15038 studies
We used three putative vasoactive intestinal peptide (VIP) antagonists: 1) [4C1-D-Phe6,Leu17]VIP, 2) [N-Ac-Tyr1,D-Phe2] GRF(1-29)-NH2, and 3) VIP(10-28) to assess the involvement of endogenous VIP in the regulation of thyroid hormone secretion and th…
African Green monkeys were injected (2 x daily subcutaneously for six months) with human GRF(1-44)-NH2 (10 micrograms/kg BW) or a more potent analog, [desNH2Tyr1,Ala15]-hGRF(1-29)-NH2 (2 micrograms/kg BW) to determine the potential of each peptide to…
Vasoactive intestinal peptide (VIP) receptors coupled to activation of adenylate cyclase have been previously identified in seminal vesicle membranes of rat. In the present study we demonstrate that the synthetic peptides [4-Cl-D-Phe6,Leu17]VIP and t…
Immature rats display a blunted rise in urinary phosphate but not adenosine 3',5'-cyclic monophosphate (cAMP) excretion in response to parathyroid hormone (PTH), perhaps as a consequence of the increased demand for phosphate during growth. Because a…
1. The effects of vasoactive intestinal polypeptide (VIP) antagonists [AC-Tyr1, D-Phe2]-GRF(1-29)-NH2 and [4-Cl-D-Phe6, Leu17]-VIP on excitatory neuroeffector transmission in the dog and cat trachea were investigated by use of microelectrode, double…
1. The perfused adrenal gland of the rat was used to establish the identity of a non-cholinergic substance involved in splanchnic nerve-mediated secretion of catecholamines. 2. The perfused adrenal medulla was rich in vasoactive intestinal polypeptid…
Angus and Charolais heifers (195 +/- 7 kg) were actively immunized against growth hormone-releasing factor (GRF) to evaluate the effect on concentrations of somatotropin (ST), insulin-like growth factor I (IGF-I), insulin (INS), growth, and onset of…
This paper reports our attempt at designing new immunostimulating peptides which are chemically related to the bioactive peptides thymosin alpha 1 and thymopentin. Three peptides were synthesized, Asp-Leu-Lys-Glu-Arg-Lys-Asp-Val-Tyr (3), Arg-Lys-Asp-…
A combination treatment with thymosin alpha 1 (200 micrograms/kg) for 4 days, followed by a single injection of murine interferon alpha/beta (3 x 10(4) international units/mouse). starting 2 days after cyclophosphamide treatment (200 mg/kg, single in…
Using immunohistochemical methods, we have investigated the cellular distribution of prothymosin alpha (ProT) in adult rat testis. A policlonal antibody raised against thymosin alpha 1 conjugated to keyhole limpet hemocyanin was used. ProT immunoreac…
In this report we demonstrate that thymosin alpha 1 (T alpha 1), a synthetic peptide composed of 28 amino acid residues, and thymosin fraction 5 (TF5) enhance the number of high affinity interleukin 2 receptors (IL-2R) expressed by human peripheral b…
A thymic epithelial cell (TEC) line (B/c. TEC-L1) was established from a normal thymus of a 4-week BALB/c mouse. The B/c. TEC-L1 had an epithelial morphology showing a contact-inhibited cobblestone-like arrangement with occasional desmosome-like stru…
Different hormones (thymulin, thymosin alpha 1, vasopressin), antigenic markers of cortical and subcapsular/medullary thymic areas and tumour associated antigens were studied on paraffin or frozen section and cultures of human epithelial thymic tumou…
Long-term treatment with recombinant interleukin-2 (IL-2) of diabetes-prone BB rats had contrasting effects in two different BB rat sublines. Diabetes development was enhanced in the subline with a low intrinsic diabetes risk and suppressed in the su…
Thymosin alpha 1 (T alpha 1), the N-terminal 28-amino acid fragment of prothymosin alpha (ProT alpha), and ProT alpha, although originally isolated from whole thymus extracts, are also present in nonthymic cells and tissues. We used an ELISA with an…
Prostaglandins of the E series have been implicated as possible mediators of thymosin alpha 1 (TA-1) effect on mitogen stimulated lymphoproliferation. In the present study human peripheral blood mononuclear cells were stimulated with concanavalin A i…
Thymic hormonal factors were isolated from mouse thymus by two methods. (1) Thymic cytosols in phosphate buffer saline were filtered through Sephadex G100 with 0.1 M NH4HCO3 (pH 8.0) as buffer and the protein peaks were collected. (2) Protein having…
The hepatic receptor for VIP was solubilized from rat liver plasma membranes with 1.4% digitonin and shown to conserve its ability to bind to the ligand. This solubilized receptor demonstrated the high affinity and specificity for VIP (KD approximate…
The effect of thymosin fraction 5 and its synthetic component thymosin-alpha 1 administered i. p. and i. c. v. on the behavior of 219 Wistar rats in the open field was studied to establish the effective dose and time of action of both substances. It…