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Volume 35 / No. 2 / 2001
Alexander Kiss, Dana Jurkovicova, Daniela Jezova, Olga Krizanova
Institute of Experimental Endocrinology and
Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, 833
06 Bratislava, Slovakia
E-mail: ueenkiss@savba.savba.sk
Objective. To study functional interactions between angiotensin II AT1
receptors and nitric oxide (NO) activity in different brain areas in rats
exposed to immobilization stress.
Methods. Central inhibition of nitric oxide synthase (NOS) was provided
by intracerebroventricular (i.c.v.) administration of
(N-omega-nitro-L-arginine-methylester) L-NAME and analysis of AT1
receptor mRNA was performed using semiquantitative reverse
transcription-polymerase chain reaction (RT-PCR) technique. The immobilization
in prone position lasted 2 hrs and the rats were sacrificed 24 hr later. The
hypothalamus, hippocampus, thalamus, and cortex were isolated from fresh brains.
Results. In the cortex, gene expression of AT1 receptors was
unaffected either by L-NAME treatment, or by a single exposure to
immobilization stress for 2 hours followed by 24 hours of rest. In the
hippocampus, the repeated treatment with L-NAME increased mRNA levels of AT1
receptors approximately 9-times compared to those in the control (untreated)
group. Immobilization also increased AT1 receptor mRNA levels in the
hippocampus which was similar to that induced by the L-NAME.The increase of AT1
receptor mRNA levels in the hippocampus of immobilized rats was not further
altered when the animals were pretreated with L-NAME. In control rats, exposure
to immobilization resulted in a significant rise in mRNA levels coding for
AT1 receptors in the hypothalamus, but not in the thalamus. L-NAME
treatment showed a tendency of increase in AT1 receptor mRNA
levels in the hypothalamus. Moreover, when animals treated with L-NAME were
subjected to immobilization, a further increase in AT1 receptor
mRNA levels was observed in the hypothalamus in comparison with corresponding
controls.
Conclusions. The present data indicate that a single immobilization
stress results in increased gene expression of AT1 receptors in the
hypothalamus and hippocampus. The rise in AT1 mRNA levels in the same
brain structures after repeated treatment with L-NAME allow to suggest an
interaction between the central angiotensin II and nitric oxide.
Key words: Nitric oxide synthase – AT1 receptors – Gene
expresssion – Hypothalamus – Hippocampus –Immobilization stress – Rat
ENDOCRINE REGULATIONS, Vol. 35, 65–70, 2001
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Ferit Taneri, Aylar Poyraz, Buelent Salman, Ercuement Tekin, Nalan Akyuerek, Orhan Bayram, Erhan Onuk
Departments of General Surgery and Pathology,
Gazi University Medical School, Ankara, Turkey
E-mail: bsalman97@hotmail.com
Objective. To compare the diagnosis of thyroid pathological findings by
using frozen section and preoperative imprint.
Methods. From January 1998 to December 1999, one hundred and three
consecutive patients admitted to Department of Surgery, Gazi University Medical
Faculty for thyroid operation, were prospectively included into the study. In
all patients, imprint and frozen section were carried out from their suspected
nodules and the results were compared with the permenant biopsy. Those findings
used to find out sensitivity, specificity, negative predictive value (NPV) and
positive predictive value (PPV) of frozen section and imprint. Because of the
definitve differentiation of malignant or benign lesions could not be done,
three patient were excluded from the study.
Results. In our study; sensitivity, specificity, PPV, NPV and accuracy
for imprints was found as 83.3%, 97.7%, 83.3%, 97.7% and 96% (respectively),
while respective corresponding data for frozen section were 81.8%, 96.6%, 75%,
97.7% and 95%. In one patient, the pathologcal finding of follicular carcinoma
as found by permanent section was accurately diagnosed by imprint, but missed by
frozen section. Both the imprint and frozen section failed to diagnose two
papillary carcinoma. Overall cancer rate among 103 patients was 12 % (nine
papillary carcinoma, one Hürthle cell carcinoma and two follicular carcinoma).
Conclusion. Both the frozen sections and imprints showed high sesitivity
rate and similar accuracy rates. So, if there is no opportunity for frozen
section, the imprints could be used. Furthermore, the use of imprints is less
time consuming and less expensive than that of frozen sections.
Key Words: Thyroid surgery – imprint cytology – frozen sections –
diagnostic validity
ENDOCRINE REGULATIONS, Vol. 35, 71–74, 2001
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Anna Janecka, Maria Zubrzycka
Department of General Chemistry and
Department of Experimental and Clinical Physiology, Institute of Physiology and
Biochemistry, Medical University of Lodz, 90-131 Lodz, Poland
E-mail: ajanecka@csk.am.lodz.pl
Objective; Structure-activity relationship studies of a series of
new heptapeptide analogs of somatostatin with C-terminal modifications were
performed.
Methods; New somatostatin analogs were synthesized by solid-phase method.
The suppression of the release of growth hormone by the new analogs was assayed in
vivo in rats, and the duration of action was investigated using growth
hormone time-course assay. Growth hormone concentration in plasma samples was
determined by RIA.
Results; The growth hormone release inhibitory activity of the new
analogs was up to 50 times greater than that of somatostatin. Hydrophilic
substitutions at the C-terminus seemed to be advantageous for potency. The most
potent analog of the series, D-Phe-c[Cys-Phe-D-Trp-Lys-Thr-Cys]-NH-CH2-CH2-OH
showed the most prolonged activity by inhibiting the release of growth hormone
for at least 3 h. The analogs containing D-Phe or D-Tyr at the N-terminus were
almost equipotent, which proves that the exocyclic N-terminal residue is not
involved directly in the receptor recognition.
Conclusions; New heptapeptide analogs of somatostatin with C-terminal
modifications were more potent and longer acting than the native hormone.
Key words: Somatostatin analogs – Solid phase peptide synthesis –
Structure-activity relationships
ENDOCRINE REGULATIONS, Vol. 35, 75–79, 2001
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Angelina Russinova, Milena Mourdjeva, Stanimir Kyurkchiev, Ivan Kehayov
Institute of Experimental Morphology and Anthropology and
Institute of Biology and Immunology of Reproduction, Bulgarian Academy of
Sciences, 1113 Sofia, Bulgaria
E-mail: russinova@dir.bg
Objective. Atrial natriuretic factor (ANF) and its receptors were
identified in various tissues and organs including the female reproductive
system. The present studies were undertaken to investigate ANF localization in
immature rat ovaries, and the changes of ANF expression in response to different
ovarian hormonal conditions.
Methods. ANF was characterized immunocytochemically during different
ovarian status using an animal model with synchronized ovarian follicular growth
and atresia induced by pregnant mare serum gonadotropin (PMSG). This treatment
in prepubescent rats produces a series of ovarian changes mimicking
follicular growth and differentiation (48 h after PMSG treatment) and
atresia (96 h after PMSG treatment) and permits the synchronization of
events for investigation purposes.
Results. Our findings showed that in immature rat ovaries ANF was
localized primarily in granulosa cells of all developing follicles (healthy and
atretic). Immunocytochemical analysis revealed that during follicular growth and
differentiation (48 h after PMSG) ANF was present in all steroid producing
cells – interstitial, thecal and granulosa cells. ANF immunoreactivity was
also detected in the cytoplasm and nuclear compartment of the growing oocytes.
In all atretic follicles ANF staining was detected at 96 h after PMSG
injection, but the intensity of the reaction varied with the degree of atresia,
the mostly pronounced reaction being observed in the late stage of atresia.
Conclusions. These results indicate that ANF represents a unique
peptide, which is expressed in different ovarian cell types and responds to
different developmental programming.
Key words: Atrial natriuretic factor – Immunocytochemistry – Ovary
– Follicular development – Rat
ENDOCRINE REGULATIONS, Vol. 35, 81–89, 2001
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Christian A. Koch, Karel Pacak
Pediatric and Reproductive Endocrinology Branch, National Institute of Child
Health and Human Development, National Institutes of Health, Bethesda, MD 20892,
U.S.A.
E-mail: kochc@exchange.nih.gov
We here report a 32-year old homosexuell man with AIDS who had an
abnormal ACTH stimulation test while taking megestrol actetate (megace). On
further evaluation, he was found to have recurrent Non-Hodgkin lymphoma (spleen)
and intracranial toxoplasmosis, perhaps imitating or aggravating symptoms
suggestive of adrenal insufficiency (AI). We diagnosed secondary AI due to
megace treatment and tapered this medication under simultaneous hydrocortisone
replacement therapy. After the patient’s intracranial toxoplasmosis had been
treated with intravenous bactrim, his symptoms disappeared. We conclude that
patients with AIDS on megace therapy should receive special attention in regards
to the potential development of AI, especially in stress situations such as
infections or pain.
Key words: Megestrol acetate – HIV – ACTH – Adrenal insufficiency
– Toxoplasmosis – Stress
ENDOCRINE REGULATIONS, Vol. 35, 91–93, 2001
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Salvatore Alesci, Christian A. Koch, Stefan R. Bornstein, Karel Pacak
Pediatric & Reproductive Endocrinology Branch , National Institute of
Child Health and Human Development, National Institutes of Health , Bethesda ,
MD (USA);
Institute of Endocrinology, Prague, Czech Republic
E-mail : alescis@mail.nih.gov
Adrenal androgens (AA) are mainly produced by the human adrenal cortex. ACTH
is the major regulator of their secretion. However, other factors, such as
gonadal sex steroids, insulin, growth hormone, prolactin, hypothalamic peptides
and growth factors have been involved in AA regulation. More recently, it has
become well accepted that, besides systemic factors, AA secretion is under the
control of the ”sympathoadrenal system” and ”immunoadrenal system”. Here
we review the extraadrenal and intraadrenal mechanisms of AA regulation and how
they may relate to endocrinoimmunosenescence.
Key words : DHEA – Adrenal androgens – Adrenopause – Aging
–ACTH– Minireview
ENDOCRINE REGULATIONS, Vol. 35, 95–100, 2001
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Ladislav Macho, Richard Kvetnansky, Maria Fickova, Irina A. Popova., Anatolij Grigoriev
Institute of Experimental Endocrinology, Slovak Academy of Sciences, 833
06Bratislava, Slovakia
State Scientific Center, Institute of Biomedical Problems, Russian Academy of
Sciences, Moscow, Russia
This minireview summarizes the results of the observations on changes in
endocrine functions of rats exposed to space flights for various periods. The
results found after space flights are compared with those obtained from rats in
acute or repeated restrain stress. A slight increase of plasma
catecholamine levels was observed in rats after space flight of longer duration
(>14 days), but no changes in catecholamine content in the activity of
catecholamine synthesizing enzymes were noted in adrenal medulla and in
hypothalamus. The norepinephrine content was, however, decreased in several
nuclei selected from hypothalamus of flight rats. Plasma corticosterone levels
were increased after space flight and morphological examination of pituitary
showed elevated activity of corticotrophs. However, the plasma levels of ACTH
were not increased in rats 6 hours after space flight. These changes in plasma
hormone levels affected the activity of enzymes involved in metabolism of amino
acids in liver and lipolysis in adipose tissue. The plasma levels of
testosterone and triiodothyronine were diminished after space flight suggesting
the suppression of the thyroid and gonadal activity. Increase of plasma insulin
and glucose levels were found in rats after space flight, but the glucagon
values were not changed. Comparing these results from flight rats with the
animals exposed to acute or repeated stress indicate that long stay in
microgravity do not represent very intensive stressogenic stimulus for
adrenocortical and sympatho-adrenomedullar systems, and hormone alterations
observed after space flight may be due to acute gravitational stress resulting
from a return to Earth gravity. Therefore further studies including the
inflight animal experiments on a board of International Space Station are
necessary for elucidation of the effects of microgravity on endocrine functions.
Key words: Space flights – Rats – Adrenal glands – Thyroid function
– Sympatho-adrenomedullary system – Gonads.
ENDOCRINE REGULATIONS, Vol. 35, 101–114, 2001
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ASSISTED FERTILIZATION AND NUCLEAR TRANSFER IN MAMMALS
Edited By Don P. Wolf, Mary Zelinski-Wooten (Oregon Regional Primate Research Center, Beaverton, OR); Humana Press , Totowa, New Jersey, 2001, 305 pages, hard cover, US $ 145.00; E-mail : humana@humanapr.com
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Koch C.a., Vortmeyer A.o., Huang S.c., Alesci S., Zhuang Z., Pacak K. (Bethesda, MD, USA) Genetic aspects of phaeochromocytoma. Endocrine Regul 35, 43-52, 2001
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