Biomedical subjects

D Lekić

Publications and source records attributed to D Lekić.

4 recordsLinked to original sources

PubMed1992

Pain and tooth pulp evoked potentials.

The purpose of this study was to verify whether the late components (N 140) of TPEPs were a reliable index of pain intensity. In the group with acute pain, except for higher amplitudes of the second negative wave, the plateau phenomenon has been noted. Analgesic and placebo effects indicated that the method used offers more objective than subjective components, because the real value of amplitudes is about 10% of control values for analgesic and between 60 and 70% for placebo. Shorter latency periods were observed in all parts of evoked potentials in the patients suffering from trigeminal neuralgia, as occurrence of a greater number of waves; while amplitudes on the affected side were significantly higher than on the healthy side.

Dental Pulp↗

PubMed1991

Tooth pulp evoked potentials (TPEPs) in multiple sclerosis patients.

The purpose of this study was to determine possible changes of the tooth pulp evoked potentials in patients with multiple sclerosis, and to compare these with other types of evoked potentials, in the same patients. The results showed TPEP changes in all multiple sclerosis patients. In 12 patients the changes were observed on both sides, while in 6 on one side only. It is interesting to note that the second negative wave was characterized by two peaks. The first peak possessed latency of approximately 125 ms that was significantly shorter than in the control group. The second peak appeared after about 195 ms. The significant prolonged latency of the second negative wave was observed in 100% of TPEPs, 95% VEPs and 72% AEPs. In only one case the changes were observed in TPEPs, while VEPs and AEPs were normal. It could be concluded that TPEPs, as well as other types of evoked potentials, are a sensitive indicator of the demyelination process.

Adolescent↗

PubMed1977

Substance P selectively blocks excitation of Renshaw cell by acetylcholine.

In cats, under Dial anaesthesia, Renshaw cells were excited by microiontophoretic applications of acetylcholine (ACh), aspartate, and glutamate. Substance P, in small doses (10-30 nA), selectively abolished the responses to ACh, leaving the discharges evoked by the amino acids unchanged or enhanced. Higher doses (greater than 50 nA) depressed all responses, but those evoked by amino acids went down last and recovered sooner. By contrast, neither synaptic responses to ventral root stimulation nor spontaneous discharges were affected by substance P, presumably owing to the high efficacy of synaptic transmission and the presence of diffusion barriers around junctional sites.

Acetylcholine↗

PubMed1977

Presynaptic depression of synaptic response of Renshaw cells by adenosine 5'-monophosphate.

The action of AMP (adenosine 5'-monophosphate) on synaptic transmission of Renshaw cells has been studied in cats under Dial anaesthesia. AMP applied iontophoretically reversibly reduced synaptic responses of Renshaw cells evoked by stimulation of ventral roots, as well as their spontaneous firing; however, there were no marked effects on discharges of these cells caused by iontophoretic application of acetylcholine, asparatate, and glutamate. On the other hand, AMP had no comparable effect on synaptic responses of dorsal horn interneurones evoked by stimulation of dorsal roots or their spontaneous discharges.

Adenosine Monophosphate↗