Renin immunoreactivity in the human, normal and tumoral anterior pituitary

155

TIlE EFFECT OF A N G I O T E N S I N

II ON INOSITOL-I,4,5-TRISPHOSPIIATE CONCENTRATION IN THE BRAIN OF ESTROGENIZED AND NONESTROGENIZED RATS. A Lachowicz t, M Pawhkowska l, E R~bas 2, T Och~dalskJ ~ qnstJtute of Endocrinology, Dep of Experimental Endocrinology and Hormone Research, 2II Dep of Biochemistry, Umverslty of Medicine, L6d:~, Poland Angiotensin II (AnglI) has been suggested to contribute to the physiological regulation of anterior pltmtary hormone secretion, however the bmchemical mechanism whmh AngII utlhzes m transmembrane signalhng is still uncertain Recently it has been reported that AngII is revolved in the process of pituitary hyperplasia caused by estrogens There is a good evidence that estrogens can modulate AngII action in the brain In this study we examined influence o f AngII on lnosltol-1,4,5-msphosphate (IP3) content m rat pltmtary, hypothalamus and cerebral cortex homogenates m estrogemzed (E) and nonestrogenized (FIE) rats The radlolmmunoassay was used to determine IP3 concentration W e have found that AngII augmented the IP 3 concentrataon m p~tmtary, both m E and N E rats The increase o f the IP 3 being high m E rats TMs difference occurred only after 5 days treatment wxth estrogens In the hypothalamus homogenates AngII caused shghty decrease o f IP 3 concentration but thls effect was enhanced after estrogen treatment There were no changes in IP3 content m cerebral cortex homogenates, neither in E nor N E rats All these data support the hypothesis that estrogen can modulate influence of A n g l l on anterior pituitary

RENIN IMMUNOREACTIVITY ANTERIOR PITUITARY

IN TIlE

HUMAN,

NORMAL

AND TUMOR~.L

M Pawhkowskl, J Tromllas and M P Gmgard, Insmute of Endocrinology, Medical Umvers~ty ol Lodz, Poland and Department of H3stology and Embryology, Inserm U369, Faculty of Medicine Alexls Carrel, Lyon, France Although the renm-hke activity m the anterior p~ttntary gland was described m the seventms, tile studms concermng the occurrence and the cellular locahzatlon ot renm in the human p~tuttar3, and tn tile human p~tmtary adenomas are very scarce The present work deals with th~s topic Seven normal hunaan pituitaries from atttopsy and twenty human pituitary adenomas were tmrnunostamed, by the b~otm-streptavxdm-peroxzdase techmque, with polyclonal ant~sera against human renm (working dilution 1/2000) and human anterior pltmtary hormones (hGH, hPRL, h-BFSH, h-BLH, t~,-stlbunlt, 17-39 ACTH) In the normal p~tt,,tary, renm Hnmtmoreaet,v,ty was co-locahTed mainly with ACTH m the cortmotroph cells In pmmary adenornas, the renm HnmunoreactJwty was detectable m almost all cort~cotroph (5/6) and gonadotroph adenomas (4/5) It was also detectable m somatotroph adenomas (3/5) and more rarely, m prolactmomas (1/4) Since m rat, ,enHi-anglotensm system seems to be revolved m the control ot both secretion and cellular i)aohteratton ot pttmtary, ~ts posszble relevance for pathogenes~s o1 hunaan pmmary adenomas m htllllans IS discussed