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M Valli

Publications and source records attributed to M Valli.

At least 109 records · Page 6Linked to original sources
PubMed1982

[Neuro-endocrine effects of chronic clonidine administration in rats].

Neuroendocrine effects of chronic clonidine administration - which has been proposed as antimanic drug - have been evaluated in the female rat for a twenty one days period at the following doses : 0,5 ; 5 ; 25 and 50 micrograms.kg-1.day-1. No modification of the evolution of the oestrus cycle was observed, whereas pituitary hormones (PRL, FSH and LH) plasma levels were not statistically modified. The results of this study are opposed to those frequently observed with classical neuroleptic drugs.

Animals↗
PubMed1982

[Absence of effects of sodium valproate on the estrous cycle of the rat].

Regarding interrelationships between epilepsy, antiepileptic drugs and neuroendocrinological events, sodium valproate effects on estrous cycle of the rat have been performed by daily vaginal smears for twenty one days with 200, 100, 20 and 10 mg per kg bodyweight. Our data showed that sodium valproate did not significantly modify the evolution of estrous cycle even if intracerebral GABA content increase has been reported to influence hormonal secretions.

Animals↗
PubMed1981

Circadian effect on carbamazepine kinetics in rat.

The purpose of the present study was to investigate whether the time of day (24 h) at which carbamazepine is administered influences its pharmacokinetics in the rat. The pharmacokinetics of a single, 100 mg . kg-1 bodyweight per os, dose of carbamazepine were studied at four different fixed time points of a 24-hour period (i.e. 10.00, 16.00, 22.00 or 04.00 h) in Wistar AF-SPF adult male rats maintained under controlled environmental conditions (LD: 18.00 - 06.00h) during October 1978. The total plasma levels and the unbound fraction were measured according to an immunoenzymatic method (EMIT). The effects of fasting were also investigated. The data shows circadian variations of pharmacokinetic parameters: the maximum peak concentration and the maximum time to reach this peak was observed when the drug was given respectively at 16.00h and at 10.00h. The elimination half-life varied from 15.15 hours at 16.00h to 10.48 hours at 22.00h. The observed variations may be related to: daily fluctuations of absorption or binding of the drug; diurnal variations of the hepatic drug metabolizing enzymes responsible for the inactivation; and/or diurnal variations in excretion rate of the drug.

Administration, Oral↗
PubMed1981

[Possible effects of propranolol on the estrous cycle of the rat].

Propranolol effects on oestrous cycle of the rat have been studied by daily vaginal smears for twenty one days with doses nearby similar to those used in psychiatric disorders (e.g. 3, 10 and 30 mg.kg(-1). Our data showed that propranolol did not modify the evolution of of oestrous cycles even if plasma prolactin levels have been increased by the highest dose used (30 mg.kg(-1).

Animals↗
PubMed1980

[Effects of cimetidine on estrus cycle in the rat].

Statistical study of Cimetidine effects on estrous cycle of the rat have been performed, by daily vaginal smears, for twenty one days with doses nearly similar to those used in human therapy. Our data showed that Cimetidine did not significantly modify the evolution of estrous cycles.

Animals↗
PubMed1979

[Modification of curarization after acute administration of 2 antiepileptic drugs].

In rats anaesthetised with sodium pentobarbital the previous administration of a single dose of an anti-epileptic agent (carbamazepine or sodium valproate) significantly increases the curarising action of two short-action curare-like agents--pancuronium bromide and fazadinium bromide. It seems that this potentialisation of curare action might be the result of either a pharmacokinetic interference (competion for plasma protisen receptor sites), or due to a summation of depressor actions at the neuromuscular level, especially through changes in the levels of GABA and/or cAMP.

Animals↗
PubMed1979

[Circadian variations of the plasma proteins in the adult male rat under natural synchronisation (author's transl)].

Circadian rhythms of blood total proteins, albumin, alpha 1-, alpha 2-, beta- and gamma-globulins were documented in 80 Wistar SPF adult male rats, synchronized by natural light (06.00-18.00 h) and darkness (18.00-06.00 h) during the month of October 78. Blood was sampled at four fixed time points in the 24 h scale (i.e. 04.00, 10.00, 16.00 or 24.00 h). Total proteins, albumin, alpha 2- and gamma-globulins showed a statistically significant rhythm with a maximum at 04.00 h. The data obtained in anaesthetized rats under artificial synchronization and in man are compared, taking into account that the rat is a nocturnally active rodent. The present work partially confirms the hypotheses of previous chronopharmacological studies, thus e.g. curarizing substances have a mimimum activity when the protein plasma level, especially albumin, is the highest.

Alpha-Globulins↗
PubMed1978

[Chronopharmacology of pancuronium in rats anesthetized by CT 1341 (Alfatésine)].

A circadian variation in the curarizing ability of pancuronium bromide (Pavulon) has been documented in an homogenous group of 100 Wistar AF-SPF adult male rats anaesthetized by the steroid anaesthetic althesin (Alfatésine, CT 1341). Animals were maintained at 24 +/- 2 degrees C and synchronized with natural light 06.00 to 18.00 and darkness (october 1977). We observed significant circadian rhythms for both of these agents: first the induction of anaesthesia by althesin was markedly pronounced at 15.30 and varied with season. Secondly the maximum effect of pancuronium was recorded at 08.00. When rats were anaesthetized by sodium pentobarbital under similar experimental conditions but during a different season (january to may) we observed a similar circadian rhythm for pancuronium. These data indicate that: a) the type of anaesthesia used in the protocol may not be of importance in demonstration of a curarizing rhythm in the rat but, b) the possibility of a seasonal component being present and effecting this rhythm needs to be investigated.

Alfaxalone Alfadolone Mixture↗
PubMed1977

Osteogenesis imperfecta: morphological, histochemical and biochemical aspects. Modifications induced by (+)-catechin.

Two patients affected with two different forms of Osteogenesis Imperfecta were examined in order to study collagen and glycosaminoglycans (GAGs) in skin and iliac crest cartilage. A sharp decrease of the galactosamine to glucosamine ratio due to a reduced content of chondroitin sulfate was evidenced in both patients. Moreover the structure of proteoglycans appeared altered, this being more evident in the severe form of the disease. Morphological examination in light and electron microscopy of cartilage of the less severely diseased patient showed that GAGs in the extracellular matrix did not present regular connection with collagen fibers. Chondrocytes, elongated and disorderly scattered, showed large lipidic inclusions and, on histochemical basis, were devoid of UDPG dehydrogenase activity. Treatment with (+)-catechin produced an improvement, in both patients, of the biochemical pattern of collagen and GAGs. Similarly a shift of the cellular activity and of the matrix morphology towards normality was observed in the investigated cartilage of the less severely affected patient.

Adolescent↗