Metabolic products of fasciola hepatica in liver biology and pathologj

REGULRTIO’!

OF

PHOSQIIOLIPASE

__ . __ _

ikde,+str. Kupffer cells

7. o-m0

(KC), the

-

112

tW

IA:

KUPFFER

CELLS

:b"rg. FRG

resident Tacrophages

of the

,,ve-, c2ntain

an

intracellular form of phar$holipase A? lPLA21 which rpecific~lij Cleaves arachidonic acid (AA) fr3m the c-2 PoSltlon of membrane phosPhJliPids. We avallabllity of AP ~5 th3ught t; be the rate-limitlag step in the s?nthexzs of eicosanolds. Previous studi s 00 the regularlon Of PLA* Ln reseonse to various stimuli deduced changes of PLA2 ac?:vtt.y fron. cpange: cf AA or prost.3"oid release measurea I" intact cells. These changes, however, could ccnce;vably reflect rhe c0ntribut.m of alternative rwtes generating 3~ using AA as well as regulatory iiechanisns affecting the slgnri pathway prior to PLA2 ~tsei'. TWO different mder of regulation of PLA* Ln cell-fre: preparations of KC'r using exogenous substrate were charaiterized and the data comoared wit? studies on intact cultured cells: (1) direct

tran5dUCtlOn

S178