Dr. Zuperku’s main research focus has been on the brainstem mechanisms underlying the control of breathing in vivo. These studies also include the mechanistic effects of volatile anesthetics on neurotransmission in respiratory neurons that provided important insights into which neurotransmitter systems (GABAergic, glutamatergic, serotonergic) are most affected by clinically relevant concentrations of isoflurane and sevoflurane. The most recent studies involve the mechanisms underlying opioid-induced respiratory depression, and especially analysis of neurons at a site within the respiratory neuronal network that is highly sensitive to opioids and can result in apnea at clinically relevant concentrations. These studies led to the discovery of a primary brainstem site within the pons that controls breathing frequency. These studies have been funded by VA Merit Review and NIH RO1 grants for over three decades.
Specific areas of interest include respiratory neuronal rhythm and pattern generation, neurotransmission, neuromodulation, connectivity, pulmonary mechanoreceptors, arterial and central chemoreceptors, and neuropharmacology at the neuronally level.
The main techniques used include: extracellular single neuron spike recordings with multi-electrode probes, moving-time averages of nerve recordings, multibarrel micropipettes for simultaneous neuronal recording and microejection of neurotransmitter agonists and antagonists, spike sorting, cycle-triggered histograms, electrical stimulation of nerves and brainstem nuclei, antidromic activation and collision, spike-triggered averaging, and mechano- and chemoreceptor stimulation.