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J L Valatx

Publications and source records attributed to J L Valatx.

At least 55 records · Page 3Linked to original sources
PubMed1985

Effects of hypothalamic paraventricular lesions on sleep in rats.

In 7 rats 45-86% of the hypothalamic paraventricular tissue was destroyed by electrolytic coagulations. During the first 6 post-operative days the mean daily amount of paradoxical sleep was significantly decreased, and the circadian sleep-walking cycles of paradoxical and slow-wave sleep were abolished. The slow-wave sleep rhythm then became normal, but in paradoxical sleep the acrophase was shifted, and in one animal the rhythm was completely inversed. Thus the hypothalamic paraventricular nucleus seems to play a modulating role in the production of paradoxical sleep and in the generation of its rhythm.

Animals↗
PubMed1982

The locus coeruleus: a quantitative and genetic study in mice.

A fluorescence histochemical study of the pontine catecholaminergic (CA) neurons of two inbred strains of mice, BALB/c (C) and C57BL/6 (B6) and their F1 hybrids revealed that the total number of the fluorescent cells in the C strain was 38% lower than that of the B6 strain. In F1 hybrids, the total number of neurons was not statistically different from that of the B6 parent. During the development from birth to adulthood, the same quantitative differences between strains were observed.

Animals↗
PubMed1981

Increased sleep time in the offspring of caffeine-treated dams from two inbred strains of mice.

Dams from two inbred strains of mice (C57BR and BALB/c) were treated with caffeine in solution in their drinking water during gestation. Doses of caffeine used corresponded to about 60, 80 or 100 mg/kg/day; controls received tap water. The offspring (as adults) revealed a significantly increased sleep time following caffeine treatment, but primarily as slow wave sleep in the males of the BALB/c strain and paradoxical sleep in the females of the C57BR strain. BALB/c females and C57BR males were relatively unaffected. These results, and in particular the sex differences, are discussed in terms of a possible central site of action of caffeine.

Animals↗
PubMed1981

Gestational caffeine modifies offspring behaviour in mice.

Dams from two strains of mice, BALB/c C57BR were tested during gestation with caffeine, at doses of about 60, 80 and 100 mg/kg/day, in their drinking water. The resulting offspring were behaviourally tested over a 6-month period commencing at age 9 months. When compared with controls, mice from dams that had received caffeine demonstrated longer latencies in a passive avoidance test, and differences were also noted for female C57BR offspring in activity and habituation measures. Having controlled as far as possible for post-natal maternal and environmental effects, the most likely conclusion is that caffeine has a direct pharmacological action on the foetus, and should therefore be classed as a behavioural teratogen in mice.

Animals↗
PubMed1979

Strain differences in amphetamine sensitivity in mice. I. A diallel analysis of open field activity.

Experiments are reported which show that 1 mg/kg of d-methylamphetamine HCl induced hyperactivity in pigmented strains (C57BR, C57BL/6, and SEC) and hypoactivity or no change in albino strains (BALB/c, A, and AKR) of mice. In F1 hybrids, the B6 genotype was partially dominant over BR and C, and BR over C. In animals back-crossed to C parents widespread distributions with two peaks were obtained in control experiments, and amphetamine induced hyperactivity in 38% of the albino population, and hypoactivity or no significant change in 45% of the pigmented one. This genetic study indicates that genes influencing locomotor activity are independent from those influencing amphetamine sensitivity. From results obtained in back-crosses and C57BL/6-c2J mice, the albino gene does not seem to be involved in the hypoactive effect of amphetamine.

Animals↗
PubMed1979

Strain differences in amphetamine sensitivity in mice. II. Overcompensation of paradoxical sleep after deprivation in two C57 strains.

d-Methylamphetamine (1--4 mg/kg) induced wakefulness for 3--5 h followed by paradoxical sleep (PS) rebound in C57BR, C57BL/6, and BALB/c mice. Slow-wave sleep (SWS) and PS suppression time were proportional to the given dose and different among strains. It was also dependent on the time of injection. Later PS rebound was significant in C57 strains, and in certain cases greater than PS loss, whereas rebound was small in BALB/c mice and PS loss was not completely compensated.

Animals↗
PubMed1977

[Phasic activity in rats].

At the central level, in the rat, phasic activity has been recorded during paradoxical sleep and in acute conditions after injection of reserpine or parachlorophenylalanine. At the external level, during paradoxical sleep, the extraocular muscles lateral rectus, superior rectus and superior oblique are activated in both plastic and tonic manners. The muscles of the whiskers are also activated; these muscular activations are more often than not synchronous with the eye movements (80%). The time distribution of these ocular movements is homogenous. Reserpine induces phasic muscular activations of the extraocular muscles.

Animals↗
PubMed1976

[Y-maze learning in two strains of mice. Effects of instrumental and pharmacologic sleep deprivation].

Effects of instrumental and pharmacological deprivation of sleep on Y-maze learning have been studied in two inbred strains of mice (C57BR/cd/Orl and C57BL/6/Orl), having identical sleep rhythms, but mainly differing in their ability to learn. Administration of alpha-methyl-DOPA (100 mg/kg) provokes complete suppression of paradoxical sleep (PS) for 9-11 h. Injection immediately after each training session over the first 5 days caused a delay in acquisition of an active avoidance task in C57BR mice. Treated C57BL/6 mice exhibited a significant facilitation of acquisition. Similar results were obtained by instrumental deprivation of sleep for 10 h.

Animals↗
PubMed1975

[Action of alpha-methyl-dopa on waking-sleep cycles in two inbred strains of mice, C57BR and C57BL/6 (author's transl)].

The effects of alpha-methyl-Dopa at several dose levels on waking-sleep cycle of 175 mice from two inbred strains (C57BR and C57BL/6) have been studied. The results showed that each dose (25, 50, 100, 200 and 400 mg/kg), of alpha-methyl-Dopa completely suppresses paradoxical sleep (PS), after a period of sedation. Duration of PS inhibition varied as a function of dose, time of injection, and strain of mice. Using a multiple injection schedule of one injection per day for 5 consecutive days, there was suppression of nocturnal PS followed at the 4th day by rebound during day light hours.

Animals↗