Earthworm, Lumbricus Terrestris: A Novel Microinjection Vasculature In vivo Invertebrate Model

Area of Science:

• Biomedical Research
• Invertebrate Models
• Vascular Biology

Background:

• Vertebrate models in research face limitations including cost, ethical concerns, and review times.
• There is a need for accessible and cost-effective alternatives for preliminary biological studies.

Purpose of the Study:

• To introduce the earthworm as a viable, low-cost invertebrate model for preliminary vasculature research.
• To provide a detailed protocol for compound administration into the earthworm's vascular system.

Main Methods:

• Utilizing the earthworm's accessible dorsal and ventral vessels and pseudo hearts for surgical study.
• Developing a protocol for anesthetizing earthworms and performing surgical incisions.
• Fabricating and employing custom micropipettes with micropositioners and microinjectors for precise compound delivery.

Main Results:

• Demonstrated the feasibility of administering compounds into the earthworm's vascular system with high repeatability.
• Established a method for achieving large sample sizes with minimal compound volumes.
• Highlighted the earthworm's closed circulatory system and hemoglobin structure as advantageous for certain studies.

Conclusions:

• The earthworm presents a practical, low-cost alternative for preliminary vasculature research, overcoming common limitations of vertebrate models.
• Mastery of the presented microinjection techniques enables cost-effective, large-scale studies.
• This model is particularly suitable for initial investigations requiring high sample sizes and minimal compound usage.