Biomedical subjects

Suhita Nadkarni

Publications and source records attributed to Suhita Nadkarni.

3 recordsLinked to original sources

PubMed2005

Synaptic inhibition and pathologic hyperexcitability through enhanced neuron-astrocyte interaction: a modeling study.

Recently, upregulation of metabotropic glutamate receptors (mGluRs) on hippocampal astrocytes in epileptic tissues has become part of the etiology of epilepsy and suggests the involvement of astrocytes in the disease. Through computational modeling, we have shown in previous work that upregulated mGluRs on astrocytes can give rise to positive feedback in closed loop neuron-astrocyte circuits with epilepsy-type spontaneous neuronal spiking. In this paper we further quantify the necessary degree of upregulation of astrocytic mGluRs, relate it to recent clinical and experimental studies, and address through computational modeling the role of synaptic inhibition through interneurons in this form of hyperexcitability. We conclude that inhibitive circuitry cannot tame this form of hyperexcitability.

Animals↗

PubMed2004

Dressed neurons: modeling neural-glial interactions.

Based on recent experimental data, we design a model for neuronal membrane potentials that incorporates the influence of the surrounding glia (dressed neurons). A neurotransmitter released into the synaptic cleft triggers a Ca(2+) response in nearby glial cells that spreads as a Ca(2+) wave and interacts with other synapses via the release of glutamate from astrocytes. We consider the simple case of a neuron-glia circuit that consists of a single neuron that triggers a Ca(2+) response in the glial cell which in turn feeds back into synapses of the same neuron. It is shown that persistent spiking can occur if the glutamate receptors on the astrocytes are overexpressed--a condition that has been reported from patients suffering from mesial-lobe epilepsy.

Animals↗

PubMed2003

Spontaneous oscillations of dressed neurons: a new mechanism for epilepsy?

Most modeling studies of neurons and neuronal networks are based on the assumption that the neurons are isolated from their normal environment. Based on recent experimental data we put forward a model for neurons that incorporates the influence of the surrounding glia (dressed neurons). We predict seizurelike spontaneous oscillations in the absence of stimuli for strong coupling between neurons and astrocytes. Consistent with our predictions, a signature of this enhanced crosstalk, over expression of glutamate receptors in astrocytes, has been observed specifically in epileptic tissue.

Astrocytes↗