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11 H Y P E R S E C m I O N OF LUTEINISING HORMONE (LH)
IN THE POLYCYSTIC OVARY SYNDROME (PC0S)A.H. B A L M , DEPT. ENWCRINOLOGY. UIDDLESEX
HOSPITAL, LONDON. WlN E M .
Hypersecretion of LH, a feature of the PCOS. is'
associated with an increased risk of infertility and miscarriage. It appears to be due to
abnormal,
non-steroidal,
ovarian-pituitary
feedback. Women receiving superovulation treatment have an attenuated mid-cycle LH surge and
are thought to secrete an excess of an ovarian
LH-inhibitory factor, which appears to be nonsteroidal, and has been termed "gonadotrophin
surge attenuating factor", although it has yet
to be isolated. Our hypothesis is that women
who hypersecrete LH are deficient in this putative factor. A novel, in-vitro, rat pituicyte
culture system was developed as a bioassay for
LH and FSH inhibitory activity in human follicular fluid. The following observations were
made: 1. Rat pituicytes autonomously secreted
FSH in serum-free medium over a period of up to
12 days. LH was only secreted after stimulation
by gonadotrophin-releasing hormone (GnRH). 2.
Recombinant human inhibin inhibited basal FSH
secretion and GnRH-stimulated FSH and LH
secretion. The time course for inhibition of
FSH was 4 hours, whilst inhibition of LH was
not seen until 16 hours in culture. 3. Human
follicular fluid contained FSH and LH inhibitory bioactivity, which remained after the
removal of steroids, but was lost when inhibin
was removed. The time course for these effects
was similar to that of inhibin. This suggested
'that the putative LH-inhibitory factor, may
infact be either inhibin or a member of the
inhibin family.
The findings are consistent with the notion
that a non-steroidal ovarian
factor may
influence
pituitary
LH
secretion.
The
experiments, however, were
not
able
to
demonst rate the presence of an LH-inhi bi tory
factor distinct from inhibin.
12
ENDOTHELlALCELL ACTIVATION IN INFLAMMATORYREACTIONS
J R BRADLEY
oepartment ol Medicine. Addenbrodte's Hospbl. Cambrdge c82 200
Vascular endolhelil cells (EC) respond to products d adwaled leucocytes by
undwgoinga rmmber ol l u n c l i l Changes *h
endow them m(h the CapacllY lo
pomote inllammatory r e a e l i . For example. cytokines such as TNF. IL-1 and
interterons cause cytoskelecalchanges which increase vascular permeability. and
the synthesis and eapreslon ol surlace glycoproteim which enable EC to interact
wilh leukocytes. I have lound that sub-injurious concentrations of hydrogen
peroxlde cause reversible EC relraclin and selectively increase steady state
mRNA
and surface e m i o n . ol i n t d l u l a r adhesm molecule-1 (ICAM-1)
and MHC class 1. This abiliy d hydrogen peroxide to mimic some eltects 01
cytokiner rakes lhe possWii that c y l o k i i gene induction may be medlaled by a
lree-cadical dependent pathway. In suppoll d this TNF and 1L-l-induclw)nof the
Iramcriplbn lactor NFKB. of mRNA encoding endothelil leucocyle adhesion
nukuIe-1 (ELAM-1). ICAM-1 and vascular cell adheson molecule-1 (VCAM-1).and
ol sutace ercpressbn d there molecules. can be in part inhailed by the antioxidant Kace(yl-L-cysteine. m e r . hydrogen peroxide does mt aclvale NFrB
in EC. Furthemnre.co-trealm ol EC with hydrogen peroxideihbils TNFinduced
oene expression at 4h. an Meet which is associsted with reversible inhaiton ol
spaatk Iialj-TNF binding lo EC sutlace receptors These results suggast that
hydmgen pem& c a n acIhrale vascular endolhelium. but that the elfects. and the
s i g n a l i mechanisms imohred. dilter lrom those d cytokines I have investigated
lutther the signalling pathways involved in cytokine aclivation 01 EC Binding 01
cylokine to EC sullace receplors is IoUowed by lnternalisatlon of the receptorcyldrine conplex. Ihave found that expasure d &I$ to phamawbglcalinhibnm ,
d reeepla-medialed endocytoda such as hypertonicly. cytoplasm acdlicalion.
metabolic lnhbnbn by phenylarsine oxide. and primary amines. each inhibits
intemalitbn ol TNF. and each inhibiis TNF-inducedsurface expressm 01 ELAM1. Remarkably. aU lrealmenls exeepl phenyiarsineox&. which irreversw inhiMs
EC prolein synthesis. selectively inhibii the response to TNF compared to the
.
response 10 PMA. a d w that Induces EUM-1 through a pathway that bvpasss
surface receptors Primary amnes. Whtch can be used lor up In 72h under
physlokgcat culture conditions. inhibit TNF induction 01 C A M 1 and VCAM t
expresston. as well as IL-1-inducedincreases in ELAMI CAM-I and VCAM-1
Primary annnes ako inhbt TNF-. IFN+ and IFN-~ned~aled
induction d class I
MHC molecules and IFN7-md1atedinducton d class II MHC molecules Levels 01
mRNA encoding cylokine-inducible molecules are also selectively reduced by
primary amines These results suggest that gene induction by inflammatory
cytokines may involve receptor-mediated endocylosis Colleclively these data
suggest that anli-oxidanls and primary amnes may provlde two polenlially rloucl
therapies Whch d l l y the intlammalory capaclty ot EC
13 IDENTIFICATION OF TRANSCRIPTION FACTORS
INVOLVED IN HUMAN CARDIAC GENE EXPRESSION
N BRAND, P BHAVSAR, N EABHADE, M YACOUB and P
BARTON
Molecular Biology Group, Department of Cardiothoracic
Surgery, National Heart and Lung Institute. London SW3 6LY,
UK
We are studying how cardiac gene expression may be regulated
in two ways; by dissecting at the molecular level the promoter
for the human cardiac Troponin I gene (TnIc), expressed solely
in cardiac muscle and cloned in our laboratory (Vallins er al
(1990) FEBS Letts m:57-61; Barton ef 01, in press), and by
cloning transcription factors (TFs) from cardiac muscle and
analysing their function.
Using reverse transcriptaselpolymerasechain reaction
techniques (RTlPCR) we have isolated cDNA clones for six
potential TFs expressed in human heart which are related in
sequence to the mammalian testis-determining factor
These facton, named SOX for =-box.
are expressed in both
adult atrial and ventricular muscle, and also fetal heart (Denny
ef al(1992) NAR a:2887). We are currently charactensing
one clone, SOXS. which appears to be expressed only in
muscle, including cardiac, skeletal and vascular smooth
muscles. Further, using RTlPCR we have been unable to
identify from cardiac muscle facton which are analogous to the
MyoD family of TFs expressed in skeletal muscle.
A n atrial muscle cDNA library was screened w i t h
oligonucleotide probes specific for conserved regions within
zinc finger TFs. Several cDNA sequences related to the
Drosophila gap gene kruppel were isolated. including an Spllike sequence and at least two sequences which may represent
alternatively spliced products of the gene encoding the human
homologue of the mouse gene mkr5. Additionally we have
cloned a novel kruppel-related cDNA called PLZF (for
. RomyelocyticLeukaemia Zinc Anger) in collaboration with Dr.
Arthur Zelent, Leukaemia Research Fund Centre, London.
-PLZF was initially identified from a single case of acute
promyelocytic leukaemia in which a t(1 I ; 17) translocation
involving the PLZF and relinoic acid receptor-a loci results in
the expression of novel reciprocal transcripts encoding
chimaeric TFs (Chen er ul, EMBO 1.. in press). The function
of PLZF in cardiac muscle is currently being examined.
m.
'
14 , THE ROLE OF THE EXTRA-CELLULAR MATRIX IN THE
MIGRATION AND LOCALISATION OF THE HAIRY CELLS
(HCs) OF HAIRY-CELL LEUKAEMIA (HCL)
].BURTHEM P.K.BAKER J.C.CAWLEY
Department of Haanatology. Royal Livapool University Hospital.
Prescot Street. Liverpool L7 8XP. England.
t
The tissue distribution of the malignant HCs in HCL is very distinctive
and includes invasion of splenic red pulp, hepatic sinusoids and bone