In order for HSP60 to act as a signal it must be present in the extracellular environment.

Cells that produce paracrine factors secrete them into the immediate extracellular environment.

More recently due to the significance of the extracellular environment and technological developments, studies involving 3D tissue systems, including living organisms, have become more common.

When the extracellular environment is hypertonic, cells lose water and consequently, shrink.

This forms a tough barrier between the intracellular components and the extracellular environment, which has to be penetrated.

This is important in keeping the external concentration of the hormone low in the extracellular environment where many hormones are sensed.

It is limited by the inhibitory influences of the glial and extracellular environment.

Specific proteases act on the protein in the extracellular environment when cells have a reason to move or change their surroundings.

Similarly, homeostatic mechanisms that regulate the extracellular environment may be affected by characteristics of the cell surface.

The molecules thus released into the extracellular environment include: