Dr. Patrick Nahirney

Introduction

Dr. Patrick Nahirney is a Professor of Anatomy and Histology in the Division of Medical Sciences. He teaches human gross anatomy and histology to first and second year undergraduate medical students in the Island Medical Program and conducts research on neurogenesis and neuromuscular disease. He has a particular interest in providing a structural and molecular framework that relates to a number of human diseases including Alzheimer's disease, stress-induced memory loss, Nemaline myopathy, Duchenne muscular dystrophy as well as the development of novel strategies for muscle and nerve tissue engineering and regeneration of injured tissues.

Research

 "The goal is to understand how stressors and neurological diseases impact learning and memory processes."

Synapses in the brain play key roles in neuronal communication and altered synaptic function is believed to underlie a number of neurological disorders.

It has long been known that the hippocampus plays a role in learning and memory – it has become of extreme interest since changes in pyramidal, granule, interneuronal and glial cells occur in response to stressors, diseases and experimental treatments, and correspond to changes in spatial learning and memory.

Surprisingly, however, data is lacking on the specific subcellular structure of synapses in the hippocampus, and the changes that occur at the level of the synapse to various stressors and treatments.

This research examines how maternal stress and ethanol affect in utero and postnatal development of synapses in the hippocampus. Clinical evidence in humans suggests a strong link between prenatal stress and childhood disorders such as autism, fetal alcohol syndrome and schizophrenia.

To further these studies, my research will also test how exercise can reverse the effects caused by these stressors during postnatal life. Data from this research will shed new light on how prenatal stress affects synapses made by hippocampal neurons and will provide a testable model system to ascertain the effectiveness of treatments for these neurological disorders.

Shown above is a high magnification transmission electron micrograph of a branched spine making two synaptic contacts (*) with presynaptic terminals. The spine and dendrite of the postsynaptic granule cell neuron have been pseudocolored red. Vesicles containing neurotransmitters fill the presynaptic terminals. x50000.

Mito: mitochondria, MT: microtubule, Pre: Presynaptic terminal, SER: Smooth endoplasmic reticulum