major effector mechanisms are:
• ADH (anti-diuretic hormone).
Control of Water Input : Thirst
Thirst is a mechanism for adjusting water input via the GIT.
of Water Output : ADH & the Kidney
ADH provides a mechanism for adjusting water output via the
kidney. Note that ADH is often called 'vasopressin' - this term
refers to the vasoconstrictive properties of very large doses
('pharmacological doses') of the hormone
Both thirst and ADH
can increase when water is needed by the body and the usual
physiological outcome is to repair the water deficit. These
effector mechanisms are discussed in the next 2 sections. The
whole system for control of water balance as outlined in this
chapter is frequently referred to as "the thirst-ADH
mechanism" though this really only refers to the effector
part of the control system.