels or in wake-sleep changes is apparent.

Age Factors

[The mode of action of neurohormones on the central nervous system (author's transl)].

We tried to understand how hypophysiotropic polypeptides could be carried into some areas of the central nervous system. Granulations of neurosecretion in the ependymal cells and the presence of releasing hormones in the cerebrospinal fluid (CSF) suggest that CSF may transport these substances between the hypothalamus and other areas in the brain. Direct connections between the hypothalamus and other parts of the brain through secreting neurons are not necessary, the CSF transmitting to the cerebral hemispheres the hypothalamic polypeptides by the ventricles at the infundibulum.

Animals

Changes in pituitary hormones serum levels in bromocryptine-treated parkinsonian patients.

In the course of a clinical trial with 2alpha-bromoergocryptin in Parkinson's disease, the serum levels of several pituitary hormones have been studied in the assumption that the drug active on nigro-striatal dopaminergic system might also interfere with hypothalamus-protuberantial neurotransmission, and have effects on the function of the pituitary. No changes in serum levels of FSH, LH, STH and TSH were detected for every dose of the drug employed. Only prolactin serum levels diminished since the beginning of the treatment, the decrease being significant (p less than 0.05 and p less than 0.01). This effect on prolactin does not change in the dose range considered. Clinical improvement was observed for doses of drugs above 15 mg/day, whereas the effect on prolactin secretion occurred with the dose of 7.5 mg/day.

Aged