Biomedical subjects

F Vives

Publications and source records attributed to F Vives.

39 records · Page 3Linked to original sources

PubMed1979

Insulin effects on glucose utilization by human lymphocytes.

In recently isolated human lymphocytes, no effect of insulin on (U-14C) glucose incorporation into CO2, triglycerides and glycogen, was found over a wide range of insulin concentration. The rates of glucose oxidation, synthesis of triglycerides and synthesis of glycogen are much lower than those observed in chicken and rat adipocytes. The authors discard the possibility of using the human lymphocyte as an instrument in the study of the insulin action on normal and altered human physiology.

Glucose↗

PubMedDate not supplied

Differential effects produced by an anticholinergic on the neuroleptic inhibition of motor behaviour and self-stimulation of the prefrontal cortex in the rat.

A specific dopamine receptor blocker, spiroperidol (0.016, 0.032, 0.064 and 0.128 mg/kg) alone or in combined treatment with the centrally acting anticholinergic, dexetimide (0.5, 1.0 mg/kg) was given intraperitoneally to rats pressing a lever for brain self-stimulation through electrodes implanted in the medial prefrontal cortex. The same treatment was also given to rats in which the spontaneous motor behaviour was measured. Spiroperidol produced a dose-related inhibtion of both self-stimulation and spontaneous motor activity. Dexetimide, given to spiroperidol treated rats, was able to antagonize the motor impairment produced by spiroperidol, but prefrontal cortex self-stimulation remained decreased. These data support the suggested role for dopamine in self-stimulation of the prefrontal cortex in the rat.

Animals↗

PubMedDate not supplied

Effects of medial prefrontal cortex stimulation on the spontaneous activity of the ventral pallidal neurons in the rat.

The neural connections from the medial prefrontal cortex to the ventral pallidum were investigated in urethane-anesthetized rats. Extracellular recordings were made from 124 spontaneously firing neurons in the ventral pallidum while the medial prefrontal cortex was electrically stimulated. The most frequent response to prefrontal cortex stimulation was inhibition of the firing rate of 72.3% of the neurons with orthodromic response (mean latency: 14.4 +/- 1.6 ms). Excitatory responses were found in 27.7% of the neurons with orthodromic response (mean latency: 8.5 +/- 1.4 ms). Frequency histograms of latencies were unimodal in both types of responses. Fifty-nine neurons (47.6% of the total tested) showed no change in spontaneous firing after medial prefrontal cortex stimulation. The electrophysiological results support previous anatomical findings of connections between the medial prefrontal cortex and the ventral pallidum. These projections play a predominantly inhibitory role in the spontaneous activity of ventropallidal neurons, and show topographical organization. This inhibition may modulate the motor performance of motivated behaviors.

Action Potentials↗