14102 studies
Thymosin beta 4 belongs to a family of ubiquitous peptides present at a high cellular content but still with an unknown intracellular function. The expression of this peptide was studied in concanavalin-A-stimulated, proliferating rat thymocytes duri…
A cloned thymosin beta-10 cDNA and a synthetic oligonucleotide specific for the thymosin beta-4 gene were used to study the in vivo expression of these two genes in the immature rat ovary in response to exogenously administered gonadotropins. Despite…
Thymosin beta 4 (T beta 4), a 43-residue peptide of uncertain function, is widely distributed in most tissues of vertebrates. Southern blot analysis demonstrated that the rat genome contains many closely related T beta 4 sequences. Two distinct T bet…
A competitive enzyme immunoassay using acetylcholinesterase as tracer for thymosin beta 4, has been developed. Using this assay and a previously described EIA for AcSDKP, a negative regulator of pluripotent haematopoietic stem cell proliferation, the…
To evaluate the effects of a gonadotropin-releasing hormone agonist on non-reproductive systems, we administered [D-Leu6,Des-gly10]-GnRH ethylamide (leuprolide; 5 micrograms/day) for 21 days to female Sprague-Dawley rats. In Experiment 1, continuous…
The expression of the actin-sequestering peptide, thymosin beta 4, was analyzed in proliferating rat thymocytes, activated by diverse stimuli, during the early G1 phase and the S phase. In the presence of concanavalin A a 6.3-fold increase of thymosi…
Thymosin beta 10 is one of a small family of proteins closely related in sequence to thymosin beta 4, recently identified as an actin-sequestering protein. A single molecular weight species of thymosin beta 10 mRNA is present in a number of rat tissu…
A peptide preparation of the pineal, epithalamin, when administered chronically, exerts a modulating influence on the diurnal fluctuations of the motoric activity of rats. It also decreases the amplitude of apomorphine stereotypy and induces a restru…
On the pinealectomized rats shifts of main parameters of forced swimming and its time course with increase of rhythmical depression index were observed. Pinealectomy also potentiated depressogenic effect of reserpine which was attenuated by melatonin…
1. A neuroendocrine role for calcitonin (CT) has been suggested by the finding of CT receptors in the hypothalamus. We have recently shown that salmon calcitonin (sCT) inhibits growth hormone releasing hormone (GHRH)-induced GH secretion in man by a…
The possibilities of obtaining polypeptide amides in good yields from polypeptide acids by carboxypeptidase catalyzed transpeptidation have been investigated in different C-terminal amidations catalysed by CPD-Y, placing particular emphasis on the st…
Enzymatic semisyntheses of growth hormone releasing factor (GRF), a 44-residue peptide amide hormone, from C-terminal acid precursors, are compared. A recombinant alpha-amidating enzyme was used to convert the glycine-extended precursor, GRF(1-44)-Gl…
Patients with hyperthyroidism have reduced growth hormone (GH) responses to pharmacological stimuli and reduced spontaneous nocturnal GH secretion. The stimulatory effect of clonidine on GH secretion has been suggested to depend on an enhancement of…
The stability of growth-hormone releasing factor (growth regulating factor; GRF) analogs in porcine plasma was examined. GRF analogs were incubated in porcine plasma at 37 degrees C, extracted and subsequently analyzed using high performance liquid c…
To study the relationship of endogenous GHRH to the changes seen in serum GH concentration in neonatal primates, we administered antiserum to GHRH (GHRH-Ab) or GHRH antagonist, (N-Acetyl-Tyr1,D-Arg2)GHRH-(1-29)-NH2, to unanesthetized, fasted rhesus m…
We have evaluated the effect of pubertal maturation on the GH response to growth hormone releasing hormone (GHRH), pyridostigmine (PD) and the combined administration of PD + GHRH in a group of short normal children. Fifteen were prepubertal (13 boys…
The purpose of this study was to characterize the biological activity of the synthetic rat growth hormone releasing factor analogue rGRF(1-29)NH2 and to compare its action on growth hormone (GH) release to that of authentic rGRF(1-43)OH. We first com…
The applicability of serine carboxypeptidase catalysed transpeptidation reactions, using amino acid amides as nucleophiles, for C-terminal amidation of peptides has been investigated. With the aim of converting an unamidated precursor into GRF(1-29)-…