Italian crested newt
When newts are inactive or in oxygen-rich environments, respiration can be done through their skin which accounts for 74% of the cutaneous respiration. However, oxygen-poor environments, such as stagnant ponds, pose a threat to the survival of larval newts. This is because oxygen molecules do not readily dissolve in water, and as "T. carnifex" is an immobile animal, extracting oxygen from water is difficult. Newts consequently have external gills at birth that persist until metamorphosis, which assists survival in low-oxygen conditions.
Italian crested newt
Arginine, vasotocin, and adrenocorticotropic are hormones secreted by the adrenal glands and are a key component in a newt's regulation of water. In contrast to prolactin, which decreases osmotic permeability, vasotocin increases the permeability and is secreted during the summer months. This hormone is regulated by another major hormone – adrenocorticotropic hormone (ACTH). Arginine vasotocin not only increases cutaneous water permeability, but promotes increased cutaneous blood flow.