Role of Estrogen Receptors in the Hippocampal-

Neuropeptide Y Expression.

Tamara Dennis

Dr. Jana Velíšková

Albert Einstein College of Medicine

Introduction

Objective To determine the estrogen receptor (ER) type

responsible for increasing the Neuropeptide Y (NPY) expression.

Hypothesis The ER is responsible for the expression of NPY.

Introduction

What are Estrogen Receptors? Estrogen receptors (ER) are intracellular proteins. The hormone estrogen binds to these receptors. There are two types of estrogen receptors, ER and ER .

What is NPY? NPY is a powerful inhibitory peptide. It is located all over the brain. We are interested in the expression of NPY in the hippocampal hilar region. It is responsible for regulation of neuronal excitability, neuroprotection, feeding behaviors, circadian rhythm.

Hippocampus in a human

Hippocampus in a rat

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are needed to see this picture.

Role of NPY

It has been shown that during Status Epilepticus (SE) interneurons containing NPY are preferentially lost.

Interneurons are important inhibitory neurons. If they are lost, hyperexcitability and epileptogenesis occurs.

Increase of NPY in the hilus attenuates SE-induced damage to the hippocampus.

Methods & Procedures

Ovariectomy Treat animals with DPN Perfusion with formaldehyde & saline Soak brains in formaldehyde overnight Change solution to 30% sucrose Immunohistochemistry Cell counting under the microscope

Drug

DPN 2,3-bis(4-Hydroxyphenyl)-propionitrile ER agonist C15H13NO2

Perfusion

Immunohistochemistry

Histology Immunochemistry Day 1 1. 50 l H2O2 + 5 ml PBS 30’

2. Wash 3x 5’ with PBS

3. 200 l BSA + 200 l Triton + 500 l NGS + 4.228 ml PBS (double) 60’

4. 5 ml of solution 3 + 1.5 l of NPY antibody

Day 2 1. Wash 3x 5’ with PBS

2. 100 l BSA + 25 l anti-rabbit antibody + 4.9 ml PBS 60’

3. Prepare AB: 1drop of A and 1 drop of B in 5 ml PBS, Shake 30’

4. Wash 3x 5’ with PBS

5. Apply AB solution 60’

6. Wash 3x with PBS 5’

7. DAB 8’

Results

Due to the time required to do this experiment there are no results as of yet.

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Acknowledgements

Dr. Jana Velíšková Dr. Sat Bhattacharya Hong Wong Albert Einstein College of Medicine Harlem Children Society