Földes J

Endothelin concentrations are elevated in plasma of patients with primary and secondary hyperparathyroidism

Endothelin Concentrations are Elevated in Plasma of Patients with Primary and Secondary Hyperparathyroidism P. Lakatos, A. Tátrai, 1 J. Földes, C. Horváth, J. Makó, P. H. Stern 1st Department of Medicine, Semmelweis University Medical School, Kora ́nyi 2/a, Budapest, H-1083, Hungary Department of Molecular Pharmacology and Biological Chemistry, Northwestern University Medical School, 303 E. Chicago Ave., Chicago, IL 60611, USA

Human tolerability studies with D-Met2, Pro5-enkephalinamide

As reported previously D-Met2,Pro5-enkephalinamide (EA) is a highly active enkephalin analogue. To examine its human tolerability male volunteers were treated s.c. with increasing doses (0.1-30.0 mg). The observed autonomic effects were as follows: feeling of heaviness in the limbs, dry mouth, pallor of the face and conjunctival injection. There was no significant change in blood pressure, pulse and respiratory frequency. The autonomic effects appeared within 15-30 min. However, its effects on mood and wakefulness i.e. slight drowsiness, decrease in psychic tension and emotional detachment developed only later. The serum prolactin level increased dose-dependently, while the growth hormone (HGH) content showed biphasic dose-response pattern. The TSH content increased only at the highest doses applied (10.0-30.0 mg).

Effects of methysergide, bromocriptine and naloxone on prolactin, growth hormone and TSH release induced by d-Met2,Pro5-enkephalinamide in man

Abstractd-Met2,Pro5-enkephalinamide (EA) 10 mg, given SC, induced a dramatic rise in serum prolactin (PRL) and growth hormone (GH) levels in healthy male volunteers. The TSH content was also moderately elevated. Naloxone 0.8 mg administered IV abolished these effects. Bromocriptine 2.5 mg given per os also antagonized EA-induced PRL and TSH release but potentiated the GH surge. Methysergide 2.0 mg administered orally partially reversed EA-elicited PRL release, further augmented GH liberation and did not modify TSH output. The data indicate that inhibition of the dopaminergic tone and/or activation of certain serotonergic mechanisms play an important role in the EA-induced release of PRL and TSH. However, primarily other neurotransmitters might mediate the GH liberation elicited by this opioid peptide.

Subclinical hypothyroidism and the risk for cardiovascular diseases. Are epidemiological studies giving the right answers

There is ongoing debate whether subclinical hypothyroidism may exert deleterious effects on the cardiovascular system with the consequences of increased morbidity and mortality. To elucidate this problem many epidemiological studies have been performed, however, these studies have not given an unambiguous answer so far. Many confounding elements are influencing the evaluation of these investigations which must be taken into consideration. Authors argue for the use of age specific reference limits for TSH (especially in older age, where TSH level is often shifted to a higher level) to avoid significant misclassification of patients with abnormal TSH who may or may not have thyroid dysfunction. Furthermore, recent studies have shown that subclinical hypothyroidism is associated with increased ischemic heart disease risk, mainly in individuals under the age of 65 years. In the future, well designed prospective randomized studies with age stratified groups and vascular events as the primary endpoint are required and it is anticipated that these studies will give the proper answer whether early substitution therapy with thyroxin will be able to reverse the ischemic heart disease risk in affected patients.