Læknablaðið - 15.01.1998, Page 44

42
LÆKNABLAÐIÐ 1998; 84
Nýr doktor í læknisfræði
Þann 20. september 1996 lauk Þóra Stein-
grímsdóttir doktorsprófi í læknisfræði frá Upp-
salaháskóla. Doktorsritgerðin ber enska titil-
inn Energy Economy of the Human Uterus. In
vitro and in vivo Investigations of the Uterine
Smooth Muscle in Different Functional States
og fjallar um orkubúskap legvöðva. Ágrip úr
ritgerðinni fer hér á eftir.
This thesis concerns some aspects of energy
metabolism of the human uterus in term preg-
nant and the nonpregnant state. The uterine
smooth muscle was compared with striated
skeletal muscle in the same individual. Uterine
uptake and release of some energy-related me-
tabolites (amino acids and metabolites of car-
bohydrates, fat and nucleotides) were estimat-
ed by means of calculation of arteriovenous
differences in their concentrations across the
term pregnant uterus before onset of labour.
Concentrations of the same metabolites as well
as some nucleosides and high-energy phospho-
compounds were also determined in lyophil-
ized biopsies of the myometrium and the striat-
ed rectus muscle obtained in term pregnancy
before onset of labour. Uterine smooth muscle
and the striated gastrocnemius muscle of non-
pregnant women of reproductive age were in-
vestigated in vivo by phosphorus magnetic re-
sonance spectroscopy (31P-MRS) with regard
to the content of high-energy phosphocom-
pounds and their interrelationships.
The arteriovenous differences across the
term pregnant uterus were positive (denoting a
uterine uptake) only for glucose. For all other
metabolites the differences were negative (am-
ino acids, lactate, free fatty acids and glycerol)
or nonsignificant (pyruvate, hypoxanthine,
xanthine and urate).
The term pregnant myometrium contained
Þóra starfar sem sérfræðingur í kvenlækningum við Há-
skólasjúkrahúsiö í Uppsölum. Heimilisfangið þar er;
Kvinnokliniken, Akademiska sjukhuset, S-751 85 Uppsala,
Sverige.
about twice as much glucose and lactate as did
the rectus muscle. There was also a striking
myometrial abundance of the nucleosides,
adenosine, inosine and uridine. The concent-
rations of phosphocreatine (PCr) and ATP
were lower in the uterine than in the striated
muscle. The PCr/ATP ratio in the myometr-
ium had a value of about one third of the value
in the rectus muscle.
31P-MRS in vivo revealed a three times hig-
her PCr/ATP ratio in the striated muscle than
in the uterine smooth muscle, thus confirming
the difference between the ratios in the
biochemically analyzed biopsies in vitro.
The term pregnant uterus utilizes glucose as
its principal and sole energy substrate. The
anaerobic component of glucose oxidation is
predominant in the uterine muscle. Augment-
ed glycogen turnover in the myometrium is
indicated. From these studies, it can be conclu-
ded, that the uterine smooth rnuscle appears as
an organ with highly restrictive energy dem-
ands.