Subcutaneous Tissue

Characteristics and Function

The subcutaneous tissue primarily comprises adipocytes (fat cells) and connective tissue. It plays a multifaceted role in:

• Thermoregulation: Acts as an insulating layer, protecting internal structures from temperature variations.
• Shock Absorption: Helps absorb shock to underlying organs and structures.
• Energy Storage: Functions as a fat cell reservoir that stores energy and produces hormones like leptin.

Anatomy and Physiology

This layer is well-vascularized and rich in blood vessels. The thickness of the subcutaneous tissue varies across different body parts, from less than 1 millimeter in areas like the eyelids to over an inch in the abdomen and buttocks. It is interconnected with muscle through a dense layer of deep fascia.

Subcutaneous tissue is a common site for drug administration due to its slow absorption rate. It is beneficial for:

• Long-term medication, Such as insulin and growth hormones.
• Acute treatments: Including epinephrine and morphine.
• Medications administered subcutaneously are generally slower to absorb than those injected directly into a blood vessel, making this layer ideal for continuous drug absorption or low-dose treatments.