Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A case of pseudohypoparathyroidism has been investigated. Indirect evidence allows to eliminate a defect of renal 1 alpha-hydroxylase as the determining factor of this condition. Similarly, the increased size of the mean surface area of the cross-section of periosteocytic lacunae, as determined on decalcified sections of bone obtained by transiliac biopsy, shows the osteocytes to be sensitive to the endogenous PTH, discarding cAMP response to PTH in bone as a prerequisite for PTH action on bone. The authors conclude from these data and from previous experiments that the defect of parathyroid function in this condition probably relates to the existence of an abnormal PTH molecule and/or metabolism and/or interaction with the receptors sites. The endocrine function was studied as well. Prediabetes was demonstrated, as well as primary latent hypothyroidism (TRH test). Prolactin release could not be stimulated by TRH, levodopa, metoclopramide, chlorpromazine and insulin hypoglycemia. The latter produced a normal release of ACTH (as ascertained by plasma cortisol levels) and GH, and possibly a sluggish response of glucagon and gastrin. There was a deficiency of urinary concentration upon restriction of fluid intake. This was only partially corrected by ADH administration.
 ...
PMID:[Physio-pathology of pseudohypoparathyroidism (author's transl)]. 22 97

In this study we analyzed the ontogeny and location of gastric TRH in human fetuses, preterm and term newborns, and adults. TRH immunoreactive cells were found in the antrum towards the bottom of developing glands and double immunostaining demonstrated that this neuropeptide is coexpressed with gastrin in the same cell (G-cell). In the youngest fetuses studied (12 weeks) G cells were few and contained both gastrin and TRH. They increased in number during development and were most abundant between 26 and 36 weeks of gestation. These morphological data correlated with total immunoreactive TRH content extracted from the whole stomachs of six fetuses and two preterm infants. On the contrary G cells containing both hormones were decreased in the newborn at term and not identified in the adult whereas those containing only gastrin were numerous in both. The TRH extracted was indistinguishable from synthetic TRH using chromatographic, radioimmunologic, and enzymatic criteria. As has already been reported, TRH was found in insulin-containing cells of the islets of Langerhans in the pancreas of our fetuses and newborns. These cells presented a similar development pattern to the gastric G cells.
 ...
PMID:Gastrin (G) cells are the cellular site of the gastric thyrotropin-releasing hormone in human fetuses and newborns. A chromatographic, radioimmunological, and immunocytochemical study. 159 90

The role of gastrin, acetylcholine and histamine in the acid response to central vagal activation induced by intracisternal injection of the stable analog, RX 77368, was further investigated in urethane-anesthetized rats with gastric fistula. The gastrin monoclonal antibody 28-2 injected intravenously, at a dose previously shown to prevent gastrin-induced stimulation of acid secretion, did not alter the peak acid response to intracisternal injection of RX 77368 (15 ng). The TRH analog (30 ng) injected into the cisterna magna increased levels of histamine measured in the hepatic portal blood. Cimetidine administered at a dose which completely blocked the stimulation of gastric acid secretion produced by intravenous infusion of histamine, inhibited by 62% the stimulatory effect of intracisternal RX 77368 (30 ng). The M1 muscarinic antagonist, pirenzepine, completely prevented the acid secretion induced by intracisternal RX 77368 (30 ng). These results indicate that the acid response to central vagal activation by the TRH analog in rats involved M1 muscarinic receptors along with histamine release acting on H2 histaminergic receptors whereas gastrin does not appear to play an important role.
 ...
PMID:Role of acetylcholine, histamine and gastrin in the acid response to intracisternal injection of TRH analog, RX 77368, in the rat. 210 37

During the last years, several important advancements have been made that are of importance for our understanding of the distribution and localization of neurons and cells producing TRH-LI. As detailed in other chapters in this volume, the precursor for TRH has been characterized that has allowed production of antibodies raised against specific sequences of this precursor. This, in turn, has provided new tools for the immunohistochemical elucidation of TRH systems in the CNS. The TRH precursor has also been cloned, leading to possibilities for studying the localization of TRH mRNA with in situ hybridization. Finally, as shown in this paper, improvement of the fixation technique has made it possible to visualize extensive TRH-immunoreactive cell body and fiber systems with antiserum raised against the TRH tripeptide. The results from the latter studies and those with antisera directed to the TRH precursor and in situ hybridization are in good agreement, with some minor exceptions. It should be pointed out that some of the systems described here, for example TRH positive-cell bodies in cortical areas and the hippocampal formation, contain only a very weak immunoreactivity. As always with immunohistochemical techniques, the possibility of crossreactivity with TRH-like peptides or TRH-like sequences within larger proteins must be considered. The present results confirm the presence of TRH-LI in the insulin-producing beta cells of the pancreas, which with the improved technique can be demonstrated also in early adulthood in rats and guinea pigs. Moreover, it could be established that TRH-LI is present in neurons in the gastrointestinal tract as well as in a population of endocrine cells in the antrum of the stomach of the guinea pig. These cells seem at least partly to be identical to the well-known gastrin-producing cells. TRH-LI has been observed to occur in neurons already containing a classical transmitter and/or other peptides. Of particular importance here seems to be a descending bulbospinal system that in addition to TRH co-contains 5-HT, substance P-LI, galanin-LI, human growth hormone immunoreactive material, and proctolin-like material. The significance of this coexistence is not well understood, but interesting interactions have been observed. Attempts to manipulate the TRH phenotype in these medullary neurons by transplantation to other sites in the brain has so far shown that the expression of this peptide seems fairly stable.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Distribution of TRH-like immunoreactivity with special reference to coexistence with other neuroactive compounds. 249 89

Qualitative and quantitative expression of m.RNA coding for Peptidyl-Glycine alpha-Amidating Monooxygenase (PAM) in the developing rat pancreas was investigated by Northern and dot blot hybridization, with a bovine PAM c.DNA probe (0.7 kb fragment). A specific hybridization signal was evidenced for a 3.7 kb m.RNA species. Measurement of PAM m. RNA rate during the rat pancreas ontogenesis revealed a biphasic profile which appeared corelated with that of gastrin and TRH m.RNA respectively. On the other hand, streptozotocin-treatment resulted in a 50% decrease of PAM m.RNA levels.
 ...
PMID:Ontogenetic expression of peptidyl-glycine alpha-amidating monooxygenase mRNA in the rat pancreas. 252 48

Multiple endocrine neoplastic diseases are genetically determined conditions with particular organ patterns for endocrine tumors. In Type I or Wermer's syndrome the endocrine pancreas, anterior pituitary and parathyroids are involved, insulinoma being the most frequent pancreatic tumor. To facilitate diagnosis, a prolonged oral glucose tolerance test, a fasting test and determination of the glucose-insulin ratio are recommended. Localisation is sought by computer tomography and angiography. A gastrinoma is excluded on the basis of normal gastrin levels in serum and by means of the secretin-provocation-test. Pituitary tumors can be classified more closely with prolactin levels and releasing-hormone tests (LH-RH and TRH). Prolactinoma is the most frequent pituitary tumor and amenable to bromocryptin treatment. If Wermer's syndrome is suspected, primary hyperparathyroidism has to be excluded on the basis of calcium and parathormone levels. Chief cell hyperplasia or multiple adenomas are frequent. Surgical resection is necessary.
 ...
PMID:[Type I multiple endocrine neoplasia--Wermer syndrome]. 257 44

Specific somatostatin (SRIH) receptors on human pituitary adenoma cell membranes were characterized using [125I]Tyr11-SRIH as the radioligand. Specific binding of [125I] Tyr11-SRIH to adenoma cell membranes reached a steady state within 30 min at 25 C, and semilogarithmic analysis of the data revealed that the rate of the binding was linear at 25 C with a t1/2 of 13.2 min. Specific binding increased linearly with 5-160 micrograms plasma membrane protein. SRIH-14 and SRIH-28 inhibited [125I]Tyr11-SRIH binding to adenoma cell membranes with ID50S of 0.32 and 0.50 nM, respectively, while secretin, glucagon, gastrin, cholecystokinin-8, bombesin, TRH, LHRH, human GH-releasing factor-(1-44)-NH2, D-Ala2-met-enkephalin, gamma-aminobutyric acid and taurine did not significantly inhibit binding. All of 13 GH-secreting adenomas investigated had specific and high affinity SRIH receptors, with a dissociation constant (Kd) of 0.80 +/- 0.15 nM (mean +/- SEM) and a maximal binding capacity (Bmax) of 234.2 +/- 86.9 fmol/mg protein (mean +/- SEM). Among five of the nonsecreting pituitary adenomas examined, two had SRIH receptors with Kd values of 0.18 and 0.32 nM and Bmax values of 17.2 and 48.0 fmol/mg protein, respectively. In the remaining three, SRIH receptors were not detected. These results indicate that GH-secreting adenomas as well as some nonfunctioning adenomas have specific SRIH receptors, and hence, the function of the adenomas could be altered by SRIH.
 ...
PMID:Specific somatostatin receptors on human pituitary adenoma cell membranes. 286 81

A tabular synopsis is presented for articles concerned with the effects of peptides on the central nervous system that appeared in the journal Peptides from 1980-1985. A table arranged alphabetically by peptide and one arranged by effects, both listing routes of injection, species, direction of change, and qualifying notes, provides easy cross-referencing of peptides and their effects. Over 80 peptides and over 135 effects are listed. The list of peptides includes, but is not limited to: ACTH, angiotensin, bombesin, bradykinin, calcitonin, casomorphin, CCK, ceruletide, CGRP, CRF, dermorphin, DSIP, dynorphin, endorphins, enkephalins, GRF, gastrin, LHRH, litorin, metkephamid, MIF-l, motilin, MSH, NPY, NT, oxytocin, ranatensin, sauvagine, substances P and K, somatostatin, TRH, VIP, vasopressin, and vasotocin. The list of effects includes, but is not limited to: aggression, alcohol, analgesia, attention, avoidance, behavior, cardiovascular regulation, catalepsy, conditioned behavior, convulsions, dopamine binding and metabolism, discrimination, drinking, EEG, exploration, feeding, fever, gastric secretion, GI motility, grooming, learning, locomotor behavior, mating, memory, neuronal activity, open field, operant behavior, rearing, respiration, satiety, scratching, seizure, sleep, stereotypy, temperature, thermoregulation and tolerance.
 ...
PMID:Central nervous system effects of peptides, 1980-1985: a cross-listing of peptides and their central actions from the first six years of the journal Peptides. 353 8

The neurohumoral pathways mediating intracisternal TRH-induced stimulation of gastric acid secretion were investigated. In urethane-anesthetized rats, with gastric and intrajugular cannulas, TRH or the analog [N-Val2]-TRH (1 microgram) injected intracisternally increased gastric acid output for 90 min. Serum gastrin levels were not elevated significantly. Under these conditions the TRH analog, unlike TRH, was devoid of thyrotropin-releasing activity as measured by serum TSH levels. In pylorus-ligated rats, gastrin values were not modified 2 h after peptide injection whereas gastric acid output was enhanced. TRH (0.1-1 micrograms) stimulated vagal efferent discharge, recorded from a multifiber preparation of the cervical vagus in urethane-anesthetized rats and the response was dose-dependent. The time course of vagal activation was well correlated with the time profile of gastric stimulation measured every 2 min. These results demonstrated that gastric acid secretory stimulation elicited by intracisternal TRH is not related to changes in circulating levels of gastrin or TSH but is mediated by the activation of efferent vagal pathways that stimulated parietal cell secretion.
 ...
PMID:Mechanisms underlying intracisternal TRH-induced stimulation of gastric acid secretion in rats. 393 84

A young woman with acromegaly and Zollinger-Ellison syndrome associated with a GH-releasing factor (GRF)- and gastrin-secreting metastatic islet cell carcinoma was studied by means of specific antisera which recognize various regions of the GRF molecule. Using specific immunohistochemical techniques, the tumor cells were shown to contain GRF, gastrin, and gastrin-releasing peptide, but not GH. During a 4-h period, plasma GRF levels averaged 5.6 +/- 1.4 ng/ml (+/- SD), while GH levels averaged 148 +/- 71 ng/ml. GH secretion was pulsatile and increased after TRH administration. GRF RIAs may be useful in establishing the diagnosis of acromegaly secondary to the ectopic secretion of GRF.
 ...
PMID:Acromegaly and Zollinger-Ellison syndrome secondary to an islet cell tumor: characterization and quantification of plasma and tumor human growth hormone-releasing factor. 609 Apr 97


1 2 3 Next >>