Osmolarity to Affect the Behavior of Hydra Vulgaris, Study Suggests

Jan, 2021 - By SMI

According to a new collaborative research study by the researchers of Columbia University and the Marine Biological Laboratory (MBL) has reported to decode the neural code of Hydra's regular behavior, known as contraction bursts, where the torso of the Hydra shrinks down and expands outward, time and again. The researchers observed that osmolarity (concentration of dissolved particles in the surrounding water) impacts the activity of a neural circuit in one of Hydra's nerve nets, which further stimulates a unique set of muscle cells, in order to contract the torso. Hydra vulgaris is a small, freshwater organism with tentacles, which utilizes mesh of neurons disseminated throughout its tube-like body that aids in stretching, somersaulting, contracting, and feeding movements.

Rafael Yuste, senior author stated, “One by one, we want to decipher the neural and muscular activity behind each of Hydra's behaviors. This paper is the beginning of our journey.”

In this study, researchers employed a whole-body calcium imaging to envisage Hydra's neurons and muscles, and examined whether alteration of various environmental conditions such as water body size, temperature, nutritional state, and osmolarity will impact contractions. Later, researchers observed that of the parameters, osmolarity, had an effect on contractions. Researchers further proposed that contraction burst (CB) neurons reacted to the changes in osmolarity by fluctuating the muscle activity, which further impacts the frequency of contraction.

In addition researchers also reported that including contractions, osmolarity also influenced the frequency of Hydra’s detachment and repositioning the tube foot, to move to a new location. Moreover, researchers concluded that they will continue to explore the phenomena of how and why this happens that will further help to interpret a more complex behavior such as somersaulting behavior of Hydra.