Difference Between Autocrine and Paracrine

The key difference Between Autocrine and Paracrine is that the autocrine refers to the action of hormones or other secretions on the same cells that they secreted while the paracrine refers to the action of hormones or secretions on the cells nearby the production cells.

Endocrine glands secrete hormones into the extracellular environment. These hormones are chemicals that act as chemical messengers to facilitate communication between cells and tissues throughout the body. Once they are released, they diffuse into the bloodstream and circulate through the veins and capillaries. Therefore, there are three main types of hormones namely peptide hormones, lipid hormones, and monoamine hormones. However, the action of each hormone is different. Therefore, some acts on the cells by which they secreted, while some travel through the bloodstream far away from the production site and act on different cells and tissues.  And some acts on the nearby cells. Based on these actions, there are three types namely, autocrine, endocrine and paracrine hormones.

CONTENTS

1. Overview and Key Difference
2. What is Autocrine
3. What is Paracrine
4. Similarities Between Autocrine and Paracrine
5. Side by Side Comparison – Autocrine vs Paracrine in Tabular Form
6. Summary

What is Autocrine?

The term ‘Autocrine’ refers to the mode of action of hormones or other secretions when they act on the secreted cells themselves. The ligands released by the cells target binding with the receptors located on the surface of the same cells.

Therefore, this type of cell signalling is important for many processes in our body including development, cancer therapy, etc.

What is Paracrine?

Paracrine refers to when the hormones or other secretions acting on the cells near the production site. Ligands released by the endocrine cells bind with the receptors on the surface of neighboring cells.

Moreover, it is a type of cell communication that hormones use to communicate between closely located or neighboring cells.

What are the Similarities Between Autocrine and Paracrine?

• Autocrine and paracrine are two modes of action of hormones or other secretions.
• The release of ligands and binding with receptors occur in both cases.
• Both are related to cell communication and cell signalling.

What is the Difference Between Autocrine and Paracrine?

Autocrine hormones affect the cells themselves that they produced. Paracrine hormones affect the neighboring cells. Both are important for cell signalling and communication. The below infographic presents a side by side comparison of the difference between autocrine and paracrine.

Summary – Autocrine vs Paracrine

Autocrine and paracrine refers to the processes of cell signalling to the cell itself and to neighboring cells respectively. Concerning hormones, autocrine is the mode of action of a hormone that binds with the receptors on the same cell surface and affects the cell that produces it. On the contrary, paracrine hormone binds with the receptors on the surfaces of nearby cells and affects the functions of those cells. This is the difference between autocrine and paracrine.

Reference:

1.“Introduction to Cell Signaling.” Khan Academy, Khan Academy. Available here  
2.Learning, Lumen. “Biology for Majors I.” Lumen, Open SUNY Textbooks. Available here 

Image Courtesy:

1.’Figure 09 01 01’By CNX OpenStax  (CC BY 4.0) via Commons Wikimedia 
2.’Cell signalling’By Doublethink – Own work, (Public Domain) via Commons Wikimedia