Question

what happen if vasopressin is deficient in the human body

Answer 1

vasopressin, also called antidiuretic hormone, hormone that plays a key role in maintaining osmolality (the concentration of dissolved particles, such as salts and glucose, in the serum) and therefore in maintaining the volume of water in the extracellular fluid (the fluid space that surrounds cells). This is necessary to protect cells from sudden increases or decreases in water content, which are capable of interfering with proper cell function. Normal serum osmolality ranges from about 285 to 300 milliosmoles per kilogram (mOsm/kg) in healthy people. Vasopressin and a hormone called oxytocin evolved from a single primordial neurohypophyseal hormone called vasotocin, which is present in lower vertebrates

Answer 2

Vasopressin is a hormone that regulates osmality [concentration of amount of salt and glucose].
Deficiency of ADH is usually due to hypothalamic-neurohypophyseal lesions (central diabetes insipidus) or insensitivity of the kidney to ADH. These patients, if untreated, have the predictable result of dehydration, hyperosmolality, hypovolemia, and eventual death in severe cases.