PANHYPOPlTUlTARlSM IN THE ADULT If the panhypopituitarism develops at an early age.

Prolonged usage of reserpine is known to produce clinical symptoms like breast enlargement (even breast cancer) even in male breasts. Phenothiazone (an aniipsychotic drug) also depresses dopamine and increases PRL secretion 2. Bromocnptine, is an agonist of dopamine and cause suppression of PRL secretion In addition, it also suppresses GH secretion Bromocnptine is used extensively against acromegaly and prolaclinomas (= prolaclm secreting tumors of adenohypophysis)". PANHYPOPlTUlTARlSM IN THE ADULT If the panhypopituitarism develops at an early age. the patient becomes a dwarf and is known as the pituitary dwarf However, if panhypopituitarism appears after the growth in vertical length is complete,then there is no question of dwarfism (cf. cretin versus adult hypothyroidism) and the condition is now called adult psnhypopituitarism (pan =the whole) Two types are known, viz4 Simmond's disease and Sheeh an's syndrome Actually the adult panhypopiturtarism is Simmond's disease and Sneehan's syndrome is a special type of Simmond's disease Any condition that causes adenohypophysial destruction will lead to Simmond's disease On the other hand, after a severe shock during delivery of the child (e. g. due to post partum hemorrhage), the Sheehan's syndrome can develop in the mother (The cause of Sheehan's syndrome is acute ischemia of the adenohypophysis but the exact mechanism of the development of acute ischemia following me poslpartum hemorrhage is debatable. it may be due to spasm of the arteries supplying the adenohypophysis) The features of adult panhypopitutarism are due to lack of the various adenohypophysial hormones Thus, (i) there will be signs of thyroid, gonadal and adrenocortical deficiencies (ii) Laboratory tests will reveal, fall ofthe values of plasma levels of the hormones of those peripheral endocrine glands (thyrod /gonads/adrenal cortex) as well as those of the tropic hormones of anterior pituitary (NB. Although, the term is panhypopituitarism.the neurohypophysis is not involved). THE HYPOTHALAMIC RELEASING HORMONES In the previous discussions, it was pointed out that the hypothalamus liberates hormones (or factors) which enter the adenohypophysis via the portal system of blood supply and strongly influences the secretions ofthe adenohypophysis Below, additional informations about the releasing hormones are given Thyrotropin releasing hormone (TRH) This is a tripepide hormone. It acts on thyrotroph cells to cause secretion of TSH . As already mentioned in connection with prolactin, TRH also acts on lactotroph and has some PRLRF like activities The second messenger, for the TRH, in the thyrotroph cells, may not be cAMP it appears, Ca